Die casting material, die casting machine and die are the three main elements of die casting production. The so-called die casting process is the organic comprehensive use of these three elements, so that the appearance, internal quality, size in line with the requirements of the drawing or agreement can be stable and efficient production of qualified castings, or even the process of high-quality castings
The alloys used in die casting are mainly non-ferrous alloys, and the ferrous metals (steel, iron, etc.) are less used due to the problems of die materials. In the non-ferrous alloy die casting, aluminum alloy is widely used, followed by zinc alloy. The following is a brief introduction to the situation of die-casting non-ferrous metals.
(1) the classification of die casting non-ferrous alloy is blocked mixed contraction free shrinkage lead alloy – 0.2-0.3-0.4-0.4% and 0.5% 0.3% low melting point alloy tin alloy zinc alloy — — — — — — — – 0.3-0.6-0.4-0.6% 0.4% and 0.8% Al-si series 0.7 0.5-0.3-0.5% – 0.7% – 0.9% of die casting non-ferrous alloy aluminum alloy aluminum bronze series aluminum magnesium – 0.5-0.7-0.9-0.9% and 1.1% 0.7% high melting point alloy aluminum zinc series magnesium alloys — — — — — — — — — – 0.5-0.7-0.9% 0.7%
(2) Recommended casting temperature for all types of die-casting alloys Average wall thickness of castings ≤3mm > 3mm Simple structure complex structure simple structure complex structure
Aluminum alloy aluminum silicon system 610-650℃ 640-680℃ 600-620℃ 610-650℃
Aluminum copper system 630-660℃ 660-700℃ 600-640℃ 630-660℃
Aluminum magnesium system 640-680℃ 660-700℃ 640-670℃ 650-690℃
Aluminum zinc system 590-620℃ 620-660℃ 580-620℃ 600-650℃
Zinc alloy 420-440℃ 430-450℃ 400-420℃ 420-440℃
Magnesium alloy 640-680℃ 660-700℃ 640-670℃ 650-690℃
Copper alloy common brass 910-930℃ 940-980℃ 900-930℃ 900-950℃
Silicon brass 900-920℃ 930-970℃ 910-940℃ 910-940℃
- Note: ① The casting temperature is generally measured by the temperature of the molten metal in the holding furnace.
② The casting temperature of zinc alloy should not exceed 450℃ to avoid coarse grain.
The design process
1.Conduct process analysis on the product according to the materials used in the product, the shape and precision of the product and other indicators, and work out the process.
2.Determine the position of the product in the mold cavity, analyze and design the parting surface, discharge system and pouring system.
3.Design the assembling and fixing methods of the core for each activity.
4.Design of core distance and force.
5.Design of ejection mechanism.
6.determine the die casting machine, die frame and cooling system design.
7.Check the relevant dimensions of molds and die casting machines, and draw the process drawings of molds and each part.