During the working process of aluminum alloy gravity casting, with the different degree of complexity of its casting shape, the casting molds of its products are also different. Even if the same part adopts different casting processes, the mold forms are often different. However, the aluminum alloy gravity casting molds still have their common features.
The proper casting process must be selected during the operation of gravity casting of aluminum alloy. The quality of the casting process is directly related to the quality of the casting and the yield of the process. Some domestic mold manufacturers have begun to use solidification simulation to carry out casting process aided design. Through the computer simulation of mold filling and solidification process, the hot junction parts prone to casting defects are found and overcome, which is very important and effective to improve the reliability of casting process design and effectively prevent unnecessary rework of molds during commissioning.
The mold should have good heat capacity. A thick mold base and module that meet the requirements is not only an effective guarantee for the life of the mold, but also plays a very important role in the adjustment of the temperature field in the continuous working process of the mold. The mold shall have reliable cooling system and air extraction system. By cooling, not only the labor productivity can be effectively improved, but also the casting temperature field can be adjusted and the casting cooling rate can be controlled, so as to affect the internal structure and grain size of the casting and realize the purpose of effectively controlling the mechanical properties of the casting. As the name suggests, air extraction is to artificially discharge the gas inside the mold cavity to the outside of the mold cavity to reduce the possibility of porosity defects in castings. At the same time, the mold temperature in local small area can also be adjusted by installing exhaust plug, which plays an important role in preventing and overcoming the cracking and shrinkage of aluminum alloy.
There must be a mold positioning device matching the casting machine and a convenient mold installation system. The positioning device is not only the key to ensure the size of the casting and reduce the cracks and burrs, but also the key to ensure the normal operation of the casting machine. It can be said that there is no good positioning device for the mold and no good qualified casting. The mold must be easy to install and disassemble. Because aluminum alloy > aluminum alloy gravity casting, the mold must be removed every certain time to spray paint and repair the mold. If the disassembly is not convenient, it will increase the labor intensity of workers, occupy more labor time, and reduce the output and efficiency.
