JP6682366B2 - Method for manufacturing sliding member - Google Patents

Description

  The present invention relates to a method for producing a sliding member having high corrosion resistance and having a strong bond between the resin composition of the sliding layer and the porous portion.

  Conventionally, a sintered copper-based material having a porosity of about 5 to 25% has been used for a sliding member for a fuel injection pump. This sliding member supplies the liquid fuel from the outer peripheral surface side to the inner peripheral surface (sliding surface) side of the cylindrical sliding member through the pores existing inside the sliding member, and A fluid lubricating film of liquid fuel is formed on the surface (sliding surface) to support a shaft that rotates at high speed. Such a sintered copper-based material has a problem that the organic acid and sulfur components contained in the fuel cause corrosion of the copper alloy, and the copper-based corrosion product is mixed into the fuel. Therefore, a sintered copper-based sliding material containing Ni, Al, and Zn in order to improve corrosion resistance has been proposed (see, for example, Patent Documents 1 to 3).

  Further, conventionally, a porous sintered layer made of a copper alloy is provided on the surface of a steel backing metal via a copper plating layer, and further, the pores and the surface of the porous sintered layer are impregnated with a resin composition to form a multilayered coating. A sliding member made of a sliding material is used (for example, see Patent Documents 4 and 5). Then, a material in which such a multilayer sliding material is applied to a sliding member for a fuel injection pump has been proposed (for example, refer to Patent Document 6).

  Also, for the purpose of improving corrosion resistance under corrosive environment, instead of the conventional porous backing layer made of steel back metal and copper alloy, stainless steel powder should be bonded to the surface of the back metal layer made of stainless steel. It is proposed that a base layer is formed by stacking the base materials (for example, see Patent Document 7).

JP, 2002-180162, A JP, 2013-217493, A JP, 2013-237898, A JP, 2002-61653, A JP, 2001-355634, A JP, 2013-83304, A JP, 2005-200021, A

  By the way, although the sintered copper-based sliding materials of Patent Documents 1 to 3 have Ni, Al, and Zn contained therein to enhance corrosion resistance, corrosion of the copper alloy due to organic acids and sulfur components contained in the fuel It cannot be completely prevented. Further, the sintered copper-based sliding materials of Patent Documents 1 to 3 have low strength because they form pores in the entire sliding member, and are particularly useful for common rail fuel injection pumps and the like as shown in Patent Document 6. The load capacity of the sliding member used is insufficient.

  Further, the multi-layer sliding materials of Patent Documents 4 to 6 have a structure of a steel backing metal, and therefore have high strength. However, in the porous sintered layer made of a copper alloy, the organic acid or the sulfur component contained in the fuel or the lubricating oil causes the corrosion of the copper alloy.

  Further, it has been found that the sliding member manufactured by the manufacturing method of Patent Document 7 has improved corrosion resistance, but the bond between the underlayer and the resin composition coated on the surface of the underlayer is weak. First, in the manufacturing method of Patent Document 7, a mixed powder of a brazing filler metal powder such as a Ni brazing filler metal and stainless steel powder is sprinkled on the surface of a back metal layer made of stainless steel, and the temperature is raised to a temperature at which the brazing filler metal for bonding melts. After heating, it is cooled to form an underlayer. In addition, conventionally known brazing filler metals including this Ni brazing filler metal are eutectic alloys having a composition close to the eutectic point. The reason for this is that the eutectic alloy having a composition close to the eutectic point has a low liquidus temperature, and since the difference between the solidus temperature and the liquidus temperature is small, the heating temperature for bonding can be lowered, and This is because the brazing filler metal for bonding easily flows due to the rapid liquid phase and spreads easily on the surfaces of the objects to be bonded. That is, in the manufacturing method of Patent Document 7, since the brazing filler metal is used, the brazing filler metal rapidly becomes a liquid phase at the same time as reaching the solid phase temperature in the heating process of sintering, and becomes a mixed powder due to the influence of gravity. It flows to the interface side with the back metal layer, and near the interface side between the mixed powder and the back metal layer, the gap between the stainless steel powders is likely to be filled with the liquid phase brazing filler metal.

  However, due to the flow of the brazing filler metal liquefied in the above mixed powder to the interface side with the back metal layer, there is not enough brazing filler metal for joining the stainless steel powders on the surface side of the underlayer. Therefore, the stainless steel powders may not be joined together. To prevent this, if the proportion of the brazing filler metal in the mixed powder is increased (47 mass% or more of the brazing filler metal in the mixed powder), only minute irregularities are formed on the surface of the underlayer. The number of holes inside the underlayer is small, and the size of the holes is also small. Further, the holes inside the underlayer are often closed holes (independent holes) that do not communicate with minute recesses on the surface of the underlayer. When the surface of the underlayer is coated with the resin composition, the resin composition is simply held in contact with the uneven portion on the surface of the underlayer, and the resin composition coated on the surface of the underlayer However, the bonding between the base layer and the resin composition becomes weaker than in the case where the holes formed in the base layer in a three-dimensional network are also impregnated.

  The present invention has been made in view of the above circumstances, and an object thereof is a method for producing a sliding member having high corrosion resistance and having strong bonding between the porous portion of the sliding layer and the resin composition. To provide.

In order to achieve the above object, in the invention according to claim 1, in a method for producing a sliding member, a sliding layer including a porous portion and a resin composition is provided on a Fe or Fe alloy backing metal layer. , Fe or Fe alloy powder, and hypereutectic Ni-P alloy having an average particle size smaller than that of the Fe or Fe alloy powder and having a composition of 13 to 16% by mass, the balance Ni, and inevitable impurities. a powder, the average particle diameter is small Ni powder than the average particle diameter of該過eutectic Ni-P alloy powder, Tona is, the ratio of the Fe or Fe alloy powder in the mixed powder is 100 mass of the mixed powder It is 55 to 95 parts by mass relative to 100 parts by mass, and is included in the hypereutectic Ni-P alloy powder with respect to 100 parts by mass of the hypereutectic Ni-P alloy powder and the Ni powder in the mixed powder. So that the content of P component is 9.5 to 12.5 parts by mass Powder mixing process of preparing the powder mixture is blended, a spraying step of forming a sprayed layer by spraying the mixed powder on the Fe or Fe alloy back metal layer, said distributing layer and the Fe or Fe alloy backing The layer is sintered at a sintering temperature not lower than the liquidus temperature of the hypereutectic Ni—P alloy powder and not higher than the liquidus temperature of the hypereutectic Ni—P alloy powder + 20 ° C. and then cooled to obtain granular Fe or Fe. The porous portion comprising an alloy phase, the granular Fe or Fe alloy phases, and a Ni-P alloy phase functioning as a binder that connects the granular Fe or Fe alloy phase and the Fe or Fe alloy backing metal layer. And a sintering step of forming a sliding layer by sintering the resin composition after impregnating and coating the pores and the surface of the inside of the porous portion with the resin composition. Do Ri, the porous portion The composition of definitive the Ni-P alloy phase is characterized by consisting of from 9.5 to 12.5 wt% of P and the balance Ni and unavoidable impurities.

In the invention according to claim 2, in the manufacturing method of claim 1 Symbol mounting sliding member, the composition of the Ni-P alloy phase in the porous portion of 10 to 12 wt% P and the balance Ni and incidental It is characterized by comprising impurities.

In the invention according to claim 3 , in the method for producing a sliding member according to claim 1 or 2 , the ratio of the Ni-P alloy phase in the porous part is 100 parts by mass of the porous part. On the other hand, the Ni-P alloy phase is 5 to 45 parts by mass.

According to a fourth aspect of the invention, in the method for manufacturing the sliding member according to any of the first to third aspects, the porosity of the porous portion is 15 to 60%. To do.

  In the invention according to claim 1, the porous portion forming the sliding layer is made of a mixed powder of Fe or Fe alloy powder, hypereutectic Ni-P alloy powder, and Ni powder. After being sprinkled on the back metal layer, it is formed by heating and cooling for sintering. The porous portion is composed of granular Fe or Fe alloy phase and Ni—P alloy phase, and the Ni—P alloy phase includes hypereutectic Ni—P alloy powder of mixed powder and Ni powder. , Are reacted to form.

  In the heating process of the sintering process, when the hypereutectic Ni-P alloy powder in the scatter layer reaches the solid phase temperature, a part (mainly the surface of the powder) of each hypereutectic Ni-P alloy powder becomes liquid. Although it is phased, the P component of the Ni-P alloy liquid phase (the liquid-phased Ni-P alloy) diffuses to the surface of the Ni powder in contact with the Ni-P alloy liquid phase, and the Ni-P alloy liquid phase The Ni component on the surface of the Ni powder that contacts with the Ni-P alloy liquid phase diffuses into the Ni-P alloy liquid phase, so that the melting point of the Ni-P alloy liquid phase rises, and a part of the Ni-P alloy liquid phase solidifies and solidifies again. Be in phase. Since the Ni-P alloy liquid phase partially contains the Ni-P alloy that has become a solid phase, the flow is suppressed. In the heating process of the sintering step, the Ni-P alloy liquid phase and the Ni powder are mixed until the mixed powder reaches the sintering temperature (maximum temperature) from the solid phase temperature of the hypereutectic Ni-P alloy powder. The mutual diffusion phenomenon occurs repeatedly on the surface, and the generation and flow of the Ni-P alloy liquid phase are suppressed. For this reason, a large amount of Ni-P alloy liquid phase flows into the gaps between the granular Fe or Fe alloy phases, the pore size of the porous part after sintering becomes small, and the porosity is low. Can be prevented.

  In order to cause the above mutual diffusion phenomenon, it is necessary to use hypereutectic Ni—P alloy powder and Ni powder as raw materials. Since the hypereutectic Ni-P alloy has a large difference between the solid-phase temperature and the liquid-phase temperature, even if the hypereutectic Ni-P alloy powder reaches the solid-phase temperature during the heating process in the sintering process, some Is only in the liquid phase, and thereafter, the proportion of the liquid phase gradually increases as the heating temperature rises. Therefore, the effect of suppressing the generation and flow of the Ni-P alloy liquid phase due to the above mutual diffusion phenomenon Is obtained. Unlike the present invention, instead of the hypereutectic Ni-P alloy powder and Ni powder, a eutectic composition (Ni-11 mass% P) or a composition near the eutectic composition (Ni-9 to 12 mass% P) is used. When only Ni-P alloy powder is used, there is no difference between the solid-phase temperature and the liquid-phase temperature, or the difference is small, so that the eutectic Ni-P alloy powder is solid-phase during the heating process in the sintering process. At the same time when the temperature is reached, all or most of each eutectic Ni-P alloy powder is liquefied, and the effect of suppressing the generation and flow of the Ni-P alloy liquid phase due to the above mutual diffusion phenomenon can be obtained. Absent.

  In addition, the Ni-P alloy phase in the porous portion produced by the production method of the present invention has a uniform P component concentration in the structure. Specifically, while the above-mentioned mutual diffusion phenomenon occurs between the Ni-P alloy liquid phase and the surface of the Ni powder, the hypereutectic Ni-P alloy powder contains P component and Ni component inside and near the surface of the particle. The diffusion phenomenon of the P component and the Ni component occurs so that the concentration difference between the P component and the Ni component is eliminated. This is because the diffusion phenomenon occurs.

  In addition, the Ni-P alloy phase in the porous portion has a sintering temperature (maximum temperature) in the sintering step that is equal to or higher than the liquidus temperature of the hypereutectic Ni-P alloy powder as a raw material in order to make the structure uniform. The temperature should be Unlike the production method of the present invention, when the sintering temperature is set to a temperature lower than the liquidus temperature of the hypereutectic Ni-P alloy powder as the raw material, the Ni-P alloy in the porous portion after sintering is used. The Ni phase portion containing no P component may remain in the phase structure. When the Ni phase portion containing no P component is formed in the structure of the Ni-P alloy phase, the strength of the porous portion becomes low.

  Further, the sintering temperature in the sintering step needs to be set to a liquid phase temperature of the hypereutectic Ni—P alloy powder + 20 ° C. or less, which is the liquid phase of the hypereutectic Ni—P alloy powder. This is because if the sintering is performed at a temperature higher than + 20 ° C., the amount of the Ni—P alloy liquid phase increases during the sintering, and the porosity of the porous portion after the sintering decreases. A more preferable sintering temperature is a liquid phase temperature of the hypereutectic Ni-P alloy powder + 10 ° C or lower.

  The porous portion produced by the production method of the present invention is composed of granular Fe or Fe alloy phase and Ni—P alloy phase, and contains no Cu component, and therefore has high corrosion resistance to organic acids and sulfur components. The Ni-P alloy phase in the porous portion functions as a binder that connects granular Fe or Fe alloy phases together. In addition, the porous portion has many pores on the surface and inside, and these pores form a three-dimensional network inside the porous portion. Since the resin composition impregnates and coats the pores and the surface inside the porous portion, the resin composition and the porous portion are strongly bonded.

Further, the composition of the hypereutectic Ni-P alloy powder, of 13 to 16 wt% by comprising P and the balance Ni and unavoidable impurities, the hypereutectic Ni-P alloy powder liquidus temperature and solidus temperature and the The difference becomes large, and it becomes easy to suppress the generation and flow of the Ni-P alloy liquid phase in the sintering process.

Further, as in the invention according to claim 2 , the composition of the Ni-P alloy phase in the porous portion is 10 to 12% by mass of P, the balance is Ni, and inevitable impurities, so that the structure of the porous portion is the same. The crystal structure is mainly formed, and the strength of the porous portion is increased. When the content of the P component of the Ni-P alloy phase in the porous portion is less than 10% by mass, the proportion of the α phase (the Ni phase in which the P component is a solid solution) in the Ni-P alloy phase increases. The strength of the porous part becomes low. On the other hand, when the P component of the Ni-P alloy phase in the porous portion exceeds 12% by mass, the Ni-P alloy phase becomes too hard and the porous portion becomes brittle.

Further, as in the invention according to claim 3 , the proportion of the Ni-P alloy phase in the porous portion is 5 to 45 parts by mass with respect to 100 parts by mass of the porous portion. The strength of the porous portion is high, and a sufficient amount of holes are likely to be formed inside the porous portion. Regarding the proportion of the Ni-P alloy phase in the porous portion, when the Ni-P alloy phase is less than 5 parts by mass with respect to 100 parts by mass of the porous portion, the strength of the porous portion becomes low and When the Ni-P alloy phase exceeds 45 parts by mass with respect to 100 parts by mass, the amount of voids inside the porous part becomes small, and the bonding between the resin composition and the porous part becomes weak.

Further, as in the invention according to claim 4 , since the porosity of the porous portion is 15 to 60%, the bonding between the porous portion and the resin composition becomes particularly strong.

It is a schematic diagram which shows the cross section of the sliding member by the manufacturing method of this invention. It is a schematic diagram which shows the cross section of a spreading layer.

  The sliding member 1 in which the sliding layer 3 including the porous portion 4 and the resin composition 5 is provided on the Fe or Fe alloy backing metal layer 2 by the manufacturing method according to the present embodiment will be described with reference to FIG. To do. FIG. 1 is a schematic view showing a cross section of a sliding member 1 in which a sliding layer 3 composed of a porous portion 4 and a resin composition 5 is provided on the surface of an Fe or Fe alloy backing metal layer 2.

  As shown in FIG. 1, the sliding member 1 comprises an Fe or Fe alloy backing metal layer 2 and a sliding layer 3, and the sliding layer 3 is a porous portion formed on the Fe or Fe alloy backing metal layer 2. 4 and the resin composition 5. The porous portion 4 is composed of granular Fe or Fe alloy phase 6 and Ni—P alloy phase 7. The Ni—P alloy phase 7 serves as a binder that connects the grains of the Fe or Fe alloy phase 6 or the grains of the Fe or Fe alloy phase 6 and the surface of the Fe or Fe alloy backing layer 2. In addition, as shown in FIG. 1, the grains of Fe or Fe alloy phase 6 or the grains of Fe or Fe alloy phase 6 and the surface of Fe or Fe alloy backing layer 2 are interleaved with Ni—P alloy phase 7. Are joined together. It should be noted that the grains of the Fe or Fe alloy phase 6 or the grains of the Fe or Fe alloy phase 6 and the surface of the Fe or Fe alloy back metal layer 2 are directly or directly contacted with each other, or the portion bonded by sintering is It may be formed. Further, the grains of the Fe or Fe alloy phase 6 may have a part of the surface not covered with the Ni—P alloy phase 7. The porous portion 4 has pores for impregnating the resin composition 5, and the porosity is 10 to 60%. More preferably, the porosity is 15 to 45%.

  The composition of the Ni-P alloy phase 7 consists of 9.5 to 12.5 mass% P, the balance Ni, and inevitable impurities. The composition of the Ni-P alloy phase 7 is in a composition range in which the strength of the Ni-P alloy phase 7 becomes high. The composition of the Ni-P alloy phase 7 is more preferably 10 to 12 mass% P, the balance Ni, and unavoidable impurities.

  The proportion of the Ni-P alloy phase 7 in the porous part 4 is 5 to 45 parts by mass, more preferably 10 to 40 parts by mass, relative to 100 parts by mass of the porous part 4. Is. The proportion of the Ni-P alloy phase 7 is such that the particles of the Fe or Fe alloy phase 6 are mixed with each other, or the particles of the Fe or Fe alloy phase 6 and the surface of the Fe or Fe alloy backing layer 2 are combined to form a binder. 4 is a preferable range for forming No. 4. If the proportion of the Ni—P alloy phase 7 is less than 5 parts by mass, the strength of the porous part 4 and the bonding between the porous part 4 and the Fe or Fe alloy backing layer 2 will be insufficient. On the other hand, if the proportion of the Ni-P alloy phase 7 exceeds 45 parts by mass, the portions that should become pores during sintering will be filled with the Ni-P alloy liquid phase (liquefied Ni-P alloy). Therefore, the porosity of the porous portion 4 after sintering becomes too small.

  The granular Fe or Fe alloy phase 6 in the porous portion 4 may have an average particle size of 45 to 180 μm. Further, the composition of the granular Fe alloy is not limited. General commercially available pure iron, hypo-eutectoid steel, eutectoid steel, hyper-eutectoid steel, cast iron, high speed steel, tool steel, austenitic stainless steel, ferritic stainless steel, martensitic stainless steel, etc. Can be used. Whichever Fe alloy is used, the corrosion resistance to organic acids and sulfur components is superior to that of the conventional copper alloy. The granular Fe or Fe alloy phase 6 forming the porous portion 4 has a reaction phase with the components of the Ni—P alloy phase 7 on its surface (the surface which becomes an interface with the Ni—P alloy phase 7). It may be formed. Since the porous portion 4 is composed of such granular Fe or Fe alloy phase 6 and Ni—P alloy phase 7 and contains no Cu component, it has excellent corrosion resistance to organic acids and sulfur components. There is.

  The resin composition 5 impregnates and coats the pores and the surface inside the porous portion 4. As the resin composition 5, a general sliding resin composition can be used. Specifically, any one or more of fluororesin, polyetheretherketone, polyamide, polyimide, polyamideimide, polybenzimidazole, epoxy, phenol, polyacetal, polyethylene, polypropylene, polyolefin, polyphenylene sulfide, and solid A resin composition containing one or more of graphite, graphene, fluorinated graphite, molybdenum disulfide, fluororesin, polyethylene, polyolefin, boron nitride, and tin disulfide can be used as a lubricant. The resin composition 5 may further contain, as a filler, one or more of granular or fibrous metal, metal compound, ceramic, inorganic compound and organic compound. The resin, solid lubricant, and filler constituting the resin composition 5 are not limited to those exemplified here.

  For the Fe or Fe alloy back metal layer 2, commercially available pure iron, hypoeutectoid steel, eutectoid steel, hypereutectoid steel, cast iron, high speed steel, tool steel, austenitic stainless steel, ferritic stainless steel. Plates or strips of martensitic stainless steel or the like can be used. The Fe or Fe alloy back metal layer 2 may have a reaction phase with the components of the Ni-P alloy phase 7 formed on its surface (the surface that becomes the interface with the Ni-P alloy phase 7).

  Next, a method for manufacturing the sliding member 1 according to this embodiment will be described.

(Powder mixing process)
In the powder mixing step, Fe or Fe alloy powder 61, hypereutectic Ni-P alloy powder 71, and Ni powder 72 are mixed using a mixer such as a V blender to prepare mixed powder. . The average particle size of the Fe or Fe alloy powder 61 may be 45 to 180 μm. Further, the composition of the granular Fe alloy is not limited. Generally commercially available granular iron such as pure iron, hypo-eutectoid steel, eutectoid steel, hyper-eutectoid steel, cast iron, high speed steel, tool steel, austenitic stainless steel, ferritic stainless steel, martensitic stainless steel, etc. Powders can be used. As the hypereutectic Ni-P alloy powder 71, a hypereutectic Ni-P alloy powder manufactured by the atomization method can be used. The composition of the hypereutectic Ni-P alloy powder 71 is preferably 13 to 16% by mass of P, the balance Ni, and unavoidable impurities. Further, as the Ni powder 72, it is possible to use one made of Ni and unavoidable impurities produced by an atomizing method, an electrolytic method, a carbonyl nickel method, or the like.

  The proportion of Fe or Fe alloy powder 61 in the mixed powder is 55 to 95 parts by mass, and more preferably 60 to 90 parts by mass, relative to 100 parts by mass of the mixed powder. Further, the hypereutectic Ni—P alloy powder 71 and the Ni powder 72 in the mixed powder form the Ni—P alloy phase 7 of the porous portion 4 due to mutual diffusion of the P component and the Ni component in the sintering step described later. To do. The proportion of the hypereutectic Ni—P alloy powder 71 and the proportion of the Ni powder 72 in the mixed powder are 100% by mass of the hypereutectic Ni—P alloy powder 71 and the Ni powder 72, and the hypereutectic Ni— The P component contained in the P alloy powder 71 is determined to be 9.5 to 12.5 mass%, and more preferably 10 to 12 mass%.

  As the hypereutectic Ni-P alloy powder 71, one having an average particle diameter smaller than that of Fe or the Fe alloy powder 61 is used, and the Ni powder 72 has an average particle diameter of the hypereutectic Ni-P alloy powder 71. The average particle size is smaller than the average particle size. As the hypereutectic Ni-P alloy powder 71, one having an average particle size of 10 to 30% with respect to the average particle size of Fe or Fe alloy powder 61 is used, and the Ni powder 72 is hypereutectic Ni-. It is preferable to use one having an average particle diameter of 10 to 50% with respect to the average particle diameter of the P alloy powder 71.

(Spraying process)
In the spraying step, the prepared mixed powder is sprayed on the surface of the Fe or Fe alloy backing metal layer 2 at room temperature to form a spray layer. FIG. 2 is a schematic view showing a cross section of the dispersion layer on the Fe or Fe alloy backing layer 2. As shown in FIG. 2, the hypereutectic Ni—P alloy powder 71 and the Ni powder 72 have an average particle size smaller than the average particle size of the Fe or Fe alloy powder 61. They are in a state of coexisting in the gap between them. The Fe or Fe alloy backing layer 2 is generally commercially available as pure iron, hypoeutectoid steel, eutectoid steel, hypereutectoid steel, cast iron, high speed steel, tool steel, austenitic stainless steel, ferritic steel. Plates or strips of stainless steel, martensitic stainless steel, etc. can be used.

(Sintering process)
In the sintering step, the scatter layer and the Fe or Fe alloy backing layer 2 are heated in a reducing atmosphere in a sintering furnace or in an inert atmosphere and sintered and then cooled, and then the Fe or Fe alloy backing layer is cooled. The porous portion 4 is formed on the surface of the layer 2. The sintering temperature (maximum temperature) is a temperature within the range of the liquidus temperature of the hypereutectic Ni—P alloy powder 71 or more and the liquidus temperature of the hypereutectic Ni—P alloy powder 71 + 20 ° C. or less. Although the liquidus temperature varies depending on the content of the P component of the hypereutectic Ni-P alloy powder 71 used as a raw material, the liquidus temperature is measured by a general differential thermal analysis method, or the known Ni-P is used. The sintering temperature (maximum temperature) can be set with reference to the liquidus temperature of the alloy binary phase diagram. For example, when a hypereutectic Ni-P alloy powder 71 having a composition of Ni-15 mass% P is used, the sintering temperature (maximum temperature) is 1065 to 1085 ° C.

  As described above, the dispersion layer (mixed powder) contains the hypereutectic Ni-P alloy powder 71 and the Ni powder 72 having a large difference between the solid phase temperature and the liquid phase temperature, and these powders are Fe or Fe alloy. Since they coexist in the gaps between the powders 61, a mutual diffusion phenomenon occurs between the hypereutectic Ni-P alloy powder 71 and the Ni powder 72 in the heating process of the sintering process, and the Ni-P alloy liquid phase Generation and flow are suppressed. For this reason, a large amount of Ni-P alloy liquid phase flows into the gaps between the Fe or Fe alloy grains 61, the size of the pores of the porous portion 4 after the sintering step becomes small, and the porosity is It is prevented from becoming low. Further, the average particle size of the Ni powder 72 is made smaller than the average particle size of the hypereutectic Ni—P alloy powder 71, so that Ni that comes into contact with the Ni—P alloy liquid phase is heated in the sintering process. The surface area of the powder 72 is increased, and the above mutual diffusion phenomenon is promoted. Therefore, the Ni-P alloy phase 7 of the porous portion 4 after the sintering step has a uniform structure, and the composition of the Ni-P alloy phase 7 is 9.5 to 12.5 mass% P and the balance Ni. And unavoidable impurities. The composition of the Ni-P alloy phase 7 is in a composition range in which the strength of the Ni-P alloy phase 7 becomes high. The composition of the Ni-P alloy phase 7 is more preferably 10 to 12 mass% P, the balance Ni, and unavoidable impurities.

  The porous portion 4 is composed of granular Fe or Fe alloy phase 6 and Ni-P alloy phase 7, and the Ni-P alloy phase 7 is granular Fe or Fe alloy phases 6 or granular Fe or Fe. It functions as a binder that connects the alloy phase 6 and the surface of the Fe or Fe alloy backing metal layer 2. The proportion of the Ni-P alloy phase 7 in the porous part 4 is 5 to 45 parts by mass, and more preferably 10 to 40 parts by mass, relative to 100 parts by mass of the porous part 4. In addition, the porous portion 4 has many pores on the surface and inside, and these pores form a three-dimensional network inside the porous portion 4. The porosity of the porous portion 4 is 10 to 60%, more preferably the porosity is 15 to 45%.

(Resin firing process)
In the resin firing step, the resin composition 5 (which may be diluted with an organic solvent) prepared in advance is applied to the member having the porous portion 4 formed on the surface of the Fe or Fe alloy backing metal layer 2. The pores of the porous portion 4 are filled and impregnated so as to cover the surface of the porous portion 4. Then, this member is heated for drying and firing the resin composition 5, and the sliding layer 3 including the porous portion 4 and the resin composition 5 is formed on the surface of the Fe or Fe alloy backing metal layer 2. It is formed. The above resin composition can be used as the resin composition 5. Further, since the resin composition 5 is impregnated and coated on the pores and the surface forming the three-dimensional network inside the porous portion 4, the resin composition 5 and the porous portion 4 are bonded after the resin firing step. Becomes stronger.

  The sliding member 1 produced by the manufacturing method of the present invention can be molded into various shapes (cylindrical shape, etc.) for use.

1 Sliding member 2 Fe or Fe alloy back metal layer 3 Sliding layer 4 Porous part 5 Resin composition 6 Fe or Fe alloy phase 7 Ni-P alloy phase 61 Fe or Fe alloy powder 71 Hypereutectic Ni-P alloy powder 72 Ni powder

Claims (4)

In a method for producing a sliding member, in which a sliding layer composed of a porous portion and a resin composition is provided on an Fe or Fe alloy back metal layer,
Fe or Fe alloy powder, hypereutectic Ni-P alloy powder having an average particle size smaller than that of the Fe or Fe alloy powder and having a composition of 13 to 16 mass%, the balance Ni, and inevitable impurities When the average particle diameter is small Ni powder than the average particle diameter of該過eutectic Ni-P alloy powder, Ri Tona, the ratio of the Fe or Fe alloy powder in the mixed powder is 100 parts by weight of the mixed powder To 55 parts by mass relative to 100 parts by mass of the hypereutectic Ni—P alloy powder and the Ni powder in the mixed powder, and included in the hypereutectic Ni—P alloy powder. A powder mixing step of preparing the mixed powder in which the P component is mixed so as to be 9.5 to 12.5 parts by mass ;
A spraying step of spraying the mixed powder on the Fe or Fe alloy backing metal layer to form a spray layer;
Sintering the dispersion layer and the Fe or Fe alloy backing metal layer at a sintering temperature not lower than the liquidus temperature of the hypereutectic Ni—P alloy powder and not higher than the liquidus temperature of the hypereutectic Ni—P alloy powder + 20 ° C. After cooling, the Ni-P functions as a binder for connecting the granular Fe or Fe alloy phase, the granular Fe or Fe alloy phases to each other, and the granular Fe or Fe alloy phase and the Fe or Fe alloy backing layer. An alloy phase, and a sintering step of forming the porous portion consisting of,
A sintered resin forming the sliding layer by baking the resin composition after impregnation coating the resin composition into the pores and the surface of the interior of the porous part, Ri Tona,
The method for manufacturing a sliding member, wherein the composition of the Ni-P alloy phase in the porous portion is 9.5 to 12.5 mass% P, the balance Ni, and inevitable impurities . The composition of the Ni-P alloy phase in the porous portion, the production method according to claim 1 Symbol mounting sliding member characterized by comprising the 10-12 mass% of P and the balance Ni and unavoidable impurities. The ratio of the Ni-P alloy phase in the porous part, the Ni-P alloy phase claim 1 or claim, characterized in that 5 to 45 parts by weight per 100 parts by weight of the porous portion Item 3. A method for manufacturing a sliding member according to item 2 . The porosity of the said porous part is 15-60%, The manufacturing method of the sliding member in any one of Claim 1 thru | or 3 characterized by the above-mentioned.