The die-casting mold is a method of casting liquid die […]
The die-casting mold is a method of casting liquid die forging, a process performed on a dedicated die-casting die forging machine. The basic process is: the metal liquid is first filled into the cavity of the mold by low speed or high speed casting, and the mold has a movable cavity surface, which is pressed and forged with the cooling process of the molten metal, thereby eliminating the shrinkage of the blank. The loose defect also causes the internal structure of the blank to reach the forged broken grain. The overall mechanical properties of the blank are significantly improved.
Die-casting materials, die-casting machines and molds are the three major elements of die-casting production, and they are indispensable. The so-called die-casting process is to combine these three elements organically, so as to enable stable, rhythmic and efficient production of qualified castings with good appearance, good internal quality, dimensional conforming to drawings or agreements, and even high-quality castings.  .
The alloys used in die castings are mainly non-ferrous alloys, and ferrous metals (steel, iron, etc.) are less used due to problems such as mold materials. Among the non-ferrous alloy die-casting parts, aluminum alloy is widely used, and zinc alloy is second. The following is a brief introduction to the case of die-casting non-ferrous metals.
(1) Classification of die-casting non-ferrous alloys, shrinkage, shrinkage, shrinkage, shrinkage, free shrinkage, lead alloy-----0.2-0.3%, 0.3-0.4%, 0.4-0.5%, low-melting alloy, tin alloy, zinc alloy--------0.3 -0.4% 0.4-0.6% 0.6-0.8% Aluminum-silicon--0.3-0.5% 0.5-0.7% 0.7-0.9% Die-casting non-ferrous alloy aluminum alloy copper-based aluminum-magnesium---0.5-0.7% 0.7-0.9% 0.9-1.1% High melting point alloy aluminum-zinc-based magnesium alloy----------0.5-0.7% 0.7-0.9% 0.9-1.1% copper alloy
(2) Recommended casting temperature for various die-casting alloys Alloy type Average wall thickness of castings ≤ 3mm Average wall thickness of castings > 3mm Simple structure Complex structure Simple structure Complex
Aluminum alloy Aluminum silicon 610-650°C 640-680°C 600-620°C 610-650°C
Aluminum and copper 630-660°C 660-700°C 600-640°C 630-660°C
Aluminum-magnesium 640-680°C 660-700°C 640-670°C 650-690°C
Aluminum zinc system 590-620°C 620-660°C 580-620°C 600-650°C
Zinc alloy 420-440°C 430-450°C 400-420°C 420-440°C
Magnesium alloy 640-680°C 660-700°C 640-670°C 650-690°C
Copper alloy Ordinary brass 910-930°C 940-980°C 900-930°C 900-950°C
Silicon Brass 900-920°C 930-970°C 910-940°C 910-940°C
* Note: 1 The casting temperature is generally measured by the temperature of the molten metal in the holding furnace.
2 The casting temperature of the zinc alloy should not exceed 450 ° C to avoid coarse grains.