CN103014450B - Processing technology for high-performance aluminium alloy foaming mould casting - Google Patents

Abstract

The invention discloses a processing technology for a high-performance aluminium alloy foaming mould casting, and the processing technology comprises the following five steps of: burdening, smelting, casting, carrying out heat treatment and carrying out extrusion moulding. According to the processing technology disclosed by the invention, appropriate amounts of rare earth elements such as Y, Sc and Gd are added in aluminium alloy, the stress relaxation rate of the aluminium alloy can be reduced, the influence of residual stress in the aluminium alloy is reduced, and the high temperature heat stability and corrosion resistance of the aluminium alloy also can be improved. An aluminium alloy refrigerator foaming mould casting processed by adopting the processing technology disclosed by the invention has the advantages of good mechanical properties, high strength, good heat resisting property, good usability, good internal structure compactness, no pore or peeling, high abrasion resistance, high oxidation resistance, low expansion coefficient and the like.

Description

The complete processing of high-performance aluminium alloy foaming mould foundry goods

Technical field

The complete processing that the present invention relates to a kind of high-performance aluminium alloy foaming mould foundry goods, belongs to aluminum alloy materials processing technique field.

Background technology

?an important mould of the manufacture that refrigerator foaming mould is produced as refrigerator, the quality of its processing and manufacturing, will be directly connected to the quality of whole product, even can affect the success or failure that whole product is manufactured.The material that can be used as at present refrigerator foaming mould has metal and nonmetal two classes, and the foaming mould that adopts metal to manufacture can apply in enormous quantities and high-speed production undoubtedly, and foaming mould metallic substance has aluminium, copper, low melting point alloy, nickel, iron, zinc alloy etc.The foaming mould that wherein aluminium alloy is manufactured is most widely used general, and it has good heat conductivity, easily regulates die temperature, be difficult for getting rusty and being corroded, easily maintenance, keeping, cheap, manufacture the advantages such as time period.But aluminium alloy foaming mould also exists the shortcomings such as matter is soft, intensity is low, dense internal organization is poor, therefore, be badly in need of a kind of high performance aluminium alloy refrigerator foaming mould of research and development.

Summary of the invention

The object of the invention is to for the deficiencies in the prior art, a kind of complete processing of high-performance aluminium alloy foaming mould foundry goods is provided, improve the over-all properties of aluminium alloy refrigerator foaming mould.

The technical solution used in the present invention is as follows:

The complete processing of high-performance aluminium alloy foaming mould foundry goods, comprises the following steps:

(1) batching

Meet following requirement according to element mass percent: Si≤0.5%, Fe≤0.4%, Cu≤0.2%, Mn 0.60-1.2%, Mg 4.5-5.6%, Cr 0.15-0.25%, Zn≤0.25%, Ti≤0.15%, Y 0.05-0.08%, Sc 0.04-0.06%, Gd 0.02-0.03%, other impurity elements add up to≤0.15%, all the other are Al, prepare burden;

(2) melting

Batching is dropped into successively and in smelting furnace, carries out melting, in stove, be controlled at 720-750 DEG C, feed intake after 30-50min, there is aluminium water in stove time, add insulating covering agent to cover, start stir, after adjusting component, add refining agent through refining, skimming obtains after qualified composition, aluminium liquid is injected to holding furnace from smelting furnace, furnace temperature leaves standstill and keeps 20-30min under 715-740 DEG C of condition, then utilizes argon gas to take the hydrogen in aluminium liquid and fine impurities to surface, thereby reduces the hydrogen richness in aluminium liquid;

(3) casting

Aluminium liquid enters crystallizer by the relief hole of smelting furnace through aluminium groove, casts out needed foundry goods, and casting temp is controlled at 680-720 DEG C, casting speed control 32-45mm/min, and cooling water flow is controlled at 1050-1250 l/min;

(4) thermal treatment

Foundry goods is carried out after surface treatment, carry out homogenizing annealing processing, detailed process is as follows: be first warming up at 305-320 DEG C, insulation 2-3h, a 70-90 per hour DEG C intensification is heated to be incubated 6-8h at 540-560 DEG C, then air cooling, then a 60-80 per hour DEG C intensification is heated to 350-370 DEG C, and degree of insulation 5-6h; Be cooled at 160-180 DEG C again and be incubated 3-4h, air cooling is to room temperature.

Described insulating covering agent is the mixture of the soda of 40-50% and the fluorite of 50-60% composition; Described refining agent is made by following raw materials in part by weight: Repone K 5-8, barium fluoride 3-5, sodium-chlor 3-5, Graphite Powder 99 5-8, NaBF ₄8-10, magnesium oxide 5-8, vermiculite 8-10, trees ash 5-8, Na ₂tiF ₆8-10, barium sulfate 5-8;

Described refining agent preparation method is as follows:

A, by 10-15% salt acid soak 3-4 hour for the vermiculite of above-mentioned weight part, deionized water wash, then soak 3-4 hour with 10-12% sodium hydroxide solution, then with deionized water wash to neutral, then at 500-530 DEG C, calcine 2-3 hour, be ground into nanometer powder;

B, by after the each heating raw materials melting beyond vermiculite, clarification 1-2 hour, is poured into water cold quenching by clear liquor above, obtains broken particle;

C, the mixing of materials that step a, b are obtained stir and obtain described refining agent.

Beneficial effect of the present invention:

In aluminium alloy of the present invention, add appropriate rare earth element y, Sc, Gd, can fall low-alloyed stress relaxation rate, reduced the impact of the unrelieved stress in alloy, also can put forward heavy alloyed high high-temp stability, erosion resistance.The aluminium alloy refrigerator foaming die casting that the present invention processes has good mechanical property, intensity is high, and good heat resistance, workability are good, and dense internal organization is good, there is not pore and peeling defect, wear resistance is good, corrosion resistance, good in oxidation resistance, the advantage such as the coefficient of expansion is little.

embodiment

The complete processing of high-performance aluminium alloy foaming mould foundry goods, comprises the following steps:

(1) batching

Meet following requirement according to element mass percent: Si≤0.5%, Fe≤0.4%, Cu≤0.2%, Mn 0.60-1.2%, Mg 4.5-5.6%, Cr 0.15-0.25%, Zn≤0.25%, Ti≤0.15%, Y 0.05-0.08%, Sc 0.04-0.06%, Gd 0.02-0.03%, other impurity elements add up to≤0.15%, all the other are Al, prepare burden;

(2) melting

Batching is dropped into successively and in smelting furnace, carries out melting, in stove, be controlled at 740 DEG C, feed intake after 45min, there is aluminium water in stove time, add insulating covering agent to cover, start stir, after adjusting component, add refining agent through refining, skimming obtains after qualified composition, aluminium liquid is injected to holding furnace from smelting furnace, furnace temperature leaves standstill and keeps 30min under 720 DEG C of conditions, then utilizes argon gas to take the hydrogen in aluminium liquid and fine impurities to surface, thereby reduces the hydrogen richness in aluminium liquid;

(3) casting

Aluminium liquid enters crystallizer by the relief hole of smelting furnace through aluminium groove, casts out needed foundry goods, and casting temp is controlled at 695 DEG C, casting speed control 38mm/min, and cooling water flow is controlled at 1100 l/min;

(4) thermal treatment

Foundry goods is carried out, after surface treatment, carrying out homogenizing annealing processing, and detailed process is as follows: be first warming up at 310 DEG C, insulation 3h, 75 DEG C of intensifications per hour are heated to be incubated 8h at 550 DEG C, then air cooling, 80 DEG C of intensifications per hour are heated to 360 DEG C again, and degree of insulation 6h; Be cooled at 160 DEG C again and be incubated 3h, air cooling is to room temperature.

The mixture of the soda that wherein, described insulating covering agent is 50% and 50% fluorite composition; Described refining agent is made by following raw materials in part by weight: 8 parts, Repone K, 5 parts of barium fluorides, 4 parts, sodium-chlor, 7 parts of Graphite Powder 99s, NaBF ₄9 parts, 8 parts, magnesium oxide, 10 parts of vermiculites, trees ash 8 parts, Na ₂tiF ₆8 parts, part, barium sulfate;

Described refining agent preparation method is as follows:

A, by 12% salt acid soak 4 hours for the vermiculite of above-mentioned weight part, deionized water wash, then soak 3 hours with 12% sodium hydroxide solution, then with deionized water wash to neutral, then calcining-3 hours at 515 DEG C, is ground into nanometer powder;

B, by after the each heating raw materials melting beyond vermiculite, clarify 1.5 hours, clear liquor is above poured into water to cold quenching, obtain broken particle;

C, the mixing of materials that step a, b are obtained stir and obtain described refining agent.

Through inspection, product chemical composition is: Si 0.342%, Fe 0.326%, Cu 0.087%, Mn 0.813%, Mg 5.436%, Cr 0.187%, Zn 0.186%, Ti 0.108%, Y 0.072%, Sc 0.055%, Gd 0.028%, and other impurity elements add up to 0.104%, all the other are Al; Mechanical property is: tensile strength 368Mpa, 0.2% yield strength 236Mpa, elongation 18%, Young's modulus 59Gpa.

Claims (1)

1. a complete processing for high-performance aluminium alloy foaming mould foundry goods, is characterized in that comprising the following steps:

(1) batching

Meet following requirement according to element mass percent: Si≤0.5%, Fe≤0.4%, Cu≤0.2%, Mn 0.60-1.2%, Mg 4.5-5.6%, Cr 0.15-0.25%, Zn≤0.25%, Ti≤0.15%, Y 0.05-0.08%, Sc 0.04-0.06%, Gd 0.02-0.03%, other impurity elements add up to≤0.15%, all the other are Al, prepare burden;

(2) melting

Batching is dropped into successively and in smelting furnace, carries out melting, in stove, be controlled at 720-750 DEG C, feed intake after 30-50min, there is aluminium water in stove time, add insulating covering agent to cover, start stir, after adjusting component, add refining agent through refining, skimming obtains after qualified composition, aluminium liquid is injected to holding furnace from smelting furnace, furnace temperature leaves standstill and keeps 20-30min under 715-740 DEG C of condition, then utilizes argon gas to take the hydrogen in aluminium liquid and fine impurities to surface, thereby reduces the hydrogen richness in aluminium liquid;

(3) casting

Aluminium liquid enters crystallizer by the relief hole of smelting furnace through aluminium groove, casts out needed foundry goods, and casting temp is controlled at 680-720 DEG C, casting speed control 32-45mm/min, and cooling water flow is controlled at 1050-1250 l/min;

(4) thermal treatment

Foundry goods is carried out after surface treatment, carry out homogenizing annealing processing, detailed process is as follows: be first warming up at 305-320 DEG C, insulation 2-3h, a 70-90 per hour DEG C intensification is heated to be incubated 6-8h at 540-560 DEG C, then air cooling, then a 60-80 per hour DEG C intensification is heated to 350-370 DEG C, and degree of insulation 5-6h; Be cooled at 160-180 DEG C again and be incubated 3-4h, air cooling is to room temperature;

Described insulating covering agent is the mixture of the soda of 40-50% and the fluorite of 50-60% composition; Described refining agent is made by following raw materials in part by weight: Repone K 5-8, barium fluoride 3-5, sodium-chlor 3-5, Graphite Powder 99 5-8, NaBF ₄8-10, magnesium oxide 5-8, vermiculite 8-10, trees ash 5-8, Na ₂tiF ₆8-10, barium sulfate 5-8;

Described refining agent preparation method is as follows:

A, by 10-15% salt acid soak 3-4 hour for the vermiculite of above-mentioned weight part, deionized water wash, then soak 3-4 hour with 10-12% sodium hydroxide solution, then with deionized water wash to neutral, then at 500-530 DEG C, calcine 2-3 hour, be ground into nanometer powder;

B, by after the each heating raw materials melting beyond vermiculite, clarification 1-2 hour, is poured into water cold quenching by clear liquor above, obtains broken particle;

C, the mixing of materials that step a, b are obtained stir and obtain described refining agent.