354results about How to "Reduce casting defects" patented technology

The invention discloses a high-entropy alloy particle reinforced aluminum base composite material and a stirring casting preparation process thereof. The preparation process adopts mechanical alloying to prepare high-entropy alloy powder and screen to obtain high-entropy alloy particles; the high-entropy alloy particles are sealed by adopting an aluminum alloy pipe having the same material with a basal body; the aluminum alloy pipe weighed in a segmented manner is added in the molten basal body; the high-entropy alloy particles are dispersed by a stirring mode; and the high-entropy alloy particle reinforced aluminum base composite material is prepared by a casting process. The high-entropy alloy particles are 0.1-35%; aluminum alloys are 65-99.9%; and the sum of the two is 1. The high-entropy alloy particles in the structure of the prepared composite material are uniformly dispersed; the high-entropy alloy and aluminum alloy interface bonding compatibility is excellent; the strength and the toughness are excellent; the preparation process is simple; the powder has no need to be treated; the cost is low; the stability is good; and the composite material is suitable for large-batch production and standard production, and is excellent in promotion and application prospect.

The invention relates to low-cost non-rare-earth type high-strength magnesium alloy and a preparing method thereof. The alloy is Mg-Bi-Ca-Mn magnesium alloy, and is prepared from, by mass, 2-10% of Bi, 0.1-1.5% of Ca, 0.1-1.0% of Mn and the balance magnesium. The novel magnesium alloy is based on a Mg-Bi binary metal series, the element Bi serves as the main alloy element, and the Mg3Bi2 phase with high melting point is contained in the magnesium alloy. Furthermore, the magnesium alloy is evenly dispersed and distributed on a matrix through a simple alloying means, the metamorphism to a second phase by the element Ca and the element Mn and the combination of a plastic deformation processing means so that crystal boundary migration can be effectively pinned in the deformation process to hinder dislocated movement, grains are obviously refined, the strength of the alloy is greatly improved, and thus the ultra-high-strength magnesium alloy is developed in the alloy series.

The invention relates to a high-chromium cast iron composite inoculant, a preparation method and an application thereof, in particular to cast iron alloy containing chromium. The high-chromium cast iron composite inoculant is a nanocrystalline high-chromium cast iron composite inoculant containing rare-earth ferrosilicon and ferroboron. The high-chromium cast iron composite inoculant comprises Fe-Ce-Si-Ca intermediate alloy and Fe-B intermediate alloy, wherein the weight ratio between the Fe-Ce-Si-Ca intermediate alloy and the Fe-B intermediate alloy is 1:0.07-0.13. The nanocrystalline crystal grains of the inoculant are less than 100nm, the inoculant is a flaky inoculant obtained by carrying out melt fast-quenching processing on raw materials which comprise commercially purchased rare-earth ferrosilicon and commercially purchased ferroboron, the inoculant is used for carrying out crystal grain and tissue refining processing on the tissue of the high-chromium cast iron alloy of high-chromium cast iron wear parts used for engineering machinery, the processing method is a metal melt casting method, the casting defect of the existing casting technology of the high-chromium cast iron alloy is overcame, and matrix crystal grains and cementite phases are obviously refined, so that the overall mechanical properties of the high-chromium cast iron alloy are obviously improved.

The invention discloses a V8 type gray cast iron cylinder body casting pouring method which is carried out by adopting a core assembly pouring mode. The V8 type gray cast iron cylinder body casting pouring method comprises the following steps of: 1, setting a pouring position of a casting; 2, arranging a pouring system; 3, assembling a core assembly; and 4 pouring. Compared with the prior art, the V8 type gray cast iron cylinder body casting pouring method has the characteristics of relatively simple core assembly structure, high yield and low production cost.

The invention discloses a manufacturing method of a vermicular cast iron piston ring. The material of the vermicular cast iron piston ring comprises the following chemical components in percentage by weight: 3.4-4.0% of C, 2.4-3.2% of Si, not more than 0.3% of Mn, 0.2-0.4% of Cr, 0.2-0.6% of Mo, 0.5-1.0% of Cu, 0.05-0.15% of Ti, not more than 0.1% of P, not more than 0.05% of S, 0.009-0.02% of Mg and the balance of Fe and inevitable impurities. The manufacturing method of the vermicular cast iron piston ring comprises the following technical steps of moulding, smelting, casting, shaking out, shot blasting, mechanical processing, surface treatment and the like. By adopting the manufacturing method disclosed by the invention, the thinning of the piston ring is achieved, the production process is relatively simple, and the manufactured vermicular cast iron piston ring is high in elasticity, strength, toughness and wear resistance.

The invention discloses a combined pouring and purifying system for automobile aluminium alloy wheels with big diameter being more than 26 inches; the system is composed of a control cabinet, compression and decompression pipes, side dies, a top die, a bottom die, one central pouring system and two lateral pouring system; the central pouring system is composed of a circular arc filter screen, an iron pouring gate, a ceramic vacuum cup and a ceramic liquid-rising pipe; each lateral pouring system is composed of a lateral pouring feeding inlet, a cap-shaped filter screen, another iron pouring gate, another ceramic vacuum cup, a ring-shaped sealing gasket and another ceramic liquid-rising pipe; the feeding interface of each lateral pouring system is assembled at the die assembly place of two side dies and a Lip middle-upper part area; the volume of each lateral pouring feeding inlet is 100-200cm<3>; the width of the section thereof is 2.0-4.0mm, and the height thereof is 25.0-50.0mm; the invention has the characteristics that the mould filling time is short; the casting period is short; the casting defect is less; the interior quality of a casting is excellent; the casting process is convenient to control, and the like.

The invention discloses a manufacturing technology and device for an improved forged steel roller neck high nickel chrome molybdenum alloy cast composite roller. The roller comprises, by mass percent, 3.0%-3.6% of C, 0.60%-1.20% of Si, 0.30%-1.20% of Mn, 3.0%-5.0% of Ni, 1.0%-2.0% of Cr, 0.40%-1.2% of Mo, 0.1%-2% of W, 0.5%-1.0% of Cu, not larger than 0.05% of P, not larger than 0.03% of S, 0.04%-0.06% of Mg, 0.1%-0.3% of Nb, 0.1%-0.30% of Ti, 0.2%-0.6% of V, 0.05%-0.2% of B, 1.5%-2.5% of Ba, 1%-2% of Ca, 1%-3% of Sb, 0.02%-0.18% of N, 1.0%-2.0% of Y/RE and the balance Fe and inevitable micro elements. Yttrium base rare-earth nodulizing and Ba, Ca, and silicon iron composite inoculation are adopted, Nb, Ti, V, B and Sb are added for modification, and the mechanical performance of the roller is improved; by the adoption of the forged steel roller neck, the strength of the roller is improved, an induction heater is adopted to carry out in-mold whole heating casting on a core stick, a water cooled crystallizer is molded, a composite layer interface can be dynamically controlled, the technology is simple, the efficiency is high, power consumption is small, the cost is low, no composition segregation exists, and the service life of the roller is long.

The invention provides a novel modeling method for casting large-sized and ultra large-sized alloy steel track shoes. The method comprises the following steps of: placing a model on a shaping plate with a gas extracting box; covering a heated plastic film on a model form and the shaping plate; attaching the plastic film to each part of the form and the shaping plate through vacuum suction force; brushing a high temperature resistant costing on the model form attached with the plastic film; placing a sand box mounted with a gas extracting device on a model plate; forming a casting head and a gas outlet in an upper casting sand box; filling dry quartz sand into the sand box; ramming the casting sand by using a vibration table; scraping the sand model; covering an upper sealing sand box of the sand model by using a plastic film; pumping loose sand in the sand box to negative pressure so that the sand model is hardened; pulling out the hardened sand model to obtain the model form; making upper and lower sand models; setting a core; and closing the box for casting. Compared with the traditional sand model, the novel modeling method for casting the large-sized and ultra large-sized alloy steel track shoes, provided by the invention, has the following advantages that: the working environment is largely improved, the size accuracy and surface roughness of the cast are improved, long service life of the mold is obtained, the consumption of the casting sand and auxiliary materials is saved, energy is saved and emission is reduced.

The invention discloses special precoated sand for cast of high alloy material. The sand comprises roughing sand, a lubricant, an adhesive, a curing agent and a coupling agent. The adhesive is 1.7-1.9 % of the total weight of the roughing sand. The curing agent is 9-11 % of the weight of the adhesive. The lubricant is 6-8 % of the weight of the adhesive. The coupling agent is 1-2 % of the weight of the adhesive. The roughing sand comprises reclaimed sand, cerabeads, and magnetic sand. The reclaimed sand is 50-65 % of the total weight of the roughing sand. The cerabeads are 25-35 % of the total weight of the roughing sand. The magnetic sand is 10-15 % of the total weight of the roughing sand. The sand has various superior properties of high temperature resistance, high strength, low expansion, low gas release and easy collapse. The sand can guarantee that the process of cast of high alloy material can be smoothly performed, and the production efficiency is improved.

The invention discloses a smelting method for an Al-Mg-Mn-Cu-Ti aluminum alloy. The smelting method comprises the following steps of (1) preparing before smelting; (2) batching; (3) smelting, namely preheating a cast iron crucible furnace, and adding a covering agent; adding partial raw materials into a cast iron crucible after the covering agent is completely dissolved, and increasing the temperature and adding pure Mn ingots after the raw materials are completely smelted; continuously stirring and gradually increasing the temperature after the pure Mn ingots are smelted, slagging off, transferring melt to a graphite crucible heat preserving furnace, sampling and performing stokehole chemical component analysis; (4) preserving the heat and refining; namely adjusting the components of the melt, controlling the temperature of the furnace, pressing a refining agent into an aluminum alloy melt, degassing and refining; and (5) casting, namely covering a coating agent without magnesium on the surface of the aluminum alloy melt, slagging off after standing, and finally casting. The Al-Mg-Mn-Cu-Ti aluminum alloy produced by the smelting method has the advantages of less casting defects, high yield, low content of impurities of produced products, and good mechanical performance.

The invention discloses a casting forming process of a complex high temperature alloy multi-union guide vane casting, and belongs to the technical field of precision casting. The process is characterized in that a casting body wax mold is prepared, and the casting body wax mold and a rigging system are assembled into a module; the module is coated with refractory coating layer by layer, is sent into a dewaxing kettle for dewaxing, and is sent into a baking furnace for high temperature pre-baking; the exterior of a shell is wrapped in a step type and is tied with refractory insulation cotton; ahigh temperature alloy rod is remelted and smelted to obtain high temperature alloy metal liquid; before pouring, the shell is sent into the baking furnace again, and then is sent into a vacuum induction casting furnace, and the high temperature alloy metal liquid is poured into the shell; and after pouring is completed, heat preservation is carried out, and shell removal, cutting, sand blastingand polishing are carried out after furnace exiting. The casting forming process effectively reduces or eliminates casting defects such as looseness and cracking easily generated at the connecting positions of hot joint vanes and small edge plates, the yield is improved to 75% to 80%, and the process is suitable for complex high temperature alloy multi-union guide vane casting.

The invention discloses a method for improving the deformability of oxide ceramic shells precisely cast by titanium-aluminum alloy. The method comprises the steps that polypropylene fiber and graphite powder are added in the preparing process of precisely casting the shells, and combustion is achieved through high-temperature roasting of the polypropylene fiber and the graphite powder so as to form pores in the shells and improve the deformability. Particularly, in the steps of slurry preparation and slurry coating on the shells in the preparation process of precisely casting the shells, the polypropylene fiber is wound on the surfaces of the oxide shells, and back-layer slurry containing graphite powder is adopted for coating. By the adoption of polypropylene fiber winding during shell preparation and preparation of the back-layer slurry containing the graphite powder in the method, the deformability of the shells is effectively improved, accordingly the cold and hot cracking tendency occurred in the solidification process of castings is effectively reduced, and the qualified rate of the castings is improved.

The invention discloses a modified manufacturing process for a high-chromium cast iron composite roll through a forged steel roll neck and equipment. The material comprises, by mass, 3.0%-3.6% of C, 0.60%-1.20% of Si, 0.30%-1.20% of Mn, 3.0%-5.0% of Ni, 1.0%-2.0% of Cr, 0.40%-1.2% of Mo, 0.1%-2% of W, 0.5%-1.0% of Cu, 0%-0.05% of P, 0%-0.03% of S, 0.04%-0.06% of Mg, 0.1%-0.3% of Nb, 0.1%-0.30% of Ti, 0.2%-0.6% of V, 0.05%-0.2% of B, 1.5%-2.5% of Ba, 1%-2% of Ca, 1%-3% of Sb, 0.02%-0.18% of N, 1.0%-2.0% of Y/RE and the balance Fe and inevitable microelements. Yttrium-based rare earth nodulizing and compound inoculating of Ba, Ca and silicon iron are adopted, and modification treatment is conducted by adding Nb, Ti, V, B, and Sb, so that the mechanical property of the roll is improved. The strength of the roll is improved through the forged steel roll neck. Overall in-mold heating and fusion casting are conducted on a core rod through an induction heater. Forming is conducted through a water cooled crystallizer. A composite layer interface can be dynamically controlled. The process is simple, the efficiency is high, power consumption is small, the cost is low, composition segregation is avoided, and the service life of the roll is long.

The invention relates to a low-pressure cast aluminum-alloy wheel-casting sequential-solidification temperature-field compensating method, wherein the areas of a mould needing temperature compensation are found out by simulating solidification for casting before product casting, the areas are generally positioned at a top mould and a side mould according to the casting characteristics of an aluminum-alloy wheel, a heating resistance wire and a thermocouple are installed at the top mould and the side mould when the mould is developed, the heating resistance wire and the thermocouple are connected with a low-pressure casting-system control cabinet, the mould temperature is set according to the technical requirements of casting processes, and when the mould temperature reaches the technical requirements, the heating resistance wire stops working; and when the temperature is insufficient, the heating resistance wire begins to work, thereby the temperatures of the side mould and the top mould which are after-cooled are guaranteed to be balanced, the sequential solidification of molten aluminum is guaranteed, casting defects are reduced, and compared with a traditional process, the method is a more economical and practical method for guaranteeing casting sequential solidification.

The invention relates to a novel green lost foam casting technology. The core is not to let a foaming mold be gasified and disappear during the casting process but to let it defoam for recovery, utilization and discharge of polluted gases so as to reach the purpose of green environmental protection. Without the gasification of the foaming mold, casting defects (such as pore defect) can be substantially eliminated, alloy carburetting can be avoided and the casting quality can be improved. After coating the foaming mold with paint, the surface of the foaming mold is coated with a binder and sand to produce a shell with a certain thickness. After the shell is completely hardened, the foaming mold is heated for defoaming, and casting is carried out in allusion to different shapes. By a corresponding method, the defoamed residual mold is taken out to complete the shell making. Finally, direct shell casting, sand burying (common dry sand, iron shot and the like), magnetic casting and vacuum casting the like are chosen according to the tension force of a casted molten metal. The technology is green and environmentally friendly with no pollution, can be used to substantially improve the quality of the lost foam casting, and can be widely applied in the industrial production.

The invention discloses a casting method of a ZL101 thin-wall aluminium alloy part. The method includes steps of: 1) preparing moulding sand raw materials; 2) preparing binder slurry, wherein the binder slurry comprises 36-40% by weight of starch, 6-8% by weight of furan resin, 14-16% by weight of calcium bentonite, 3-5% by weight of bagasse cellulose powder having a size of -100 meshes, 1-2% by weight of zinc stearate and 2-3% by weight of sodium tripolyphosphate, with the balance being water; 3) preparing moulding sand; 4) manufacturing a casting and gating system; 5) smelting a ZL101 alloy, wherein 0.035% of Sr is added for modification, argon is fed after slag removal, gas removal is performed by rotation, smelting is performed when the temperature is 735-745 DEG C, and the alloy is allowed to stand for 10-12 min after smelting; 6) casting, wherein the aluminum alloy casting temperature is controlled to e 720-730 DEG C, and the casting speed is controlled in a manner that the former two fifth of the total casting amount adopts a speed of 6-8 kg/s, the middle two fifth adopts a speed of 4-5 kg/s, and the last one fifth adopts a speed of 6-8 kg/s; and 7) cooling with the mould, opening the mould, cleaning and performing thermal processing.

The invention belongs to the field of sand mould casting, and discloses a mouldless cast forming method of frozen clay sand. The mouldless cast forming method comprises the steps: crude sand and a clay binder are evenly mixed, moulding sand is manufactured and placed into a sand box to be compacted, a clay sand blank is manufactured and then placed into a low-temperature environment of minus 15-minus 40 DEG C to be sufficiently frozen, and after the strength and the surface hardness of the clay sand reach the index, a standby sand blank is manufactured; and a machining program is generated through a part model, a mouldless forming machine is driven to enable the frozen sand blank to be cut and assembled into a sand mould, and then the sand mould is cast under a normal-temperature or low-temperature environment. After the clay sand mould is frozen, air permeability is good, and the air hole defect in the metal liquid solidifying process is reduced; the compression-resisting (tensile) strength of the sand mould is high, the surface hardness is high, and the mouldless cast forming method is suitable for mouldless cutting forming; compared with traditional manual moulding, a mouldlessmanufacturing process of the frozen clay sand is high in efficiency and high in sand mould precision; and meanwhile, during casting, a high-temperature metal liquid melt is high in supercooling degree, thus in the metal solidifying process, the temperature gradient is large, a metal cast is compact in structure, and the mechanical property is good.

The invention relates to a two-fluid bimetal compound poured crushing hammer manufacturing method. The method comprises the steps that casting is conducted, specifically, a hammer handle pouring system and a hammer pouring system are arranged on a sand mold; high-chromium cast iron and low-carbon alloy steel are smelted, a hammer handle part adopts a low-carbon alloy steel material, and a hammer part adopts a high-chromium cast iron material; a hammer handle is poured at first, according to the weight of the hammer, after 3-15 seconds, a binding agent is added to the low alloy steel liquid surface of a sand mold cavity, and then high-chromium alloy is started to be poured; after pouring is completed, still standing is conducted, after molten steel is cooled and solidified, a semi-finished compound hammer can be obtained; and the semi-finished compound hammer is subjected to heat treatment, and the compound hammer product is obtained finally. By adding the binging agent in the process, a fusion layer which is compact in structure, free of shrinkage cavities, loose and high in strength is formed on an interface of two metals, and the binding strength of the two metals is improved.

The invention relates to high-toughness cold-hot-fatigue-resistant cast steel for a high-speed train brake disc and a preparation method thereof, belongs to the field of metal materials and preparation thereof, and solves the problem of matching of room-temperature toughness, high-temperature mechanical properties and cold and hot fatigue failure resistance of the cast steel for the high-speed train brake disc in the prior art. The high-toughness cold-hot-fatigue-resistant cast steel for the high-speed train brake disc comprises the following chemical components, in percentage by mass, of 0.20%-0.40% of C, 0.30%-0.70% of Si, 0.50%-2.00% of Mn, 0.50%-2.00% of Cr, 0.50%-2.00% of Ni, 0.40%-1.80% of Mo, 0.01%-0.30% of V, smaller than or equal to 0.015% of P, smaller than or equal to 0.010% ofS, smaller than or equal to 0.010% of O, smaller than or equal to 0.015% of N, and the balance Fe and inevitable impurities, wherein the total content of the Mn, the Cr and the Ni is 2.00%-6.00%, andthe total content of the Mo and the V is 0.41%-2.00%. Through reasonable composition, organization structure and preparation process regulation and control, excellent room-temperature toughness, high-temperature mechanical property and cold and hot fatigue failure resistance of the cast steel are matched, the requirements for comprehensive mechanical property and long service life of the cast steel brake disc of a high-speed train are met, and the cast steel is suitable for being used as a material for the cast steel brake disc of the high-speed train.