Casting method of ZL101 thin-wall aluminium alloy part

Abstract

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.

Description

technical field [0001] The invention relates to the technical field of aluminum alloy casting, in particular to a casting method of a thin-walled aluminum alloy casting. Background technique [0002] At present, more and more thin-walled aluminum alloy parts are formed by one-time casting, such as large seat, volute, and hatch castings. These castings are large in size, thin in wall, and have many unprocessed surfaces. The wall thickness is 40- 100mm, the wall thickness is 3-5mm, the wall thickness transition is uneven, the casting process is difficult, and the size is difficult to control. This type of casting usually adopts ZL101 alloy sand gravity casting or metallic die casting. Although ZL101 alloy has good fluidity, but The cooling speed of liquid metal in thin-walled, narrow and long channels is fast, and casting defects such as cold shuts are prone to occur. In the prior art, methods such as runner design, cold iron arrangement, and riser design are usually used to i...

AI Technical Summary

Problems solved by technology

[0005] The original sand and binder type in the molding sand have an important impact on the performance of the casting, especially for aluminum alloy casting. The sand particle size in the traditional aluminum alloy casting sand formula is too large or too small, and the material diameter of the molding sand Too large, although the air permeability is good, but the surface of the aluminum sand parts is rough, the finish is not good, the diameter of the sand material is too small, resulting in poor air permeability of the sand mold, and the aluminum castings have pores

Coal powder clay green sand, which is widely used at home and abroad, is generally made of raw sand, binders, coal powder additives, etc. and water. It has a certain anti-sticking sand effect, low material cost, and high production efficiency. However, its consumption is large, the emission is serious, and the coal powder is burned and decomposed in the casting process to produce toxic gas pollution.

In addition, the traditional sand casting aluminum alloy products have a defect rate of more than 15% such as sand sticking, pores, and cracks, and the high rejection rate leads to a great increase in the cost of castings.