CN1016852B - Method and device of continuous casting of crystal strip stock - Google Patents

Abstract

The present invention provides a method of continuously casting crystal strip stocks, which is characterized in that molten metal is directly cast into a casting surface (20) in a running state from the outlet end (26) of a casting container to form continuous crystal metal strip stocks. The surface tension of the molten metal which flows out from the outlet end (26) forms the upper surface, the side edges and the bottom of the strip stocks (15); thereby, the strip stocks with favorable surface quality and favorable edges and structures can be obtained. The present invention also provides a device which is provided with a casting container (18), wherein the casting container (18) is provided with a molten metal receiving end (22) and an outlet end (26). Uniform molten metal streams which are fully extended from the outlet end (26) flow away from a U-shaped structure to the casting surface (20) which is in a running state; a strip stock product which is directly cast is provided.

Description

Method and device of continuous casting of crystal strip stock

The present invention relates to motlten metal is directly cast the method and apparatus of the cast strip of continuous metal alloy.Especially relate to motlten metal is infeeded in the uncovered casting container, be fed on the casting surface of an operation, make melt metal be solidified into the satisfactory continuous band of thickness through the outlet of casting container.

In the production of general sheet metal strip, in order to produce the gratifying cast strip of thickness and quality, said method should may further comprise the steps, the form that elder generation casts ingot blank, billet or slab with motlten metal, comprise the typical hot rolling of one or many and cold rolling then, and the pickling and the annealing in process of in each different procedure of processing, being carried out.Some procedure of processing by in the cancellation conventional method can reduce the cost of producing continuous cast strip, especially casts out the cast strip of thickness range between 0.010 inch to 0.100 inch (0.0254 to 0.254 centimetre).The band that casts out usually can be with cold rolling, pickling and heat-treating methods, and being processed into final thickness is 0.002-0.040 inch (0.0508 to 1.016 millimeter).

Directly the casting slivering production method and device, known have multiple.Wherein typical method comprises, motlten metal is sprayed from the aperture of a metering, passes the gap one, is incident upon a Quench surface of rapid operation, for example a wheel or continuous belt; With the Quench surface portion of a rotation be immersed in certain methods in the pool of molten metal; As the Quench substrate, the metal of fusion is flowed and the certain methods of curing with the connecting band of level thereon; And with paired casting roller, and some casting methods of a pool of molten metal are arranged between roller.

Long ago, attempt already and will the direct method of casting of metal be used for coml quality and all production of good band of structure from an aperture.United States Patent (USP) 112,054 announces that on February 21st, 1871 a kind of motlten metal that makes passes an aperture, and the casting surface of a through rotation and make the method for flat low temperature welding wire.Similarly, No. 905,758, the United States Patent (USP) of being announced on December 1st, 1908 discloses a kind of method from the outlet of container than low side, and motlten metal is pulled to a casting surface.On October 24th, 1910, No. 24,320, BP is announced the method for motlten metal being made sheet or band shape, and its method is to make the melt metal tube seat of flowing through, and makes it have at least one side to contact with operating casting surface.Closer representational system is the United States Patent (USP) that is presented to King the 3rd on August 4th, 1970,522,836, disclosing a kind of material being kept with protruding meniscus from nozzle sprays, and mobile surface, make its little hole exits of crossing this jet pipe, material is constantly pulled out the method that is solidified into a kind of continuous product.Melted material in the exit maintains static balancing, and because the influence of gravity, maintenance contacts with the surface of operation continuously.On September 9th, 1980 was presented to the United States Patent (USP) 4,221,207 of Narasinmhan, had narrated under pressure, made the metal of fusion pass a jet pipe that cracks, and flow to the method on the surface of a Quench object in service.

Aperture formula casting system limits the cast thickness of light sheet material usually, and regulation is approximately less than 0.010 inch (0.0254cm) usually.It seems that this system seemingly is subjected to the restriction of size,, material can be transmitted from spray orifice transport, and can solidify because the operation on Quench surface is subjected to the restriction of material.This system is equivalent to a motlten metal pump, and the excessive motlten metal that is in molten condition is sent to the Quench surface from hole, and provides and can be emitted the required heat more heat of band that form to be suitable for.By the transfer rate that reduces metal and/or the speed of service of passing through to improve the Quench surface, can overcome above-mentioned situation, yet can reduce the specification of size.

When using aperture formula casting system, then can make quality poorer usually with making crystal strip stock at a high speed if attempt.Because, when its part still is in molten condition, promptly left the feed source when motlten metal is injected in the Quench surface of high-speed cruising or wide flows fullly on the level band time.This situation is the reason that causes quality to reduce, because when this band solidifies from the one side on Quench surface is rapid, shrinkage can take place, can only regulate with the motlten metal of fresh supply.The motlten metal that lacks above-mentioned fresh supply, crack enlarge in the inside configuration of band rapidly, and reduce its physical property widely.In order to overcome the problem that is occurred with aperture formula casting, all once made great efforts to improve the geometric figure of nozzle for the 4th, 290, No. 476 as No. the 4th, 274,473, the United States Patent (USP) of being announced on June 23rd, 1981 and the United States Patent (USP) of being announced on September 22nd, 1981.The shortcoming of this aperture formula casting is that this aperture has been measured a certain amount of motlten metal, and on effect, this a surname's motlten metal has been determined the dimensions of band.In addition, higher for enough motlten metals are conducted to the pressure head of using in the aperture place, simultaneously, cast wheel is relatively smaller for the projection distance of containing motlten metal, has limited the thickness of band equally.

Thicker band can be produced with a simple Quench surface, for example a Quench wheel that slowly rotates is soaked in into a kind of motlten metal of regular supply, makes it be solidified into much thick band.Motlten metal solidifies on this wheel surface, and continues thickening by foreseeable speed, till it exposes from pool of molten metal or leaves the bathing pool surface.The crackle that the motlten metal of fresh supply can avoid the general curing because of limited cast layer to cause, for example crackle that in the cellular type casting, occurs.In addition, the extremely steep thermograde between fusion pool and the curing face equally directly makes internal structure more even, makes the superior in quality of upper surface.The shortcoming of this dipping systems is, is difficult to stop the curing of the motlten metal at the Quench wheel edge of dipping a little, and the tendency of casting a kind of slot type structure is arranged simultaneously.In addition, when it enters fusion pool, the band in more being difficult to guarantee solidify and the even contact of Quench wheel surface, and make surface, casting limit of poor quality of band.Above-mentioned difficulties causes the many localized variation of band aspect size, when generating the band of thinner thickness there, is because the tightness degree of contact reduces or loses.

Once advised method, but do not develop into the coml method as yet with other direct casting.For example, with the top that melt metal is annotated the cast wheel that is in operation, make the uneven band of yardstick, seamed edge is relatively poor, and is off quality.On May 30th, 1911, United States Patent (USP) is announced a kind of device the 993rd, No. 904, and this device comprises the main container of the motlten metal of band gravity flow outlet, opening leads to the lower curtate of the container of another disc type, and the disc type container is positioned at face under wherein the molten metal level face.Motlten metal with the mode of overflow by and leave second container, motlten metal is transported on the cast wheel.No. the 3rd, 381,739, the United States Patent (USP) of delivering May 7 nineteen sixty-eight discloses the method for utilizing flowing liquid to constitute sheet or strip material, and this fluid is flowed through the surface that a quilt is got wet, and crosses over this distance and flow to the casting face of operation, and solidifies on this casting face.

Neededly be, in commodity production, can directly cast a kind of useful method of band, make the surface quality of the band of being cast and band that conventional method makes equally matched or relatively good.Directly the method and apparatus of cast should be produced the method than the casting of aperture formula and other known direct castings, comprises the casting system of soaking, the good band of band that level is cast with Quench system and two casting rolls etc. continuously.Purpose is to utilize this method and device to overcome shortcoming in the known direct pouring method.In addition, need a kind of method and apparatus, the thickness of strip that direct pouring is become relatively is approximately 0.100 inch (0.254cm) or thicker by bringing up to greater than 0.010 inch (0.0254cm).For structure and the surface quality of improving band, hope will cause the factor in the band shrinkage of directly casting and crack to reduce to minimum or eliminate.In addition, uncommon can have a kind of method and apparatus that is suitable for commercial manufacturing band, can reduce funds, can simplify the production of new alloy simultaneously.This band of directly casting should have favorable surface quality, edge and structure, and the band with general is the same good at least for its performance simultaneously.

According to the present invention, a kind of method is provided, can directly melt metal be cast continuous crystal strip stock.The method comprises, melt metal infeeded in the casting container of the receiving terminal of a tool and a port of export, and the close casting surface of the port of export, and have the edge parallel with casting plane, this casting surface moves up usually, crosses the port of export.Motlten metal is to transport to the port of export from receiving terminal, and making provides a pond can evenly flow and have the motlten metal of free upper surface in the port of export.Motlten metal flows to casting surface from the port of export, cross the width of the port of export of casting container, and the basic motlten metal that evenly flows is appeared on the casting surface.The meniscus that the surface tension of mobile metal forms constitutes the whole surface of cast strip.The meniscus that surface tension on the pool of molten metal scope of freedom forms constitutes the end face of cast strip, and leaves the edge that meniscus that the surface tension of motlten metal of the side of the port of export forms constitutes band.The surface tension of motlten metal of leaving the bottom of the port of export makes within the portion of outlet bottom and keeps a meniscus between the surface and casting face, constitutes the bottom surface of band.In order to keep surface tension, should control motlten metal in the height of the port of export and the distance between this container and the casting surface.Remove on the Strip casting surface that will cast out.

A kind of device is arranged, motlten metal directly can be cast continuous crystal strip stock equally, its composition comprises a movably casting surface, and casting container and some are fed to device in the casting container with melt metal.This casting container has a receiving terminal, a port of export, and this port of export is near close casting surface, the structure that a U-type is arranged usually, and the edge is arranged, and parallel with casting surface substantially, and the cross section in the middle of it is convenient to make the basic motlten metal that evenly flows to flow to the port of export from receiving terminal.The U type structure of the port of export has a diapire, and its inner sidewall surfaces is expansion upwards, makes the width between the inner surface identical substantially with the width of the band of desire casting.The port of export has a fixing width and a uniform transverse cross-sectional is arranged on a certain-length between the surface within the diapire, and being enough to from then on, the port of export provides a kind of basic motlten metal that evenly flows.Casting surface is movably, usually can move up, make it cross the casting container port of export, the distance of the distance end of the casting surface and the port of export is between 0.005 to 0.060 inch (0.013 to 0.152cm), from then on the speed casting of 20 to 500 inches of per minutes (be 6.1-15.4 rice/minute).

It is a kind of according to the made band of the present invention's method that the present invention provides equally.

The present invention gives more detailed narration with reference to the accompanying drawings, wherein: one

Fig. 1 is the present invention's Strip casting device schematic diagram,

Fig. 2 be the present invention device casting container face sectional drawing,

Fig. 2 a is the detail drawing of facing of Fig. 2,

Fig. 2 b is another detailed view of Fig. 2,

Fig. 3 is a view on the casting container among Fig. 2,

Fig. 3 a is the side view of the casting container among Fig. 3,

Fig. 4 is in the device of the present invention, the concrete casting container of being recommended face sectional drawing,

Fig. 5 recommends among Fig. 4, view on the concrete casting container,

Fig. 6 is in the present invention's the device, recommended, and the front view of the amplification of the port of export of concrete casting container,

Fig. 7 is the microphotograph of 304 type alloy strip steel rolled stocks of the present invention's standard of casting, and

Fig. 8 is the microphotograph of 304 type alloys of the made standard of general hot-rolled band.

Fig. 1 illustrates that generally casting device 10 comprises the tundish 14 that transmits container 12 and feed, is fed to casting container 18 with melt metal with talking about.Directly motlten metal is cast onto on the casting surface 20 by container 18 then, make the product 15 of continuous band shape or sheet.Motlten metal 19 is fed to tundish 14 from container 12, delivers to casting container 18 again, adopt general common method.Stopping bar 16 or other instruments that is suitable for can be controlled motlten metal and flow to casting container 18, for example by spout 17.Shown in casting container 18, be level basically, a receiving terminal and one and the approaching port of export in casting surface 20 positions are arranged.

By the supply of the motlten metal of casting container 18 supply, can adopt any general method that is fit to and some cases to finish, for example, some tundish or motlten metal pump.The tundish 14 of container 12 and feed can be according to known design, and should be suitable for an amount of motlten metal is fed in the casting container 18, and band is formed at casting surface.

Casting surface 20 also can be general, and can adopt form or a cast wheel of a kind of continuous belt.The use cast wheel is better.The structure of casting surface is not critical for the purpose of the present invention, although other surface of some surface ratio can provide better result.The present invention's method and apparatus was once used the casting surface with copper, carbon steel and stainless steel.Importantly, this casting surface can move by the speed of control and cross casting container, and, satisfied Quench rate can be provided, can extract enough heats, make motlten metal be solidified into band shape.Casting surface 20 can be crossed casting container 18 and move, the scope of its translational speed is 20 Foot/minute to 500 Foot/minute (6.1 meters/minute to 152.4 meters/minute), better be 50-300 Foot/minute (FPM) (15.24-91.44 rice/minute), this speed is suitable for the production of coml crystalloid material.For for the Quench of motlten metal creates conditions, can extract heat from motlten metal, make motlten metal be solidified into crystal strip stock, casting surface 20 fully should be cooled off.Install Quench rate that 10 casting surfaces 20 are provided less than 10,000 ℃/second preferably standard be less than 2000 ℃/second.

For casting surface and casting container two important requirements are arranged, that is, the direction of motion of casting surface generally is the port of export of upwards crossing container 18, and a surface is freely arranged in the pool of molten metal of the port of export 26 of container 18.Surface freely in the pool of molten metal of the port of export, for the quality of improving band, it is very important making it that good upper surface be arranged.The meaning of " freedom " that is to say that upper surface is not subjected to the restriction of structure, does not promptly contact with the structure of container, can freely seek its simultaneously, at the horizontal plane of accepting between the part 22 and the port of export 26.Usually, the direction of casting surface track is that the direction of metal flow becomes (Fig. 2 orientation a), θ angle with horizontal plane, angle θ is about 0 ° to 135 °, and this is to measure according to formed angle between the casting surface direction of motion at the motlten metal Free Surface place of the metal flow direction of the motlten metal Free Surface of container (18) port of export (26) and the port of export (26).For a cast wheel, the track of casting surface is that the Free Surface in the port of export with container 18 is tangent.Become the angle of 0 ° or 45 ° better with horizontal plane.When using cast wheel, preferably make container be positioned at position near the quadrant on cast wheel top, when the Free Surface of motlten metal during near the apical cap of cast wheel, this angle is about 0 °.

18 couples of the present invention's of casting container method and to install 10 be very important is used Fig. 2 better, and the front view of container 18 is explained.Casting container 18 is configured near the casting surface 20, is level basically, and is to constitute with heat insulation as described below and refractory material.For with uniformly needed and improved the motlten metal that flows fully and be fed on the casting surface 20, this layout is very necessary.Container 18 is included in a receiving terminal 22 and a port of export 26 at rear portion.Preferably make cross-sectional area that the receiving terminal 22 and the port of export 26 have the substantially the same cross-sectional area or a port of export 26 than to flow to the vertical cross-sectional area of the flow direction of the port of export 26 from receiving terminal 22 big with metal.With reference to diagram, receiving terminal 22 is darker than the port of export 26, is convenient to accept motlten metal 19, for example accepts motlten metal from spout 17, and in order to improve the speed that motlten metal flows to the port of export 26.

The port of export 26 of container 18 has one usually by the represented U type structure of bottom wall portion 28 and sidewall 30, as shown in Figure 3.Sidewall 30 can have vertical inner surface 31, but is convenient to flow for metal, and surface 31 should upwards be expanded.The gradient that this is slight helps to improve metal from the flowing of the port of export, if but the gradient too greatly then may lose capillary control, and make the motlten metal overflow.The gradient of stipulating every limit is less than 10 °, and 1 °-5 ° better.

The port of export 26 comprises that common inside is the diapire 28 on plane, and its length is enough to make motlten metal to flow from the port of export full and uniformly.Best, should equal at least to hold the degree of depth of the pool of molten metal in the port of export 26 according to the measured planar wall length partly of the direction of metal flow.Preferably the ratio of the length and the degree of depth was at least 1: 1 or is bigger.Best, the port of export 26 is in the whole length of diapire 28 on plane at inner surface, should have fixing or width and height uniformly, thereby can limit a uniform transverse cross-sectional at the port of export 26.According to the distance of surface between 31 within the measured sidewall 30 of the Free Surface of pool of molten metal, as the width of the port of export 26, this width width with the band of desire casting substantially is identical.Best, the port of export 26 is put in the position near casting surface 20, make the not end or the edge of sidewall 30 and diapire 28 formed U type structures parallel with casting surface substantially.

In order to promote to accept the transitional flow between the part 22 and the port of export 26, the part 24 of a centre should be set between the receiving terminal 22 and the port of export 26, making at the port of export 26 has full and uniform flowing.Best, mid portion 24 keeps full and uniform cross-sectional area at it from accepting part 22 to the whole length of the port of export 26.Part 24 between among shown in Figure 3, its width increases gradually from receiving terminal 22 toward the port of export 26, and as shown in Figure 2, its degree of depth reduces gradually, but make the cross-sectional area on its whole length keep the diapire 32 of even mid portion 24 regulations fully, the degree of depth of container 18 is reduced gradually from receiving terminal 22 toward the port of export 26 with an inclination.Similarly, purchase a width that increases gradually, can have at least a sidewall 34 outwards to launch in the mid portion 24 for the port of export 26 from narrower receiving terminal 22 toward broad.Fig. 3 is a view on the casting container 18, and the widening of sidewall 34 of mid portion 24 is described.

Fig. 2 also illustrates and can use downflow weir or overflow plate 36 in casting container 18, for example is located in the mid portion 24 or near in 24 the remittances port of export 26, further improves mobile uniformity.Overflow plate 36 is used fire-resistant or heat-resisting material manufacturing, and also tackling motlten metal has corrosion stability.Kaowool refractory plate with the suspension of rare colloidal silica was handled has proved gratifying.Downflow weir 36 can extend to whole width or a part of width that crosses casting container 18.As shown in Figure 2, best, the horizontal plane of the motlten metal in the receiving terminal 22 of casting container 18 is roughly identical with horizontal plane at the motlten metal of the port of export 26.For the ease of promoting fully extended mobile development uniformly, and the flowing of oxide on the restriction molten metal surface and slag, downflow weir 36 is of great use, can play a part to hinder or buffering.

Fig. 2 a and 2b explanation utilize the surface tension of the motlten metal that flows to constitute the strip surface of being cast.Fig. 2 a be the part near the port of export 26 of casting surface 20 detailed face sectional drawing.When motlten metal flows from the port of export 26, form and keep a meniscus 35 within the diapire 28 of U type structure between surface and the casting surface.Constitute the surface tension of meniscus 35, constitute the bottom surface of institute's Cast Strip material 15.When motlten metal formed band, the surface tension of the Free Surface of the pool of molten metal in the port of export 26 formed a curved portion 39 at the top of the motlten metal of U type structure.

Fig. 2 b represent below the port of export 26, to be seen near the port of export 26 of casting surface 20 and the metal that is solidifying 19 between the casting surface 20.The surface tension of motlten metal 19, surface 31 near the sidewall the diapire 28 30 makes the meniscus 37 that forms a convex between the port of export 26 and the casting surface 20.

The better embodiment of casting container 18 is represented with front view 4 and top view Fig. 5 respectively.As shown in the figure, container 18 has the metallic support 38 of an outside, the lining 42 on surface within refractory thermal insulator 40 and the expression caster 18, and during the casting, this lining contacts with motlten metal.Container 18 is used refractory material and is made, and should be heat-insulating, and can prevent the corrosion of motlten metal.Casting container can safe twelve Earthly Branches on some platform that is suitable for, perhaps casting container is positioned to be suitable for the device of the position of wheeled casting surface 20.The port of export 26 of casting container 18 should have the edge 33 of anterior face or sidewall 30 and the structure that the U type is determined and constituted to diapire 28, makes it the profile similarity with casting surface.Can use simply 60 or the carborundum paper of 100-coarse sand be rotated between casting surface and the container, grind container 18 with sand paper simultaneously, make its edge parallel with wheel.The anterior face 33 usefulness zirconia adhesive of casting container 18 can be brushed then, and before casting, allow its drying.

Fig. 4 and Fig. 5 illustrate the embodiment of the present invention's casting container, can be used to cast 4 inch (10.16cm), wide band, widely reach about 13 inches (33.02cm) even can be used to cast the wide band of 48 inch (121.92cm).Whether metallic support 38 uses, and can decide according to insulating barrier 40 used material types.Insulating barrier 40 can be a kind of foamed ceramic mud insulator, then needs a kind of supporter of outside, and for example metallic support 38.In other words, if with a kind of refractory brick or refractory body piece of standard, and available adhesive is bonded into desired shape, it inside and outsidely can be carved into desired size again then, then do not need outside support 38.Container 18 also can be cast the shape of an integral body by the ceramic material that can cast.Lip-deep lining 42 is made by a kind of refractory material of preventing corrosion from molten metals of insulation too within the container 18.Have been found that the made insulation quilt of available a kind of high-alumina fiber silicate, for example the fiberfrax material was once handled to saturated with the suspension of rare colloidal silica, and profiling within casting container 18, made it dry before true the use then.

Fig. 4 and Fig. 5 show the overflow means 44 at rear portion equally, have one from sweptback surface of wall outside container 18, surface within the casting container 18.The height of overflow means 44 is determined the high depth of receiving terminal 22 open ended motlten metals, has correspondingly determined the degree of depth of the motlten metal in the port of export 26 of casting container 18 simultaneously.Overflow means 44 is convenient to control the horizontal plane of the motlten metal in the casting container 18, is very important for dimensions and the quality of controlling band.

Show also among Fig. 4 that casting container 18 also can comprise a cover part 46, be arranged in casting container 18 mid portion 24 near.Cover 46 comprises the wall 48 and 50 of downward extension, links to each other with basal surface 52.The wall 48 of extension downwards is similar to the overflow plate shown in Fig. 2 with 50.Cover 46 usually is made of a kind of refractory material of corrosion of molten-metal-resistant of insulation.Cover 46 can comprise lining, the fire-resistant insulating barrier and the metal-back of outside, and with the lining 42 of casting container 18, the metal-back 38 of refractory insulating layer 40 and outside is similar.Whole width or a part of width between cover 46 can extend to and cross among the casting container near the part 24.Cover 46 is used for keeping the heat of making container 18 motlten metals, and the motlten metal that it does not contact in the receiving terminal 22 and the port of export 26 is important, can make the pool of molten metal in the port of export 26 keep surface freely like this.What this cover also can extend to part or whole rear portion accepts part 22, so that wherein comprise protective atmosphere.

Fig. 6 illustrates another scheme, and wherein, the port of export 26 of container 18 has a kind of device, and a kind of nonoxidizing atmosphere can be provided in certain zone.This area limiting crosses the width near the U type structure of the port of export of casting surface 20 on motlten metal, have a kind of width of cloth that is used for simultaneously and penetrate the device of the motlten metal that cools off this zone.These two kinds of devices can be installed individually or be installed together.

Supply a kind of device of nonoxidizing atmosphere, the cover layer of a kind of protective cover or inert gas or reducing gas is provided in the zone above the motlten metal in the U of port of export type structure.This gas reduces as far as possible or prevents that slag and oxide surface on motlten metal from occurring or formation, avoids these oxides to be cast in the band.This nonoxidizing atmosphere can be static, or is recirculated into atmosphere.Best, with a discontiguous lid, zone on the pool of molten metal of the port of export 26 of casting container 18 is covered, and have a gas spray pipe or a row jet pipe 56 at least, the gas inertia of supply continuous-flow or reduction, and this gas flow direction is opposite with the direction of casting cast bar.Best, make the gas of feeding in this zone, impact the top of the motlten metal in the liquid cell, band is formed at this place.An available protective cover is sealed the zone on the pool of molten metal in the present embodiment, comprises the form importing of the cover layer of a kind of inert gas or reducing gas with air-flow, so that all oxides is pushed away away from the motlten metal that forms band.Along the width of band the narrow gas spray pipe 56 of one row is installed, the zone that the gas shock band of air-flow or injection is formed from this liquid pool.The guiding of jet pipe 56 is opposite with the casting direction of band and be about 20 °-30 ° better with folded angle, the plane that forms band.In order to reduce the oxide that during casting, may form as far as possible, can select with hydrogen, argon, helium and/or nitrogen as gas blanket.Should be quite slow from the gas speed of jet pipe 56 ejections, because higher gas speed can be damaged surface on the pool of molten metal, the result is damaged band.

Being used for radiation cools off the device of the motlten metal in this zone, can be included near a kind of cooling agent of supply this zone, is convenient to the heat of extracting motlten metal upper surface.Can come supply coolant by one group of pipeline or the conduit 54 that is positioned at above the melt liquid, remove the radiant heat that motlten metal is emitted.Can water or other fluid be cooling agent.Preferably provide a lid to a series of cooling water pipes 54 that are sealed in casting container 18 tops with refractory material and adhesive.When motlten metal flows to casting surface by the U type structure of the port of export 26 to motlten metal on the radiation cooling carried out of surface, improved the method for surperficial extracting heat on the motlten metal from solidify, thereby can improve the quality and the structure on surface on the band that casts out by the growth of the pine-tree structure in the control band.The quality of upper surface and structure.

Best, with the device of a kind of nonoxidizing atmosphere of supply, unite use with the device that cools off as radiation.Be used for sealing the discontiguous lid in the zone above the motlten metal of the port of export 26, comprise a cooling device, in order to the radiant heat of removing motlten metal and the device of a nonoxidizing atmosphere.Best, this lid comprises a row cooling water pipe 54 and one group of gas spray pipe 56.Inert gas in this embodies is cooled off by pipe 54, more helps removing radiant heat.The lid that cooling tube 54 is housed is sealed the zone, has reduced the formation of oxide or slag, thereby avoids it to be deposited in the strip product.

About the operating aspect of the present invention's casting device, in the production of band, before melt metal is fed casting container 18, should be earlier with container 12, tundish 14 and casting container 18 are preheated to operating temperature.Any general heater should be suitable for, and can use.The heat gun of an air-acetylene or air-natural gas is set in receiving terminal 22, simultaneously, in the forward edge of casting container U type structure a protecgulum that gives heat is installed, this U type structure will place the position near casting surface 20.When casting the stainless steel of fusion, the preheat temperature of standard is 1900-2000 °F (1038-1093 a ℃).Be preheated to after the temperature that reaches the minimum standard that is required, heat gun is removed, simultaneously container 18 is placed near the casting surface projection distance and is about 5 and 20 mils (mils) (0.127 and 0.508mm).

Directly melt metal is cast as the method for continuous alloy strip steel rolled stock, beginning is conveying bucket or the container 12 that utilizes a kind of big volume, motlten metal 19 is infeeded the tundish 14 of a feed, and then deliver in its casting container 18 of locating level substantially.Motlten metal flows to the flow of casting container 18 from the tundish 14 of feed, can control and regulate with valving, for example, with stopping bar 16, simultaneously, motlten metal passes in the receiving terminal 22 that spout 17 enters the feeding part at rear portion or casting container 18.When container 18 began to fill with melt metal, motlten metal began to flow with the direction towards the port of export of container, the part 24 of the centre of flowing through simultaneously and the port of export 26, as shown in Figure 2.Casting container 18 can flow melt metal, therefore melt metal can be transported in the port of export 26 of container 18.Can comprise downflow weir 36 in the casting container 18, as shown in Figure 2, to the effect of having flowed buffering and having regulated of motlten metal 19, purpose is to make flowing uniformly of fully having launched is arranged in the port of export 26.From receiving terminal 22 to the port of export 26, motlten metal keeps the basic cross-sectional area that flows uniformly better.Usually, the port of export 26 is wideer than receiving terminal 22, and the width of U type structure approximates the width of desiring the Cast Strip material greatly.Casting container 18 has a casting volume, and this volume is the tool gradient and the mid portion that is launched into fan-shaped.Casting container 18 should be designed to, when the width that crosses the U type structure in the port of export 26 by the port of export 26 just when motlten metal forms uniform turbulent flow, can avoid motlten metal in container, to flow across, make above-mentioned flowing of fully having launched, little from the change in flow of receiving terminal 22 on the direction of the port of export 26.The horizontal plane of the motlten metal in the port of export 26 roughly horizontal plane with receiving terminal 22 is identical, though the degree of depth of motlten metal shoals in the port of export 26.Motlten metal constantly flows on the casting surface 20 of motion from the port of export 26, and the width that makes the U type structure of crossing the port of export is to casting surface 20, and motlten metal has full and uniform flowing.Motlten metal in the port of export 26 has a upper surface tension force, and simultaneously, the motlten metal that leaves opening has the surface tension of seamed edge, and these tension force partly constitute the end face and the edge of band 15 respectively.Basal surface is formed by the surface tension of the meniscus that is constituted between the inner surface at the end of U type structure and the casting surface.

Though do not want to be limited by theory, it seems that the curing of motlten metal of leaving the port of export of container 18 is the bottom of U type opening of leaving the port of export of container 18 at motlten metal, begins when this casting surface of contact.Can utilize near the casting surface the port of export 26 that is located at container 18, band is solidified from a pond motlten metal and form certain thickness,, adopt the excessive motlten metal of supply here, the band of curing is constantly formed, leave up to casting surface till the port of export 26 of container 18.Believe, the motlten metal in an above-mentioned pond is because it contacts the casting surface 20 of this operation, be the pith that constitutes thickness of strip, having only a fraction of thickness of strip is that the motlten metal of the curing that adjacent upper portions curved surface tension force part 39 is pulled out from container 18 produces.

Estimating, maybe may be that the thickness of strip more than 80% is by being provided near the motlten metal in the pond of meniscus 35 more than 70%.The bottom of the U type structure of motlten metal from the port of export 26 of container 18 is fed to casting surface, and motlten metal begins from the bottom of pool of molten metal to solidify.

Casting surface 20 is crossed casting container 18 and is moved, normally from bottom-up the uncovered of opening of crossing of the U type opening of the port of export 26.For quality and the dimensions that reaches band, container 18 all is some predetermined factors with respect to the position of casting surface 20 and the speed of casting surface.If casting surface 20 is cast wheels, then container 18 should be put 1/4th position on cast wheel top.

According to method of the present invention, the important control to several factors is arranged, make this method have the ability casting surface quality, edge and well-formed, desired thickness range is the sheet metal strip of 0.01 to 0.06 inch (0.0254 to 0.1524cm).Control motlten metal flowing on casting surface, the speed of casting surface, from the curing of pool of molten metal bottom, and in the pond in check motlten metal the degree of depth and in order to keep the surface tension of motlten metal, needing the projection distance of control from casting surface, all is important correlative factor.

In order to understand the present invention better, provide following example.

The example I

A kind of casting container, its structure structure with shown in Figure 2 basically is identical, but has only an overflow plate 36, is located near the port of export 26, be that Kaowool refractory material with the bulk of having hardened constitutes, this refractory material is that a kind of component is the material of silicon-aluminum oxide.Once it was immersed in a kind of suspension of silica of glue, in the temperature of 250 (121 ℃), after the dried overnight, in air, dried by the fire to 2000 (1093 ℃), one hour with fire.Square is cut after the moulding, is coated with the very thin Kaowool adhesive of last layer.

Container is made the shape that conforms to shape outside this is taken turns, then, U type structure end is coated with the zirconia adhesive of last layer thin layer.Use the overflow plate of same composition.Then, with air-acetylene spray gun this casting container is heated.In the container 18, from receiving terminal 22 to the port of export 26 length be about 8.75 inches (22.23cm), the width of receiving terminal 22 is about 6.5 inches (16.5cm), and the width of the diapire 28 and the port of export 26 is about 4 inches (10.16cm).In the time of 1580 ℃, the motlten metal of 304 type alloys is emitted, infeed in the container 18, and make its degree of depth in receiving terminal 22 maintain the horizontal plane of 1.75 inches (4.45cm) approximately, simultaneously, make the degree of depth of motlten metal in the U type structure of the port of export 26 of container 18 be about 0.75 inch (1.9cm).Casting surface is a kind of cast wheel made of copper, and its width is 7 inches (17.78cm), and its diameter is about 36 inches (91.44cm), and this takes turns the cooling rate that provided approximately less than 2000 ℃/second.This cast wheel is walked the speed of 205 to 300 feet (per minute is walked 76.2 to 91.44 meters) approximately with per minute, cross the port of export of container 18 and rotate, and the interval of the cast wheel and the port of export is about 40 mils (1.016mm), constitutes to be about 40 ° θ angle.The U type structure of this container is upwards opened, and the inner surface 31 of the sidewall 30 of the port of export 26 expands outwardly or a gradient arranged.The gradient of each inner surface is about 3 °.Method according to the present invention, the motlten metal that will be approximately 25 lot numbers of 100 pounds (45.36kg) is cast, the result makes successfully that width is about 4 inches (10.16cm) and thickness is even, band between 16 to 18 mils (0.406 to 0.457mm) with level and smooth and uniform upper surface and lower surface, simultaneously, its edge is smooth, the sign that is uneven or curls do not occur.

The example II

A kind of casting container, its structure basically as shown in Figure 4, its structure is in metal-back 38, to have adorned the insulator 40 that Kaowool refractory material and aluminium oxide blister refractory material are arranged.Lining 452 is made by the fiberfrax material, eight pounds every cubic feet (128.14 kilograms/meter ³Thickness be 0.5 inch (1.27cm), once be dipped into rare gluey silica suspending agent saturated, then, drying before use.The external dimensions of the port of export of container 18 be about 15 inches (38.1cm) long and 18 inches (45.72cm) wide, and, the cross-sectional area that the container 18 past ports of export 26 have some to increase a little.The making of overflow plate 36 and riding position and example I are similar, and it is bonding with the sidewall of itself and container 18 to stick with glue agent simultaneously.The surface 31 tilts equally within the sidewall 30, or 3 ° of about deflections in each surface.Casting container is located at position near the apical cap of cast wheel, and the distance of its projection is about 35 mils (mils) (0.89mm), becomes 0 ° angle approximately with the Free Surface of motlten metal.According to the present invention, the motlten metal that the 304 type 84-97 of 500 pounds (226.8kg) are criticized casts onto on the casting surface that belongs to seamless low carbon steel pipe, the outer dia of this steel pipe is 12.75 inches (32.39 centimetres), wall thickness is 0.375 inch (0.95 centimetre), 48 inches (121.92 centimetres) are wide, and it is inner with the water spray cooling simultaneously.When beginning to cast, make this cast wheel approximately with the speed of 200 feet (FPM) (60.96 meters/minute) of per minute running 10-15 second, so that the flowing of the metal at smooth initial stage, then, make it be decelerated to 100 feet of per minutes (30.48 meters/minute), and by this fast continuous running.The degree of depth of motlten metal in the port of export 26 and receiving terminal 22 maintains 2 inches (5.08 centimetres) and 2.75 inches (6.98 centimetres) approximately.

Container 18 comprises a lid equally, and this lid has the device of a radiation cooling and is used for supplying the device of helium-atmosphere, as shown in Figure 6.The implementation method of cooling is that approximately with the flow of 3 gallons of per minutes, making recirculated water is the copper pipe of 0.375 inch (0.95 centimetre) by outer dia.

It is wide that the band that is cast out is about 13 inches (33 centimetres), has homogeneous thickness, is about 45 mils (mils) (1.143 millimeters), has the second best in quality upper surface simultaneously, that is, and and even, the level and smooth and flawless of upper surface.Then, the band that casts out usually will be immersed in nitric acid/Fluorine monohydroxide through overpickling, and shrinkage factor is about 50% cold-rolling treatment, 1950 (1065 ℃) annealing in process 5 minutes, use similar method pickling again, cold rolling then one-tenth 5 mils (0.127 millimeter) and annealing.Normal temperature mechanical property through the cast samples of annealing in process is listed in the table below, can with 304 type hot rolling bands of the annealing in process of producing with conventional method relatively.

Table

0.2% 2 inches (5.08 lis

Sample hot strength yield strength rice) elongation

（KSI） （KSI） （%）

1 104.6 44.6 52.0

2 100.8 40.8 50.0

3 100.8 40.8 49.0

4 100.0 40.0 52.5

7 102.8 42.0 55.0

8 102.0 42.0 57.5

9 103.6 44.0 52.0

10 105.2 44.0 54.5

Annotate: the kip number of every square of inch of KSI-.

The 304 type steel alloys made from general method can have normal temperature mechanical property standard or average, and wherein the hot strength of the hot rolling band of crossing through annealing in process is 43.8KSI for the 101.1KSI yield strength, and the elongation of 2 inches (5.08 centimetres) is 57%.

Fig. 7 is the microphotograph of the band cast according to the present invention, the internal structure of expression 84-52 product standard.This 304 type steel alloy being amplified 100 times, can find out the cast structure of standard, is that some small column structure cells are directionally arranged according to the direction of thickness of strip, that is, arranged to the bottom surface by end face.When the common band of this direction solidifies, from the direction unanimity of band extracting heat.The growth of the dendritic crystalline structure in the present invention's the method and apparatus control band makes the band that casts out make consistent with the band end properties that makes with common method or the better tape article of its performance with the processing method of routine.

Fig. 8 has represented to amplify the normal structure of the hot rolling band of the 304 type steel alloys that 100 times the common method of usefulness makes.

See to draw, even increase and under the situation that the width of band increases, the present invention's method and apparatus all can be cast the band of structure and better quality when the thickness of band finished product.When casting 4 to 6 inches (10.16 to 15.24 centimetres) wide band finished product, often the tendency of the edge curl that occurs no longer at the width of broad, occurs on the width of 13 inches (33.02 centimetres).It is a kind of easy and directly motlten metal is cast the continuous crystalloid sheet metal strip or the method for metallic plate that the present invention's method and apparatus provides.Eliminated because of the limited shrinkage that film hardening caused and the problem of jackknifing, and the thicker band of being cast is compared with the band made from common manufacture method, its quality is quite or better.

It seems that this method and device are useful for multiple metal and alloy, comprise stainless steel and silicon steel.

Claims (24)

1, directly molten metal casting is become a kind of method of continuous crystal metal band, comprising:

Motlten metal (19) infeeded comprise that in one of a receiving terminal (22) and port of export (26) casting container (18) receiving terminal (22), the port of export (26) wherein has edge (33) near casting surface (20), and is parallel with casting surface (20);

Usually, the casting surface of cooling (20) is upwards to cross the port of export (26) and move; It is characterized in that

From receiving terminal (22) with delivery of molten metal to the port of export (26), make in the port of export (26) of casting container (18) to have and evenly flow and a motlten metal of upper surface is freely arranged substantially by a pond;

Motlten metal is flowed from the port of export (26) substantially equably, cross the width of the port of export (26) and flow on the operating surface (20), the meniscus that the surface tension of mobile metal forms constitutes the whole surface of desiring the Cast Strip material, the meniscus that the surface tension of the Free Surface of pool of molten metal forms, constitute the end face of band, motlten metal leaves the surface tension of the bottom of the port of export (26), make within the port of export (26) bottom (28) and keep a meniscus (35), the bottom surface of formation band bar between the surface and casting surface (20); Motlten metal leaves the meniscus that the surface tension of two sides (30) of the port of export (26) forms, and constitutes the edge of band, and the width of dual-side is substantially equal to the width of institute's Cast Strip material simultaneously;

The degree of depth of motlten metal in the port of export (26) of control container (18) and the distance between the port of export (26) and the casting surface (20), keep motlten metal at the top, the meniscus of the surface tension formation of bottom and side; And

Band (15) is removed from operating casting surface (20).

2, as the method in the claim 1, it is characterized in that from receiving terminal (22) to the process of outlet end (26) conveying molten metals, make that the molten metal bath stream in the port of export (26) is kept basic uniform transverse cross-sectional.

3, as the method in claim 1 or 2, it is characterized in that in the course of conveying of motlten metal, make receiving terminal (22) to the stream of the molten metal bath between the port of export (26), all keep basic uniform transverse cross-sectional.

4, as a kind of method in claim 1 or 2 or 3, it is characterized in that in the course of conveying of the motlten metal (19) in casting container (18), make the liquid level of motlten metal in receiving terminal (22) identical with the liquid level maintenance in the port of export (26).

5, as any method of claim 1-4, it is characterized in that in the course of conveying of motlten metal, receiving terminal (22) to the width of the stream of the molten metal bath between the port of export (26) is increased gradually, make liquid stream keep basic uniform transverse cross-sectional simultaneously.

6, as any method in the first few items claim, it is characterized in that mobile cushion of motlten metal in casting container (18), the uniformity of the liquid stream in the port of export (26) is improved.

7, as any method in the first few items claim, it is characterized in that making casting surface (20) to move, cross the structure that is generally the U type of the port of export (26) of container (18), moving direction normally from the bottom of U type structure towards the top of the port of export (26).

8, as any method in the first few items claim, it is characterized in that making casting surface (20) to move according to a track, make the direction of metal flow and the horizontal plane angle between forming 0 ° to 135 °, this is to measure according to the metal flow direction of the motlten metal Free Surface of the port of export of container (18) (26) and the angle between the casting surface direction of motion at the motlten metal Free Surface place of the port of export (26).

9,, it is characterized in that the described angle that is become with horizontal plane is 0 ° to 45 ° as the method in the claim 8.

10,, it is characterized in that the thickness of controlling band (15) by the speed and the degree of depth of the motlten metal (19) in the port of export (26) of container (18) of control casting surface (20) as any method in the first few items claim.

11,, it is characterized in that finishing the curing of crystalloid metal according to the motlten metal cooling after will contacting with casting surface (20) less than 2000 ℃ cooling rate each second as any method in the first few items claim.

12, as the method in the claim 11, the cooling that it is characterized in that be by each second the cooling rate less than 1500 ℃ carry out.

13,, it is characterized in that casting surface is that speed by 20 to 500 feet of per minutes (6.096 to 152.4 meters) moves as any method in the first few items claim.

14, as any method in the first few items claim, it is characterized in that providing the parallel casting surface in edge (33) with outlet end (26), and between the casting surface and the port of export (26) apart between 0.005 to 0.060 inch (0.127 to 1.524 millimeter).

15, as any method in the first few items claim, comprise band (15) removed from casting surface (20) that the band of formation has uniform width, its width range is between 4 to 48 inches (10.16 to 121.92 centimetres).

16, as any method in the first few items claim, it is characterized in that band (15) is removed from casting surface (20), the band of formation has homogeneous thickness, and its scope is between 0.010 to 0.100 inch (0.254 to 2.54 millimeter).

17, melt metal is directly cast the device of continuous crystal strip stock, comprising:

A movable casting surface (20);

One has a receiving terminal (22), and the casting container (18) of a mid portion (24) is arranged between a port of export (26) and the two ends;

Be used for melt metal (19) is fed to the device (12) of the receiving terminal (22) of casting container (18);

Described casting container (18) has its port of export (26),

Described casting surface (20) is movably, upwards crosses the port of export (26) of this casting container (18) usually,

It is characterized in that a U type structure and its edge (33) being arranged usually near casting surface (20), basically parallel with casting surface (20), mid portion (24) helps motlten metal (19) to flow to the port of export (26) from receiving terminal (22) full and uniformly, the madial wall (31) that a flat diapire (28) and deflection are arranged in the U type structure of the port of export (26), upwards open, a width is arranged between inner surface simultaneously, basically the width with the band (15) of desire casting is identical, the port of export (26), within the sidewall (30) of diapire (28), between the surface (31) a fixing width is being arranged, and a uniform transverse cross-sectional is arranged on a segment length of the port of export, be enough to make the motlten metal in the port of export (26) to form full and uniform flowing;

Distance between the port of export of casting surface (20) and casting container (18) is between 0.005 to 0.060 inch (0.127 to 1.524 millimeter), and the translational speed of casting surface is per minute 20-500 foot (6.096 to 152.4 meters).

18, as the device in the claim 17, it is characterized in that motlten metal at the liquid level of receiving terminal (22) with identical at the liquid level of the port of export (26).

19, as the device in claim 17 or 18, it is characterized in that mid portion (24) will be communicated with between the receiving terminal (22) and the port of export (26), towards the port of export (26) width that increases gradually and the degree of depth that shoals are gradually arranged, make the whole length of casting container (18) keep a basic uniform transverse cross-sectional.

20,, comprise the buffer board (36 or 48,50) in the casting container (18), so that the evenly generation of flowing as the device among claim 17 or 18 or 19.

21, any device in the claim of carrying as the front 17 to 20, it is characterized in that casting surface (20) has a direction of upwards moving from horizontal plane, and the metal flow direction on the Free Surface of the motlten metal of the port of export (26), be oriented in and become 0 ° to 135 ° angle with horizontal plane, this horizontal plane is between the direction of the Free Surface of the port of export (26) and casting surface.

22,, it is characterized in that what casting surface (20) was made up of the circumferential surface of the cast wheel of a rotation as any device in the claim 17 to 21.

23,, it is characterized in that the outlet end (26) of container (18) is in the position of the quadrant that is adjacent to cast wheel top as the device in claim 21 or 22.

24, as the device in claim 22 or 23, the position of outlet end (26) that it is characterized in that container (18) is near 1/4th positions on cast wheel top.

Images