Die casting is an efficient metal casting process, which is widely used in industries such as automobiles, electronics, and medical devices. Accurate adjustment of control parameters is essential to ensure quality of die castings, improve production efficiency, and extend life of molds. Main die casting control parameters include temperature, pressure, speed, and time.
Key die casting control parameters
Temperature control: During die casting process, appropriate temperature control can ensure fluidity of aluminum liquid and reduce internal defects of castings. Pouring temperature of molten metal should be about 30℃ higher than liquidus temperature of alloy to compensate for heat loss during pouring process and ensure that molten metal has good fluidity when filling mold. Melting temperature of aluminum alloy is usually between 650℃-710℃, while mold temperature is between 150℃-250℃. Specific temperature depends on shape, structure, and wall thickness of casting. Thin-walled complex parts can use higher temperatures to improve fluidity, while thick-walled structural parts can use lower temperatures to reduce solidification shrinkage.
Pressure control: Proper pressure control can improve density and strength of aluminum alloys, thereby improving product quality. Pressure of aluminum alloy die casting is generally between 3500Psi and 4500Psi.
Speed control: In process of aluminum alloy die casting, length of processing time is also an important factor affecting product quality. By accurately controlling time and process of the entire casting process, accuracy and stability of product can be greatly improved.
Time control: Including filling time, holding time and cooling time, control of these times directly affects filling quality and internal structure of casting.

 

Extended reading: Necessity of preheating die casting molds
It is very important to preheat die casting mold. This step helps to improve quality of die castings, improve production efficiency and extend service life of mold. Here are a few key reasons for preheating:
Reduce thermal shock and thermal fatigue: Preheating can avoid thermal shock caused by high-temperature liquid metal to cold die casting mold, thereby reducing risk of mold failure due to premature thermal fatigue and extending service life of mold.
Improve filling and reduce defects: Preheating helps to maintain mold within a certain temperature range, avoid rapid loss of fluidity of liquid metal due to quenching, ensure that die casting can be filled smoothly, reduce defects such as insufficient pouring, cold shut, and freezing.
Adjust mold gap: Mold preheating can make gap part in mold properly adjusted through thermal expansion, prevent alloy liquid from passing through gap and affecting normal production.
Improve production efficiency and yield rate: Preheating mold can reduce hot mold time, speed up production progress, and keep temperature of mold stable during production process, thereby improving production efficiency and yield rate.
Control mold temperature: Preheating also helps to control mold temperature during die casting, avoiding premature condensation of metal due to too low temperature or mold expansion due to too high temperature, affecting accuracy and product quality.
Energy saving and environmental protection: Use of modern preheating equipment such as mold temperature controllers can achieve efficient heat transfer and circulation, reduce energy consumption, and reduce pollution to the environment.
In summary, preheating is a key step to ensure efficient and stable operation of die-casting molds. Preheating can significantly improve the overall performance and economic benefits of die-casting process.