CN103014456B - Processing method of corrosion-resisting aluminum alloy foaming die cast - Google Patents

Abstract

The invention discloses a processing method of an corrosion-resisting aluminum alloy foaming die cast. The processing method comprises the five steps of compounding, smelting, pouring, thermal treatment, and extrusion forming. According to the invention, an appropriate amount of rare earth elements La, Er and Gd are added to the aluminum alloy, and effective microalloying action can occur between the rare earth elements and the alloy, thus improving the stress-corrosion-resisting property and the strength property of the alloy. The processed aluminum alloy refrigerator foaming mold die cast has the advantages of good mechanical properties, high strength, good usability, good internal structure compactness, no pore and peeling defects, good wear resistance, good corrosion resistance and oxidation resistance, small expansion coefficient and the like.

Description

The complete processing of anticorrosion aluminium foaming mould foundry goods

Technical field

The complete processing that the present invention relates to a kind of anticorrosion aluminium 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 anticorrosion aluminium 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:

(1) batching

Meet following requirement according to element mass percent: Si≤0.15%, Fe≤0.25%, Cu 2.4-2.8%, Mn≤0.2%, Mg 1.8-2.5%, Cr≤0.05%, Zn 5.5-6.5%, Ti≤0.06%, Zr 0.08-0.15%, La 0.04-0.06%, Er 0.05-0.08%, Gd 0.02-0.04%, 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 695-760 ℃, feed intake after 40-60min, 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 710-740 ℃ 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 690-725 ℃, casting speed control 32-45mm/min, and cooling water flow is controlled at 950-1150 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 ℃, insulation 2-3h, a 70-90 per hour ℃ intensification is heated to be incubated 6-8h at 530-560 ℃, then air cooling, then a 60-80 per hour ℃ intensification is heated to 350-370 ℃, and degree of insulation 5-6h; Be cooled at 160-180 ℃ again and be incubated 3-4h, air cooling is to room temperature.

Described insulating covering agent is the mixture of the silicon-dioxide of 60-70% and the perlite of 30-40% composition; Described refining agent is made by following raw materials in part by weight: sodium-chlor 5-8, Calcium Fluoride (Fluorspan) 3-5, salt of wormwood 3-5, Graphite Powder 99 5-8, Sodium Silicofluoride 8-10, magnesium oxide 5-8, sepiolite 8-10, trees ash 5-8, NaBF ₄8-10, NaF 5-8;

Described refining agent preparation method is as follows:

A, by 10-15% salt acid soak 3-4 hour for the sepiolite 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 ℃, calcine 2-3 hour, be ground into nanometer powder;

B, by after the each heating raw materials melting beyond sepiolite, 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 elements La, Er, Gd, can effective Microalloying Effect occur with alloy, thereby put forward heavy alloyed anti-stress corrosion performance and strength property.The aluminium alloy refrigerator foaming mould cast that the present invention processes has good mechanical property, intensity high, and workability is 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

(1) batching

Meet following requirement according to element mass percent: Si≤0.15%, Fe≤0.25%, Cu 2.4-2.8%, Mn≤0.2%, Mg 1.8-2.5%, Cr≤0.05%, Zn 5.5-6.5%, Ti≤0.06%, Zr 0.08-0.15%, La 0.04-0.06%, Er 0.05-0.08%, Gd 0.02-0.04%, 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 725 ℃, feed intake after 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 30min under 730 ℃ 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 710 ℃, casting speed control 35mm/min, and cooling water flow is controlled at 1050 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 315 ℃, insulation 3h, 85 ℃ of intensifications per hour are heated to be incubated 7h at 540 ℃, then air cooling, 70 ℃ of intensifications per hour are heated to 360 ℃ again, and degree of insulation 5h; Be cooled at 170 ℃ again and be incubated 4h, air cooling is to room temperature.

The mixture of the silicon-dioxide that wherein, described insulating covering agent is 70% and 30% perlite composition; Described refining agent is made by following raw materials in part by weight: 7 parts, sodium-chlor, 4 parts, Calcium Fluoride (Fluorspan), 4 parts, salt of wormwood, 6 parts of Graphite Powder 99s, 9 parts of Sodium Silicofluorides, 6 parts, magnesium oxide, 9 parts of sepiolites, trees ash 8 parts, NaBF ₄8 parts of 9 parts, NaF;

Described refining agent preparation method is as follows:

A, by 12% salt acid soak 4 hours for the sepiolite of above-mentioned weight part, deionized water wash, then soak 4 hours with 10% sodium hydroxide solution, then with deionized water wash to neutral, then at 510 ℃, calcine 3 hours, be ground into nanometer powder;

B, by after the each heating raw materials melting beyond sepiolite, clarify-2 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 check, product chemical composition is: Si 0.112%, Fe 0.176%, Cu 2.645%, Mn 0.143%, Mg 2.412%, Cr 0.028%, Zn 6.257%, Ti 0.049%, Zr 0.092%, La 0.054%, Er 0.067%, Gd 0.033%, and other impurity elements add up to 0.131%, all the other are Al; Mechanical property is: tensile strength 487Mpa, 0.2% yield strength 431Mpa, elongation 12%, Young's modulus 68Gpa.

Claims (1)

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

(1) batching

Meet following requirement according to element mass percent: Si≤0.15%, Fe≤0.25%, Cu 2.4-2.8%, Mn≤0.2%, Mg 1.8-2.5%, Cr≤0.05%, Zn 5.5-6.5%, Ti≤0.06%, Zr 0.08-0.15%, La 0.04-0.06%, Er 0.05-0.08%, Gd 0.02-0.04%, 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 695-760 ℃, feed intake after 40-60min, 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 710-740 ℃ 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;

Described insulating covering agent is the mixture of the silicon-dioxide of 60-70% and the perlite of 30-40% composition;

Described refining agent is made by following raw materials in part by weight: sodium-chlor 5-8, Calcium Fluoride (Fluorspan) 3-5, salt of wormwood 3-5, Graphite Powder 99 5-8, Sodium Silicofluoride 8-10, magnesium oxide 5-8, sepiolite 8-10, trees ash 5-8, NaBF ₄8-10, NaF 5-8;

Described refining agent preparation method is as follows:

A, by 10-15% salt acid soak 3-4 hour for the sepiolite 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 ℃, calcine 2-3 hour, be ground into nanometer powder;

B, by after the each heating raw materials melting beyond sepiolite, 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;

(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 690-725 ℃, casting speed control 32-45mm/min, and cooling water flow is controlled at 950-1150 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 ℃, insulation 2-3h, a 70-90 per hour ℃ intensification is heated to be incubated 6-8h at 530-560 ℃, then air cooling, then a 60-80 per hour ℃ intensification is heated to 350-370 ℃, and degree of insulation 5-6h; Be cooled at 160-180 ℃ again and be incubated 3-4h, air cooling is to room temperature.