CN103667937A

CN103667937A - Wear-resistant alloy steel material for valve bodies and preparation method thereof

Info

Publication number: CN103667937A
Application number: CN201310550365.7A
Authority: CN
Inventors: 张超
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-11-08
Filing date: 2013-11-08
Publication date: 2014-03-26

Abstract

The invention relates to a wear-resistant alloy steel material for valve bodies, which contains the following chemical elements in percentage by mass: 1.2-1.5% of carbon, 2.2-2.5% of silicon, 0.4-0.5% of manganese, 1.6-1.8% of chromium, 0.6-0.8% of copper, 1.2-1.4% of vanadium, 0.12-0.15% of boron, 0.15-0.20% of titanium, 0.1-0.15% of strontium, at most 0.030% of S, at most 0.030% of P and the balance of iron. By using the combination of the chromium, manganese, titanium and many other raw materials, the formed alloy steel has the characteristics of high strength, high hardness, favorable wear resistance and favorable corrosion resistance. Part of scrap iron is used as the raw material, and secondary refining is performed, so that the product quality is more stable and uniform. By adding the refining agent, the porosity is lowered by 1-2 degrees, and the oxide inclusions are lowered by 2 levels or so. The alloy steel is suitable for manufacturing valve bodies and is corrosion-resistant, and the service life is obviously prolonged.

Description

A kind of anti-friction alloy steel for valve body and preparation method thereof

Technical field

The present invention relates to metallic substance preparation field, relate in particular to a kind of anti-friction alloy steel for valve body and preparation method thereof.

Background technology

The development of steel alloy has had the history of more than 100 year, up to the present, diversified steel alloy is employed industrial, mainly contains with Types Below: the steel alloy of the various excellent performances such as quenched and tempered steel, spring steel, roller bearing steel, tool steel, property steel, high temperature steel, low-temperature steel.

The steel alloy that pump valve is used has varied, technology has very much progress, but still has a lot of problems to exist, as wear resistance, hardness, rustless property, corrosion resistance nature, high and low temperature resistance, fragility, toughness etc., in a lot of occasions, can't meet the requirement of production, also require further improvement, to enhance productivity, reduce costs, improve security, for high-quality precision and sophisticated technology development provides safeguard, for social development provides power, task is also very arduous.

Summary of the invention

The object of the present invention is to provide a kind of anti-friction alloy steel for valve body and preparation method thereof, this alloy material has the feature of high wear resistance, corrosion-resistant, hardness and intensity.

Technical scheme of the present invention is as follows:

An anti-friction alloy steel for valve body, is characterized in that: chemical element composition and mass percent thereof that it contains are: carbon 1.2-1.5, silicon 2.2-2.5, manganese 0.4-0.5, chromium 1.6-1.8, copper 0.6-0.8, vanadium 1.2-1.4, boron 0.12-0.15, titanium 0.15-0.20, strontium 0. 1-0.15, P≤0.030, S≤0.030, surplus are iron.

The production method of the described anti-friction alloy steel for valve body, is characterized in that:

(1), preparing the pig iron and scrap iron originates as ferrous substrate in 1:1-2 ratio, the pig iron is added to drop in stove and melt, carry out desulfurization, deoxidation, employing refining agent initial refining, add alloying constituent and carry out alloying, then add scrap iron fusing, add refining agent secondary refining, detection and adjust chemical element component content to qualified, casting, casting postheat treatment etc.;

(2) in alloying process, to the lot sequence that drops into alloying element in stove, be: (1) silicon, chromium, strontium; (2) manganese, vanadium, boron; (3) other remaining component; The timed interval that each batch drops into element is 10-13 minute, after feeding intake, stirs.

Described casting postheat treatment is: first by room temperature, with 200-230 ℃/h of speed, be warming up to 650-670 ℃, then be cooled to 550-570 ℃ with 140-160 ℃/h of speed, then continue to be warming up to 930-945 ℃ with 200-230 ℃/h of speed, insulation 3-4 hour; With 140-160 ℃/h of speed, be cooled to 720-750 ℃ again, insulation 40-60 minute, then with 140-160 ℃/h of speed, be cooled to 620-630 ℃, insulation 40-60 minute; With 100-120 ℃/h of speed, be cooled to 320-340 ℃ again, insulation 2-3 hour; With 150-170 ℃/h of speed, be warming up to 350-370 ℃ again, then be cooled to 200-230 ℃ with 50-60 ℃/h of speed, then be warming up to 530-550 ℃ with 150-170 ℃/h of speed, insulation 2-3 hour, takes out air cooling and get final product.

Described refining agent is made by the raw material of following weight part: instrument comminuted steel shot 3-4, Repone K 5-8, Calcium Fluoride (Fluorspan) 3-5, Graphite Powder 99 5-8, Sodium Silicofluoride 8-10, jade powder 3-4, montmorillonite 1-2, lazurite 3-5, potassium felspar sand 3-5, titanium dioxide 1-2, diatomite in powder 3-4, Sodium Silicofluoride 1-2, SODIUMNITRATE 2-3; Preparation method mixes each raw material, is heated to molten state, then, is poured into Quench in pure water, then is ground into 100-200 order powder; Gained powder is added and is equivalent to the silane resin acceptor kh-550 of powder weight 2-3%, the nano-carbon powder of 1-2%, after mixing, under 8-15Mpa, be pressed into base, then, at 900-950 ℃, calcine 3-4 hour, cooling after, be ground into again 150-250 order powder, obtain.

Beneficial effect of the present invention

The present invention is by using the plurality of raw materials such as chromium, manganese, titanium to combine, proportioning raw materials and production technique are rationally set, input order is rationally set, rationally controls casting postheat treatment temperature, the steel alloy of formation has high strength, high rigidity, good, the corrosion resistant feature of wear resistance; Use part scrap iron as raw material, and through secondary refining, make more stable uniform of quality, the harmful elements such as sulphur phosphorus are lower.Refining agent of the present invention is for Foundry Production, and the degree of porosity obviously improving in yield rate, particularly foundry goods reduces 1-2 degree, is controlled effectively, and can not produce pore at cast(ing) surface, and trapped oxide also obviously reduces, and oxide inclusion is 2 grades of left and right.Steel alloy of the present invention is applicable to manufacture valve body, corrosion-resistant, and obviously extend work-ing life.

Embodiment

For an anti-friction alloy steel for valve body, chemical element composition and mass percent thereof that it contains are: carbon 1.2-1.5, silicon 2.2-2.5, manganese 0.4-0.5, chromium 1.6-1.8, copper 0.6-0.8, vanadium 1.2-1.4, boron 0.12-0.15, titanium 0.15-0.20, strontium 0. 1-0.15, P≤0.030, S≤0.030, surplus are iron.

The production method of the described anti-friction alloy steel for valve body is:

(1), preparing the pig iron and scrap iron originates as ferrous substrate in 1:1 ratio, the pig iron is added to drop in stove and melt, carry out desulfurization, deoxidation, employing refining agent initial refining, add alloying constituent and carry out alloying, then add scrap iron fusing, add refining agent secondary refining, detection and adjust chemical element component content to qualified, casting, casting postheat treatment etc.;

(2) in alloying process, to the lot sequence that drops into alloying element in stove, be: (1) silicon, chromium, strontium; (2) manganese, vanadium, boron; (3) other remaining component; The timed interval that each batch drops into element is 12 minutes, after feeding intake, stirs.

Described casting postheat treatment is: first by room temperature, with 200-230 ℃/h of speed, be warming up to 660 ℃, then be cooled to 560 ℃ with 150 ℃/h of speed, then continue to be warming up to 940 ℃ with 220 ℃/h of speed, be incubated 3.5 hours; With 150 ℃/h of speed, be cooled to 730 ℃ again, be incubated 50 minutes, then be cooled to 625 ℃ with 150 ℃/h of speed, be incubated 50 minutes; With 110 ℃/h of speed, be cooled to 330 ℃ again, be incubated 2.5 hours; With 160 ℃/h of speed, be warming up to 360 ℃ again, then be cooled to 210 ℃ with 55 ℃/h of speed, then be warming up to 540 ℃ with 160 ℃/h of speed, be incubated 2.5 hours, take out air cooling and get final product.

Described refining agent by following weight part (kilogram) raw material make: instrument comminuted steel shot 3, Repone K 6, Calcium Fluoride (Fluorspan) 4, Graphite Powder 99 7, Sodium Silicofluoride 9, jade powder 3, montmorillonite 1.5, lazurite 4, potassium felspar sand 4, titanium dioxide 1.5, diatomite in powder 3.5, Sodium Silicofluoride 1.5, SODIUMNITRATE 2.5; Preparation method mixes each raw material, is heated to molten state, then, is poured into Quench in pure water, then is ground into 150 order powder; Gained powder is added and is equivalent to the silane resin acceptor kh-550 of powder weight 3%, 2% nano-carbon powder, after mixing, under 11Mpa, be pressed into base, then, at 930 ℃, calcine 3.5 hours, cooling after, then be ground into 200 order powder, obtain.

The present invention for the mechanical property of the anti-friction alloy steel of valve body is: tensile strength 1360MPa, yield strength 943MPa, unit elongation 12%, relative reduction in area 21.3%, impact absorbing energy 55J, impelling strength 64J/cm2, hardness 286HB.

Claims

1. for an anti-friction alloy steel for valve body, it is characterized in that: chemical element composition and mass percent thereof that it contains are: carbon 1.2-1.5, silicon 2.2-2.5, manganese 0.4-0.5, chromium 1.6-1.8, copper 0.6-0.8, vanadium 1.2-1.4, boron 0.12-0.15, titanium 0.15-0.20, strontium 0. 1-0.15, P≤0.030, S≤0.030, surplus are iron.

2. the production method of the anti-friction alloy steel for valve body according to claim 1, is characterized in that:

3. the production method of the anti-friction alloy steel for valve body according to claim 2, it is characterized in that: described casting postheat treatment is: first by room temperature, with 200-230 ℃/h of speed, be warming up to 650-670 ℃, with 140-160 ℃/h of speed, be cooled to 550-570 ℃ again, continue to be again warming up to 930-945 ℃ with 200-230 ℃/h of speed insulation 3-4 hour; With 140-160 ℃/h of speed, be cooled to 720-750 ℃ again, insulation 40-60 minute, then with 140-160 ℃/h of speed, be cooled to 620-630 ℃, insulation 40-60 minute; With 100-120 ℃/h of speed, be cooled to 320-340 ℃ again, insulation 2-3 hour; With 150-170 ℃/h of speed, be warming up to 350-370 ℃ again, then be cooled to 200-230 ℃ with 50-60 ℃/h of speed, then be warming up to 530-550 ℃ with 150-170 ℃/h of speed, insulation 2-3 hour, takes out air cooling and get final product.

4. the production method of the anti-friction alloy steel for valve body according to claim 2, is characterized in that: described refining agent is made by the raw material of following weight part: instrument comminuted steel shot 3-4, Repone K 5-8, Calcium Fluoride (Fluorspan) 3-5, Graphite Powder 99 5-8, Sodium Silicofluoride 8-10, jade powder 3-4, montmorillonite 1-2, lazurite 3-5, potassium felspar sand 3-5, titanium dioxide 1-2, diatomite in powder 3-4, Sodium Silicofluoride 1-2, SODIUMNITRATE 2-3; Preparation method mixes each raw material, is heated to molten state, then, is poured into Quench in pure water, then is ground into 100-200 order powder; Gained powder is added and is equivalent to the silane resin acceptor kh-550 of powder weight 2-3%, the nano-carbon powder of 1-2%, after mixing, under 8-15Mpa, be pressed into base, then, at 900-950 ℃, calcine 3-4 hour, cooling after, be ground into again 150-250 order powder, obtain.