CN102477513A - Preparation method of leadless free-cutting steel - Google Patents
Preparation method of leadless free-cutting steel Download PDFInfo
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Abstract
A preparation method of leadless free-cutting steel. According to the invention, a powder sintering method is adopted for production. Various powders and a binder are proportioned as follows: by weight, 0.3-0.8% of a graphite micropowder, 0.5-1.0% of the binder zine stearate, 0.3-0.5% of a dispersant PVA, and the balance being iron powder. The powders are mixed, pressed and sintered in the reducing atmosphere or under vacuum. The sintering technology comprises steps of: heating from room temperature to the sintering temperature of 1120-1160 DEG C for 2-5 hours, sintering for 45-75 min, and carrying out water cooling after sintering. The maximum strength of sintered steel prepared by the preparation method can reach 520.3MPa and the minimum roughness is 1.73 microns. The sintered steel is suitable for high-speed cutting process, its maximum cutting powder is 96% of that of lead free-cutting steel, and the cost of the sintered steel is 90% of that of lead free-cutting steel. Components of the product provided by the invention contain no lead and bismuth, and the product is environmentally friendly. The preparation method provided by the invention is suitable for large-scale production and requires low production cost.
Description
Technical field
The present invention is the method for manufacture of a kind of manufacturing technology of metallic substance, particularly lead free free-cutting steel.
Background technology
Along with the development of the development of mechanical workout high speed, precise treatment, robotization, particularly automotive industry, precision meter industry and household electrical appliance, the shape of various spare and accessory parts becomes increasingly complex, processing request is increasingly high.The ratio of machining cost in the component manufacturing cost is increasingly high, and sometimes even reach 40%～60% of component manufacturing cost, market presses for cutting down finished cost of the good steel of cutting ability.
In free-cutting steel, manganese sulfide is that favourable inclusion is prone to chip breaking as the internal stress concentrated source when the steel cut, and between cutter and workpiece, forms lubrication, has reduced the wearing and tearing of cutter, thereby has changed the machinability of steel.But manganese sulfide originally is a kind of harmful being mingled with in the steel, because the existence of manganese sulfide, steel makes manganese sulfide be out of shape along rolling direction in the operation of rolling, makes steel show anisotropy, has reduced the mechanical property of free-cutting steel.
Plumbous solid solubility in steel is almost nil, and generally with the inclusion metallic exist singly, perhaps attached on the inclusiones such as sulfide, the balled form with diameter 1～2 μ m exists mostly.In cutting process, plumbous particle mainly plays a part lubricated, also makes chip curling improve the chip breaking characteristic with playing embrittling effect easily.Soft and the crisp characteristic of plumbous particle can significantly reduce tool wear and improve steel surface smooth degree.But plumbous mass density is big, in steel, causes segregation easily.So the contact fatigue strength of lead and easy-cutting steel is low.So can not be used for the big component of fatigue stress load, as: gear, bearing.
Product percent of pass was low when calcium series free cutting steel was made, and cost is high.The magnesium series free-cutting steel has improved the production cost of free-cutting steel then owing to the easy oxidation of magnesium.And tellurium, selenium, titanium free-cutting steel, the tin series free-cutting steel, bismuth series free-cutting steel and, obviously improved the cost of free-cutting steel owing to added high price even expensive, rare metal, very unfavorable to its marketing.And bismuth it be not immediately clear that to the influence of human body the bismuth in some countries and regions is that the application of alloy also receives certain restriction.
In a word, it is on the low side that existing free-cutting steel all exists mechanical property, and particularly the higher problem of cost is necessary to research and develop lead free free-cutting steel cheaply.The present invention is a head it off just, has invented a kind of low-cost lead free free-cutting steel, particularly satisfies the process requirements of small articles, abnormal member.
Summary of the invention
The objective of the invention is to effectively solve the lead series free cutting steel problem of environment pollution caused; For the small-scale structure spare in fields such as household electrical appliance, precision optical machinery, instrument, automotive industry, hardware & tools provides a kind of preparation method of lead free free-cutting steel cheaply, realize unleaded, the no bismuth of lead free free-cutting steel.
Particular content of the present invention:
Iron powder kind among the present invention is the powder mix of atomized iron powder, reduced iron powder or atomized iron powder and reduced iron powder.Iron powder, graphite microparticles, dispersion agent PVA and sticker are mixed together evenly and suppress, sinter into sintered specimen or product.
Technical process of the present invention is following:
Various powder and sticker carry out proportioning by following massfraction: the massfraction of graphite microparticles is 0.3%-0.8%, and the granularity of graphite microparticles is 1-5 μ m; Sticker Zinic stearas massfraction is 0.5%-1.0%; The massfraction of dispersion agent PVA is 0.3%-0.5%; Surplus is an iron powder, the granularity of iron powder≤106 μ m.The powder batch mixing adopts V-type blender (not putting ball) or planetary type ball-milling frame (ball material mass ratio 1:8), and mixing time 5-7 hour, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 2-5 hour heat-up time; Fully remove sticker, sintering temperature 1120-1160 ℃, sintering time 45-75min; Sintering atmosphere is reducing atmosphere or vacuum, the intact back water flowing of sintering cool to room temperature.
Materials respectively and test HB, cutting ability (comprising surfaceness, surface temperature and fines per-cent) and the mechanical property (comprising tensile strength and unit elongation) of free-cutting steel.During cut all smear metals are collected, then 14 mesh standard sieves are crossed in smear metal, take by weighing the quality of all smear metals before the sieve, take by weighing the sieve quality of fines down behind the sieve, calculate fines per-cent than the total mass of smear metal with the quality of fines.
Principle of the present invention:
Plumbous solubleness in steel fusant is little, and the room temperature solid solubility in iron and steel is almost nil, so during the leaded steel melt solidifying, lead is distributed in steel with fine spheroidal particle form disperse.Lead has more crisp and soft characteristics, and on the other hand, plumbous fusing point has only 327.5 ℃; The heat of friction that when leaded steel is carried out cut, produces can make plumbous particle further softening; When leaded steel is cut, the cavity that the plumbous particle of these disperses is equivalent to exist in the steel, stress is concentrated at this easily; Produce so-called " notched effect ", thereby cause smear metal to be easy in this fracture.In addition, cutter head and smear metal contact the part because of the cut instant melting that is heated, help to change the shape of smear metal, and play the effect of lubricated cutter, can make tool bit abrasion reduce to minimum.Therefore; Plumbous cracked smear metal, minimizing bonding and seam and the raising cutting speed of in the cutting process of free-cutting steel material, playing a part can improve the efficient of cut greatly, and increase the work-ing life of cutter; Reduce the roughness of finished surface, make finished surface smooth smooth.Plumbous existence in being prone to the cutting leaded steel has conclusive effect to its cutting ability.Be employed in the small graphite microparticles of interpolation in the iron among the present invention, replace plumbous particle with graphite granule.Because the constructional feature of graphite microparticles makes them all have soft and sliding characteristic.The graphite microparticles particle that is distributed in the steel also is the equal of to have a cavity in the steel, and stress is concentrated at this easily, produces so-called " notched effect ", thereby causes smear metal to be easy in this fracture.Because the graphite microparticles particle has lubricated effect to bite, also can reduce the abrasive action of cutter head, improves cut efficient greatly.At high temperature react between graphite and the iron and generate Fe
3C, this product are a kind of brittle compounds, and be highly beneficial to adding the cutting ability that improves free-cutting steel.On the other hand, just because of the reaction between graphite and the iron, make graphite microparticles combine to form metallurgical binding with interface between the iron and steel particle, intensity is high, can improve the intensity of free-cutting steel significantly.Crucial part of the present invention is to adopt graphite microparticles, and its granularity is little, makes that in the agglomerating process, having formed a kind of centre is the little point of graphite, and the little outside of graphite coats one deck Fe
3The structure of C, this structure is to both having improved the cutting ability of free-cutting steel, to having improved its mechanical property.Because the granularity of graphite microparticles is very tiny, with blended such as iron powder, copper powder the time, is easy to occur segregation even reunites.The appearance of this phenomenon makes the mis-behave of lead free free-cutting steel, must take adequate measures to avoid.The present invention is through optimizing the consumption of dispersion agent PVA, and the segregation extent control of graphite microparticles in acceptable scope, has been optimized the cutting ability and the mechanical property of lead free free-cutting steel.
Advantage and beneficial effect
Advantage of the present invention: lead free free-cutting steel has good cutting performance, the highest 96% of the Lead Treated Steel that is equivalent to of cutting power, and maximum intensity can reach 520.3MPa, and cost is merely 90% of Lead Treated Steel, has reduced by 10%.
Embodiment
Embodiment 1:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.3%; The granularity of graphite microparticles is 5 μ m; Sticker Zinic stearas massfraction is 0.5%; The massfraction of dispersion agent is 0.3%; Surplus is an atomized iron powder.The powder batch mixing adopts V-type blender (not putting ball), mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 2 hours heat-up times; Fully remove sticker, 1120 ℃ of sintering temperatures, sintering time 45min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB71.0, and surfaceness is that raise 20.9 ℃, fines per-cent of 3.29 μ m, cutting back surface temperature are 73.5%, and cutting power is equivalent to 93% of Lead Treated Steel; Tensile strength is 220.5MPa, and unit elongation is 6.3%.Cost is 90% of a Lead Treated Steel, has reduced by 10%.
Embodiment 2:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.4%; The granularity of graphite microparticles is 4 μ m; Sticker Zinic stearas massfraction is 0.7%; The massfraction of dispersion agent is 0.37%; Surplus is a reduced iron powder.The powder batch mixing adopts V-type blender (not putting ball), mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 3 hours heat-up times; Fully remove sticker, 1130 ℃ of sintering temperatures, sintering time 55min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB96.1, and surfaceness is that raise 43.5 ℃, fines per-cent of 3.02 μ m, cutting back surface temperature are 73.1%, and cutting power is equivalent to 95% of Lead Treated Steel; Tensile strength is 305.5MPa, and unit elongation is 4.8%.Cost is 90% of a Lead Treated Steel, has reduced by 10%.
Embodiment 3:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.5%; The granularity of graphite microparticles is 2.3 μ m; Sticker Zinic stearas massfraction is 0.9%; The massfraction of dispersion agent is 0.44%; Surplus is the powder mix of atomized iron powder and reduced iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 4 hours heat-up times; Fully remove sticker, 1140 ℃ of sintering temperatures, sintering time 65min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB96.1, and surfaceness is that raise 43.2 ℃, fines per-cent of 3.33 μ m, cutting back surface temperature are 78.2%, and cutting power is equivalent to 95% of Lead Treated Steel; Tensile strength is 414.8MPa, and unit elongation is 4.5%.Cost is 90% of a Lead Treated Steel, has reduced by 10%.
Embodiment 4:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.6%; The granularity of graphite microparticles is 4 μ m; Sticker Zinic stearas massfraction is 1%; The massfraction of dispersion agent is 0.5%; Surplus is the powder mix of atomized iron powder and reduced iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 5 hours heat-up times; Fully remove sticker, 1150 ℃ of sintering temperatures, sintering time 75min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB105.6, and surfaceness is that raise 48.0 ℃, fines per-cent of 2.94 μ m, cutting back surface temperature are 72.8%, and cutting power is equivalent to 92% of Lead Treated Steel; Tensile strength is 391.1MPa, and unit elongation is 4.4%.Cost is 90% of a Lead Treated Steel, has reduced by 10%.
Embodiment 5:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.7%; The granularity of graphite microparticles is 4 μ m; Sticker Zinic stearas massfraction is 0.9%; The massfraction of dispersion agent is 0.44%; Surplus is a reduced iron powder.The powder batch mixing adopts planetary type ball-milling frame (ball material mass ratio 1:8), mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 5 hours heat-up times; Fully remove sticker, 1120 ℃ of sintering temperatures, sintering time 75min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB116.5, and surfaceness is that raise 50.4 ℃, fines per-cent of 2.71 μ m, cutting back surface temperature are 81.6%, and cutting power is equivalent to 94% of Lead Treated Steel; Tensile strength is 388.1MPa, and unit elongation is 5.1%.
Embodiment 6:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.8%; The granularity of graphite microparticles is 5 μ m; Sticker Zinic stearas massfraction is 1%; The massfraction of dispersion agent is 0.5%; Surplus is an atomized iron powder.The powder batch mixing adopts planetary type ball-milling frame (ball material mass ratio 1:8), mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 4 hours heat-up times; Fully remove sticker, 1160 ℃ of sintering temperatures, sintering time 65min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB95.0, and surfaceness is that raise 50.1 ℃, fines per-cent of 3.42 μ m, cutting back surface temperature are 73.8%, and cutting power is equivalent to 95% of Lead Treated Steel; Tensile strength is 423.8MPa, and unit elongation is 4.9%.
Embodiment 7:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.8%; The granularity of graphite microparticles is 1 μ m; Sticker Zinic stearas massfraction is 0.5%; The massfraction of dispersion agent is 0.3%; Surplus is the powder mix of atomized iron powder and reduced iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 3 hours heat-up times; Fully remove sticker, 1150 ℃ of sintering temperatures, sintering time 55min; Sintering atmosphere is a vacuum, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB92.8, and surfaceness is that raise 39.7 ℃, fines per-cent of 1.73 μ m, cutting back surface temperature are 78.8%, and cutting power is equivalent to 96% of Lead Treated Steel; Tensile strength is 520.3MPa, and unit elongation is 8.1%.
Embodiment 8:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.7%; The granularity of graphite microparticles is 2.3 μ m; Sticker Zinic stearas massfraction is 0.7%; The massfraction of dispersion agent is 0.37%; Surplus is a reduced iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 2 hours heat-up times; Fully remove sticker, 1160 ℃ of sintering temperatures, sintering time 45min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB104.3, and surfaceness is that raise 45.3 ℃, fines per-cent of 2.61 μ m, cutting back surface temperature are 72.9%, and cutting power is equivalent to 93% of Lead Treated Steel; Tensile strength is 450.4MPa, and unit elongation is 4.4%.
Embodiment 9:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.6%; The granularity of graphite microparticles is 1 μ m; Sticker Zinic stearas massfraction is 1%; The massfraction of dispersion agent is 0.5%; Surplus is the powder mix of atomized iron powder and reduced iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 3 hours heat-up times; Fully remove sticker, 1140 ℃ of sintering temperatures, sintering time 55min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB100.7, and surfaceness is that raise 46.3 ℃, fines per-cent of 2.97 μ m, cutting back surface temperature are 76.1%, and cutting power is equivalent to 94% of Lead Treated Steel; Tensile strength is 482.1MPa, and unit elongation is 6.5%.
Embodiment 10:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.5%; The granularity of graphite microparticles is 1 μ m; Sticker Zinic stearas massfraction is 0.9%; The massfraction of dispersion agent is 0.44%; Surplus is a reduced iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 2 hours heat-up times; Fully remove sticker, 1150 ℃ of sintering temperatures, sintering time 45min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB112.2, and surfaceness is that raise 46.0 ℃, fines per-cent of 2.53 μ m, cutting back surface temperature are 73.5%, and cutting power is equivalent to 92% of Lead Treated Steel; Tensile strength is 450.1MPa, and unit elongation is 2.2%.
Embodiment 11:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.4%; The granularity of graphite microparticles is 5 μ m; Sticker Zinic stearas massfraction is 0.7%; The massfraction of dispersion agent is 0.37%; Surplus is an atomized iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 5 hours heat-up times; Fully remove sticker, 1130 ℃ of sintering temperatures, sintering time 75min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB81.3, and surfaceness is that raise 50.4 ℃, fines per-cent of 3.06 μ m, cutting back surface temperature are 73.1%, and cutting power is equivalent to 93% of Lead Treated Steel; Tensile strength is 293.5MPa, and unit elongation is 3.3%.
Embodiment 12:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.3%; The granularity of graphite microparticles is 2.3 μ m; Sticker Zinic stearas massfraction is 0.5%; The massfraction of dispersion agent is 0.3%; Surplus is a reduced iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 4 hours heat-up times; Fully remove sticker, 1140 ℃ of sintering temperatures, sintering time 65min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB100.7, and surfaceness is that raise 47.0 ℃, fines per-cent of 2.46 μ m, cutting back surface temperature are 76.8%, and cutting power is equivalent to 94% of Lead Treated Steel; Tensile strength is 309.9MPa, and unit elongation is 3.7%.
Embodiment 13:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.4%; The granularity of graphite microparticles is 1 μ m; Sticker Zinic stearas massfraction is 0.7%; The massfraction of dispersion agent is 0.37%; Surplus is an atomized iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 4 hours heat-up times; Fully remove sticker, 1150 ℃ of sintering temperatures, sintering time 65min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB116.5, and surfaceness is that raise 50.4 ℃, fines per-cent of 2.25 μ m, cutting back surface temperature are 72.1%, and cutting power is equivalent to 93% of Lead Treated Steel; Tensile strength is 445.0MPa, and unit elongation is 2.3%.
Embodiment 14:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.5%; The granularity of graphite microparticles is 4 μ m; Sticker Zinic stearas massfraction is 0.5%; The massfraction of dispersion agent is 0.3%; Surplus is the powder mix of atomized iron powder and reduced iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 5 hours heat-up times; Fully remove sticker, 1130 ℃ of sintering temperatures, sintering time 75min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB132.7, and surfaceness is that raise 46.6 ℃, fines per-cent of 2.30 μ m, cutting back surface temperature are 73.3%, and cutting power is equivalent to 94% of Lead Treated Steel; Tensile strength is 343.8MPa, and unit elongation is 2.8%.
Embodiment 15:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.6%; The granularity of graphite microparticles is 1 μ m; Sticker Zinic stearas massfraction is 1%; The massfraction of dispersion agent is 0.5%; Surplus is a reduced iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 2 hours heat-up times; Fully remove sticker, 1150 ℃ of sintering temperatures, sintering time 55min; Sintering atmosphere is a reducing atmosphere, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB119.5, and surfaceness is that raise 47.7 ℃, fines per-cent of 1.95 μ m, cutting back surface temperature are 72.8%, and cutting power is equivalent to 93% of Lead Treated Steel; Tensile strength is 505.1MPa, and unit elongation is 4.5%.
Embodiment 16:
The proportioning of various powder is following: the massfraction of graphite microparticles is 0.7%; The granularity of graphite microparticles is 2.3 μ m; Sticker Zinic stearas massfraction is 0.9%; The massfraction of dispersion agent is 0.44%; Surplus is an atomized iron powder.The powder batch mixing adopts the V-type blender, mixing time 6 hours, i.e. compacting after batch mixing finishes; Promptly put into the sintering oven sintering after having suppressed, sintering process is: begin to be heated to sintering temperature from room temperature, 3 hours heat-up times; Fully remove sticker, 1160 ℃ of sintering temperatures, sintering time 45min; Sintering atmosphere is a vacuum, the intact back water flowing of sintering cool to room temperature.Carry out cutting experiment from the sampling of sintering appearance; The result finds; The HB of lead free free-cutting steel is HB112.2, and surfaceness is that raise 45.2 ℃, fines per-cent of 1.97 μ m, cutting back surface temperature are 72.8%, and cutting power is equivalent to 95% of Lead Treated Steel; Tensile strength is 498.0MPa, and unit elongation is 5.8%.
Claims (3)
1. the preparation method of a lead free free-cutting steel, it is characterized in that: sticker and various powder are carried out proportioning by following massfraction: sticker Zinic stearas, massfraction are 0.5%-1.0%; Graphite microparticles, massfraction are 0.3%-0.8%, and the granularity of graphite microparticles is 1-5 μ m; Dispersion agent PVA, massfraction are 0.3%-0.5%; Surplus is an iron powder, the granularity of iron powder≤106 μ m, mixing time 5-7 hour; Batch mixing is suppressed after finishing, and puts into the sintering oven sintering after having suppressed, and sintering process is: begin to be heated to sintering temperature from room temperature; Heated 2-5 hour, and fully removed sticker, sintering temperature 1120-1160 ℃; Sintering time 45-75min, sintering atmosphere is reducing atmosphere or vacuum, the intact back water flowing of sintering cool to room temperature.
2. the preparation method of lead free free-cutting steel according to claim 1, it is characterized in that: the granularity of described graphite microparticles is 1-4 μ m.
3. the preparation method of lead free free-cutting steel according to claim 1, it is characterized in that: the granularity of described graphite microparticles is 1-2.3 μ m.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1152624A (en) * | 1995-12-21 | 1997-06-25 | 北京科技大学 | Easy cutting iron-copper-carbon series agglutinated steel containing composite additives |
| CN1517165A (en) * | 2003-01-17 | 2004-08-04 | �ղ��Զ�����ʽ���� | Sintered body and method for manufacturing sintered body |
-
2010
- 2010-11-27 CN CN2010105614393A patent/CN102477513B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1152624A (en) * | 1995-12-21 | 1997-06-25 | 北京科技大学 | Easy cutting iron-copper-carbon series agglutinated steel containing composite additives |
| CN1517165A (en) * | 2003-01-17 | 2004-08-04 | �ղ��Զ�����ʽ���� | Sintered body and method for manufacturing sintered body |
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