There are numerous factors influencing die casting failure, including external elements such as casting temperature, whether the mold is preheated, the amount of water-based paint spray, the tonnage match of the die casting machine, and excessive pressure. Additionally, there are internal reasons like the metallurgical quality of the mold material, the forging process of the billet, and the rationality of the mold structure design. The editor of the aluminum die casting factory will analyze these factors from both internal and external perspectives.

If a mold experiences early failure, it is necessary to identify the internal or external factors at play to improve upon future designs. However, in actual production, erosion is typically localized to specific areas of the mold, such as the parts directly impacted by the inner gating (core, cavity), which are prone to erosion, as well as softer areas that are more susceptible to aluminum alloy sticking.

Under the action of the pressing force, die casting molds may develop cracks at weak points, particularly at the marked lines or electrical machining marks on the mold forming surface that have not been polished smooth, or at the sharp corners of the formed parts. When there are brittle phases at the grain boundaries or the grains are coarse, it becomes easier for the mold to fracture. Moreover, during brittle fracture, the crack propagation is rapid, which poses a dangerous factor for the mold's cracking failure. To address this, it is essential that all scratches and electrical machining marks on the mold surface be polished smooth, even if they are located in the gating system. Additionally, the mold material used must have high strength, good plasticity, and excellent impact and fracture toughness.

Common die-casting alloys used in erosion failure include zinc alloys, aluminum alloys, magnesium alloys, and copper alloys, as well as pure aluminum die-casting. Zn, Al, and Mg are lively metal elements that have good affinity with mold materials, especially Al which is prone to sticking to the mold. When the mold hardness is high, its corrosion resistance is better, but if there are soft spots on the formed surface, it is unfavorable for corrosion resistance.

During the die casting process, the repeated effects of intense cooling and heating on the die mold lead to deformation of the surface and internal structure, resulting in cyclic thermal stresses. This causes structural damage and loss of resilience, triggering the appearance of microcracks that continue to expand. Once the cracks propagate, molten metal can also infiltrate, along with repeated mechanical stresses, accelerating the expansion of the cracks.