CN1117529A - Prodn. art and equipment for Bainite cast-iron alloy abrasive resistant casting ball and lining board - Google Patents

Abstract

The casting ball and the lining board consist (wt.%) of C 2.2-3.7, Si 0.6-1.9, Mn 0.5-1.7, complex alloy 0.8-2.4, S<0.2, P<0.2 and the rest Fe. Before casting the ball and the lining board modification is conducted with the rare-earth alloy, so that the graphite was dispersed. After casting the isothermal quenching and tempering treatments for the casting ball are conducted, its matrix is transformed into the bainite and the complex carbonide so that it possesses higher hardness, better abrasion resistance and fatigue shock resistance. Particularly, when using vertical parting metal molding, the casting heat can be used for the heat treatment, the energy cost is decreased.

Description

Bainite alloy abrasive resistant casting ball, liner plate and production technique and equipment

The present invention relates to the production technique of a kind of wear-resistant alloy iron casting ball, liner plate and this casting ball, liner plate, and the equipment of casting this cast iron ball or liner plate.

At present, wear-resistant ball or the liner material quality of producing mainly contains following several both at home and abroad: the one, and low-alloy chilled cast iron ball or liner plate, the casting ball of this material or liner plate hardness height, percentage of damage is big, though toughness makes moderate progress after taking thermal treatment, overall performance is still relatively poor.The market that present this casting ball or liner plate capture is bigger.The 2nd, rich chromium cast iron (claiming high alloy iron again), the casting ball or the liner plate of this material, production cost height not only, and also strict to thermal treatment temp and time.If grasp is not tight, easily produce a large amount of hot tearings and fragmentation.The price of this casting ball or liner plate is generally at 6500-7300 unit/ton, and a ton cement consumption ball is generally at the 80-100 gram, and it is less relatively that face is captured in its market.The 3rd, spheroidal graphite cast iron (magnesium iron of manganese magnesium iron and other type in comprising), the casting ball or the liner plate of this material, to having relatively high expectations of spheroidization of graphite, if control is bad, the overall performance of this casting ball also is difficult to guarantee.The 4th, carbon steel forges ball or liner plate, the ball of this material or liner plate, because production cost is higher, the selling market is less.From the abrasive resistant casting ball of domestic and international production at present or the tissue of liner plate, majority is ball light body ten carbide or austenite ten carbide.Because the restriction of working condition and state of the art, the casting ball of bainite structure or the production method of liner plate yet there are no report.

The objective of the invention is in order to overcome above-mentioned deficiency, and invention has a higher hardness, wear resistance preferably, higher-strength and flexible bainite alloy abrasive resistant casting ball or liner plate, and should cast ball or the rational production technique of liner plate, particularly utilize the casting heat of casting ball or liner plate self to heat-treat, the disposable die cast equipment of producing the technology of qualified bainite structure casting ball or liner plate and producing this casting ball or liner plate.

The chemical ingredients (% by weight) of bainite alloy casting ball of the present invention or liner plate is:

C2.2～3.7；Si0.6～1.9；Mn0.5～1.7；Cu0.4～1.0

Re0.11～0.15；Sn0.1～0.4；Bi0.03～0.06；

Mo0.2～0.6 S.＜all the other Fe of 0.2 P＜0.2

Selected for this alloy casting ball or liner plate carbon, silicone content mainly is conceived to improve castability, eliminates casting flaw, obtains to perfect foundry goods to guarantee to have high mechanical property.From improving the angle of castability, determining of carbon, silicone content is to make molten iron that good mobility be arranged, and prevents to cast ball or liner plate and produces casting flaw.Because silicon is to promote graphited element, in order to prevent that this casting ball or liner plate from having more graphite to separate out in crystallisation process, under the prerequisite that guarantees the molten iron flowability, the silicon content of this casting ball or liner plate is difficult for too high, therefore the carbon content of this casting ball or liner plate is controlled at 2.2～3.7%, silicon content is controlled at 0.6～1.9%.

The main effect of manganese in this casting ball or the liner plate, the one, the deleterious effect of elimination sulphur, the 2nd, promote the formation of carbide, with hardness and the wear resisting property that improves this casting ball or liner plate.

Phosphorus all is harmful element, very easily segregation to general cast iron.Although it can form the iron phosphide eutectic tissue, have higher hardness, reach wear resistance preferably, its serious plasticity and toughness that reduces casting ball, so the content of phosphorus is controlled at below 0.2% in this casting ball.

Sulphur is the same with phosphorus, is regarded as harmful element in cast iron, although it is different with the deleterious effect mechanism of phosphorus, will control its content equally in this casting ball or liner plate, also requires its content below 0.2%.

The adding of multicomponent alloy in this casting ball or the liner plate mainly makes this casting ball or liner plate alloying, and plasticity and toughness to improve this casting ball or liner plate guarantee its heat treatment performance, to improve the intensity and the hardness of casting ball or liner plate.The for example adding of copper, molybdenum, thinning microstructure significantly improves the plasticity of matrix, and molybdenum can also promote the formation of carbide.The adding of tin can improve basic toughness, reduces hot tearing and fragmentation.The adding of bismuth can improve the heat treatment performance of matrix.Suitable retained part rare earth element in this casting ball or the liner plate, effects such as it has desulfurization, degass, purifying molten iron, it also can promote the generation of carbide simultaneously.Therefore, can bring into play the performance potential of this casting ball or liner plate more, to satisfy requirement to mechanical property by the alloying strengthening matrix.

This casting ball or liner plate not only its chemical ingredients have unique distinction, and its production technique has feature unlike the prior art equally.The production technique of this casting ball or liner plate is: the fusing of cast iron can be used cupola furnace, also can use electric furnace.The tapping temperature of its molten iron should be controlled at more than 1460 ℃, so that molten iron is carried out alloying and rotten the processing.After molten iron is come out of the stove, in molten iron, add copper, bismuth, tin, molybdenum multicomponent alloy earlier, make the molten iron alloying.When adding above-mentioned multicomponent alloy, preferably this multicomponent alloy is carried out preheating, its preheating temperature is 400-600 ℃.After making the molten iron alloying, the rare earth alloy that adds the 0.5-1.2% of weight of molten iron in molten iron again to the molten iron processing of going bad, makes this casting ball or liner plate produce a large amount of artificial nucleus in process of setting, the graphite of separating out is the disperse shape and distributes, to put forward the mechanical property of casting ball or liner plate matrix.Molten iron after rotten the processing is incubated, slag hitting is handled, and carries out the matched moulds cast then.Its teeming temperature preferably remains on more than 1400 ℃.Cast to casting ball or liner plate can be adopted metal mold, also can adopt sand mold.If use metal mold, before cast, mould is carried out preheating, sprayed coating, carry out the matched moulds cast then, wait to cast ball or liner plate after the cast and be cooled to 960～1050 ℃ of die sinkings, the casting ball or the liner plate of depanning are carried out quench treatment, make the temperature of casting ball or liner plate reduce to 800-900 ℃, be incubated 1-3.5 hour then.Can make quenching for the first time through the insulation processing, the part perlite that is become by austenitic transformation in the foundry goods is transformed into austenite again.And eliminate the internal stress of foundry goods.Through casting ball or the liner plate after the insulation, carry out the second time again and quench, make the temperature of foundry goods reduce to 500-760 ℃, and be incubated 2-4 hour.This time the purpose of quenching is that the austenitic transformation in the foundry goods is become bainite.To cast ball or liner plate then and in air, be cooled to 300-400 ℃, be incubated 4-5 hour.Insulation is this time handled, and exactly casting ball or liner plate is carried out temper, and its purpose is exactly to eliminate the internal stress of casting ball or liner plate, and the mechanical property of stable casting ball or liner plate will be cast ball at last or liner plate air cooling to room temperature gets final product.More than the quenching of said casting ball or liner plate, can be deluge quench liquid medium on Xiang Zhuqiu or the liner plate, also casting ball or liner plate can be immersed in the hardening liquid body medium.Here said quenching is preferably used salt solution, clear water or buck etc. with liquid medium.Bainite alloy abrasive resistant casting ball or liner plate have so just been made.

If advance cast with sand mold, wait to cast unpacking, the sand removal in ball or liner plate cooling back, with the casting ball produced or liner plate reheat to 800-900 ℃, be incubated 1-3.5 hour, make the matrix austenitizing of casting ball or liner plate, and then will cast ball or liner plate is quenched to 500-760 ℃, be incubated 2-4 hour, air cooling is incubated 4-5 hour to 300-400 ℃ again.Last air cooling to room temperature gets final product.The casting ball that casts out with sand mold or the isothermal quenching principle of liner plate are identical with the quenching principle of metal mold casting ball or liner plate, have also just given unnecessary details no longer one by one here.Casting ball or liner plate resultant product after isothermal quenching with sand mold casting equally also are bainite alloy abrasive resistant casting ball or liner plate.

Casting ball or the liner plate produced are confirmed that after metallurgical analysis its metallographic structure is: bainite ten multicarbides.The graphite that exists in matrix distributes with the disperse shape.The hardness HRC47-60 of this casting ball or liner plate after tested.Antifatigue impact value (number of times): 〉=20000 times.The standard and the test method of the antifatigue impact value of this casting ball, be to be undertaken by the standard and the method for preceding West Germany, preceding West Germany test method and standard are: with Φ 70mm ball is standard, at the height of 4.6M, free-falling on anvil 7000 times is not ftractureed, not broken, indeformable for qualified.

Fig. 1 is that this bainite alloy abrasive resistant casting ball or liner plate amplify 200 times metallographic structure;

Fig. 2 is that this bainite alloy abrasive resistant casting ball or liner plate amplify 600 times metallographic structure.

Pattern Bainite Alloy Antiwear cast iron ball or the liner plate produced through above proportioning and technology Have the hardness height, wearability is good, and the antifatigue impact property is good, and technology is simple, broken Broken rate is little, low cost and other advantages, cast ball or the lining particularly produced through metal casting Plate, it utilizes the afterheat in casting of cast ball or liner plate, and cast ball or liner plate are carried out the heat place Reason, the energy savings that it can be a large amount of, the production cost of reduction cast ball or liner plate. According to evidence: one ton of Pattern Bainite Alloy abrasive resistant casting ball of every production or liner plate, can save Electricity 96.7%, energy savings 97.4%, the 400-500 unit that reduces cost is by producing 1000 tons production scale, but reduce cost 76.5%. In addition, the heat treatment worker In the order, the insulation of cast ball or liner plate is processed and can be replaced traditional handicraft with the insulation kiln Employed salt bath furnace, this just can save more than 20,000 yuan of equipment investment. Moreover say, Utilize the heat of the casting of cast ball or liner plate self, cast ball or liner plate are carried out the heat place Reason obtains the bainite structure state, and it can also the shortening heat treatment cycle, reduces labor Fatigue resistance, and reduce foundry scrap and heat treatment waste gas to the pollution of environment.

For the afterheat in casting that utilizes cast ball or liner plate is processed it, at this moment casting Ball or liner plate should adopt metal type cast. Realization cast ball or liner plate metal type cast Casting Equipment is: cover half is fixedly mounted on an end of casting machine lathe bed, and dynamic model is installed On the guide rail of casting machine lathe bed, the dynamic model of this metal mold and cover half adopt vertical-parting. Its sprue, cross gate, die cavity are located at respectively on dynamic model and the cover half. Here said Die cavity, cast ball is ball-type, the casting liner plate be the shape of liner plate. For the ease of casting mold In the exhaust of when cast, mold is provided with on steam vent or two molds therein All be provided with steam vent. For the ease of die sinking and matched moulds, at the other end of casting machine lathe bed Be installed with the clamping of dynamic model, so just consisted of this Casting Equipment.

This Casting Equipment is by the casting machine lathe bed, and cover half, dynamic model and clamping form, Its equipment simple in structure, manufacturing cost is lower. Because adopting, this Casting Equipment hangs down Straight somatotype, the operation of its matched moulds, die sinking and cast and taking-up foundry goods be relatively letter all Just, for cast ball or casting liner plate provide a kind of desirable Casting Equipment, because this casting The steam vent of type is offered rationally, can prevent effectively that cast ball or liner plate from producing casting Defective realizes no riser gating, improves the utilization rate of molten iron.

Fig. 3 is this Casting Equipment front view:

Fig. 4 is the top view of this Casting Equipment:

Fig. 5 is the A-A sectional view of Fig. 3.

Below in conjunction with accompanying drawing this casting equipment is described in detail: the lathe bed of this casting machine (1) is the supporting basis of this casting equipment, its upper surface has guide rail, its cover half (2) just is fixedly mounted on its end, dynamic model (5) is installed on the guide rail of casting machine lathe bed (1), dynamic model (5) is realized the die sinking and the matched moulds of dynamic model (5) and cover half (2) in the slip of casting machine lathe bed (1).The other end of the clamping fixed installation casting machine lathe bed (1) of this casting equipment.The specific constructive form of the clamping of this casting equipment is: it can be at the hard-wired support of the other end of casting machine lathe bed (1) (8); in the groove of support (8) upper end, a handwheel (7) is installed; a leading screw (6) is installed in the threaded hole of handwheel (7), and an end of leading screw (6) is fixedlyed connected formation with the rear end of dynamic model (5).In order to realize dynamic model (5) folding automatically, handwheel (7) can be driven by power set, and at this moment, handwheel (7) can be a belt pulley, also can be gear, so that be connected with power set.The structure formation of the clamping of this casting equipment can also be: at a other end fixed installation support (8) of casting machine lathe bed (1), go up double acting cylinder of installation at support (8), this double acting cylinder can be a cylinder, also can be hydro-cylinder.The front end of the piston rod of this double acting cylinder is fixedlyed connected formation with the rear end of dynamic model (5), control the die sinking and the matched moulds of dynamic model (5) with double acting cylinder.Cover half of this casting equipment (2) and dynamic model (5) can be used the heat resisting iron manufacturing, also can make with high temperature steel or other refractory alloy.Cover half of this casting equipment (2) and dynamic model (5) adopt vertical-parting, and its sprue (4), cross gate (10), die cavity (3) are located at respectively on cover half (2) and the dynamic model (5), are best with the zygomorphy, so also help somatotype and take out foundry goods.The venting hole (9) of die cavity (3) can be located on the dynamic model (5), also can be located on the cover half (2), and can also be all to be provided with venting hole (9) on the fixed half and moving half.The position of venting hole (9) should be located at the upper end of die cavity (3).For the ease of exhaust, prevent the generation of casting flaw, venting hole (9) is extended obliquely upward by the upper end of die cavity, also can be from the upper end vertical uplift of die cavity, so that during cast, the air in the die cavity (3) is discharged rapidly from venting hole (9), casts out qualified casting ball or liner plate.

Claims (7)

1, bainite alloy abrasive resistant casting ball, liner plate is characterized in that: its chemical ingredients (weight %) is:

C2.2-3.7；Si0.6-1.9；Mn0.5-1.7；Re0.11-0.15；

Bi0.03-0.06；Sn0.1-0.4；Cu0.4-1.0；Mo0.2-0.6

S＜0.2; P＜0.2; All the other are Fe.

2, the production technique of bainite alloy abrasive resistant casting ball according to claim 1, liner plate, it is characterized in that: be that molten iron more than 1460 ℃ melts at first put into tapping temperature through the alloying element of preheating, the rare earth alloy that the adds 0.5-1.2% then processing of going bad, molten iron after rotten the processing is incubated, slag hitting, cast, treat to obtain as cast condition casting ball or liner plate after the molten iron cooled and solidified, after should casting ball or liner plate and carrying out isothermal quenching and temper, just obtain bainite alloy abrasive resistant casting ball or liner plate.

3, bainite alloy abrasive resistant casting ball according to claim 2, the production technique of liner plate, it is characterized in that: this casting ball or liner plate are poured into a mould with metal pattern, metal pattern carries out preheating before the cast, sprayed coating, matched moulds cast then, casting ball or the liner plate that obtains quenched in die sinking when treating after the cast that this casting ball or liner plate are cooled to 960-1050 ℃, makes its temperature reduce to 800-900 ℃, be incubated 1.0-3.5 hour, carry out secondary quenching again, make temperature drop to 500-760 ℃, be incubated 2-4 hour, and then air cooling is to 300-400 ℃, be incubated 4-5 hour, make its air cooling, promptly obtain bainite alloy abrasive resistant casting ball or liner plate to room temperature.

4, the production technique of bainite alloy abrasive resistant casting ball according to claim 2, liner plate, it is characterized in that: this casting ball or liner plate are poured into a mould with sand mold, carry out sand removal, cleaning after casting ball to be cast or the liner plate cooling, casting ball that will cast out or liner plate reheat are to 800-900 ℃, be incubated 1.0-3.5 hour, quench and make its temperature reduce to 500-760 ℃, be incubated 2-4 hour, air cooling is to 300-400 ℃ then, be incubated 4-5 hour, make it air cooling to room temperature, promptly obtain bainite alloy abrasive resistant casting ball or liner plate.

5, the casting equipment of bainite alloy abrasive resistant casting ball according to claim 3, liner plate; it is characterized in that: the end at casting machine lathe bed (1) is fixed with cover half (2); dynamic model (5) is installed on the guide rail of casting machine lathe bed (1); be installed with the clamping of dynamic model (5) at the other end of casting machine lathe bed (1); on cover half (2) and dynamic model (5), be provided with sprue (4), cross gate (10), die cavity (3) and venting hole (9).

6, the casting equipment of bainite alloy abrasive resistant casting ball according to claim 5, liner plate; it is characterized in that: the clamping of dynamic model (5) is installed with a support (8) for the other end at casting machine lathe bed (1); in the groove of support (8) upper end the handwheel (7) that leading screw (6) are housed in the screwed hole of centre is installed, an end of leading screw (6) is fixedlyed connected with dynamic model (5).

7, the casting equipment of bainite alloy abrasive resistant casting ball according to claim 5, liner plate; it is characterized in that: the clamping of dynamic model (5) is installed with a support (8) for the other end at casting machine lathe bed (1); in support (8) upper end a double acting cylinder is installed, the front end of double acting cylinder piston rod is fixedlyed connected with dynamic model (5).