How to solve shell cracking in precision casting?

Precision casting is an irreplaceable process method in manufacturing high-precision and demanding parts. However, due to its complex manufacturing process, high equipment requirements, and high material requirements, it is inevitable to encounter some problems during the operation process, such as shell cracking. Shell cracking refers to a defect in the mold shell formed externally during the casting process of a workpiece, where some spontaneous cracks occur, resulting in partial or complete cracking of the casting. This article will mainly introduce how to solve the problem of shell cracking in precision casting molds from the following aspects.

1、 Choose appropriate casting materials

The occurrence of shell cracking is closely related to the strength and deformation ability of materials. In order to avoid the occurrence of shell cracking problems, it is necessary to choose suitable materials in precision casting, usually some more ductile materials, such as alloy casting materials, which have good ductility during deformation and crack propagation, and can greatly avoid material cracking.

2、 Optimize casting process parameters

Reasonable casting process parameters are the key to avoiding shell cracking problems. In the process of precision casting, it is necessary to reasonably control a series of process parameters such as core coils, liquid metal temperature, pouring speed, pouring pressure, etc. to ensure the smooth casting of parts. If these parameters are unreasonable, it can lead to defects in the parts, such as shell cracking. Therefore, optimizing casting process parameters is one of the important solutions. During the casting operation process, it is necessary to monitor and control various process parameters in real time, identify problems in a timely manner, and adjust them to ensure the stability and accuracy of the casting process.

3、 Adopting special casting process methods

Some castings with complex shapes may not be suitable using traditional casting techniques, which can easily cause uneven local stress on the parts and lead to shell cracking problems. In this case, some special casting processes can be used, such as wax injection method, cement mold casting method, vacuum casting method, etc. These process methods can effectively avoid the occurrence of shell cracking problems.

4、 Application of simulation technology

Nowadays, with the development of computer technology, casting simulation technology has been widely applied. This technology can conduct virtual experiments before product design, mold design, and casting process design, analyze and optimize process parameters, quickly evaluate the feasibility of design schemes, predict the occurrence of local quality defects and shell cracks, and effectively avoid unnecessary material waste and processing time loss. While applying simulation technology to precision casting, experimental data feedback can also be used to further optimize casting process parameters.

In summary, in precision castings, avoiding the occurrence of shell cracking requires multiple approaches. It is necessary to select suitable materials, optimize casting process parameters, adopt special casting process methods, and apply simulation techniques. Only through continuous technological improvement and practical exploration can we ensure the quality of products and the progress of casting processes.