What are the main steps in manufacturing auto parts die casting?

1. Mold Preparation and Assembly
The pre-machined upper and lower mold halves are mounted on the auto parts die casting machine's pressure plate, ensuring a tight fit and locking in place.
To prevent metal sticking, a refractory coating is often sprayed onto the mold cavity surface or the surface is brushed clean.
2. Molten Metal Heating and Injection
The aluminum or magnesium alloy is heated to a suitable melting temperature (approximately 600–700°C) in a furnace, and then injected into the mold cavity at high speed and uniformly using a high-pressure injection system.
High-pressure injection can fill complex cavities in a very short time, ensuring uniform wall thickness.
3. Rapid Cooling and Solidification
After entering the mold cavity, the metal is immediately cooled rapidly by the mold's cooling system (usually water or oil cooling), forming a dense crystalline structure.
Rapid solidification is a key step in achieving fine wall thickness and high dimensional accuracy.
4. Mold Opening and Part Removal
After the metal has completely solidified, the mold is opened and the hot part is ejected using an ejector device.
After removal, necessary deburring, cleaning, and surface treatment are performed to meet subsequent assembly requirements.
How does die casting improve the strength and durability of auto parts? Mechanisms of Die Casting in Enhancing Strength and Durability
1. Fine Grain Structure
High-pressure injection and rapid cooling cause the alloy to form fine and uniform grains during solidification. Fine grains significantly improve the material's yield strength and fatigue life.
2. Excellent Surface Finish and Dimensional Accuracy
Die casting provides near-net-shape castings with low surface roughness and small dimensional errors, reducing stress concentration during subsequent machining and assembly, thereby improving overall durability.
3. Rational Rib and Reinforcing Rib Layout
During the mold design stage, optimizing rib shapes (such as hexagons and trapezoids) achieves uniform stress distribution, avoiding localized stress concentration that could lead to cracks or deformation. Good structural design directly enhances the part's impact resistance and fatigue resistance. 
4. Controlling Porosity and Defects
Through precise process parameters (injection speed, holding time, cooling rate) and a gas venting system, internal defects such as porosity and shrinkage cavities are minimized to ensure the density and reliability of the castings.