Aluminum die-casting molds are a widely used type of mold. They feature long production cycles, high investment, and high precision, resulting in relatively high production costs. However, due to a range of internal and external factors, such as material quality and machining, molds can experience premature failure and become scrapped. Let's analyze what factors affect the service life of aluminum die-casting molds.

1. Materials

Mold material selection significantly impacts mold life. Research indicates that improper material selection and heat treatment can lead to premature mold failure. Aluminum die-casting molds are hot-working molds, subject to harsh manufacturing conditions. Aluminum's melting point is between 580°C and 740°C. Therefore, during die-casting, production personnel must maintain a molten aluminum temperature between 650°C and 720°C and preheat the mold. Failure to preheat the mold cavity surface will cause the temperature to rise from room temperature to liquid temperature, subjecting it to significant tensile stress. During the mold opening process, the cavity surface is also subject to significant compressive stress. After thousands of die-cast cycles, defects such as cracks may develop on the mold surface. In summary, aluminum die-casting molds require high material quality. Currently, aluminum die-casting molds are made of H13 steel, a widely used hot-working die steel with excellent thermal fatigue resistance, fracture toughness, and thermal stability.

Before manufacturing aluminum die-casting molds, manufacturers must analyze and inspect the materials to prevent premature mold failure and wasteful processing costs.

II. Structural Design

When designing aluminum die-casting molds, avoid overly sharp corners and large cross-sectional variations. These corners cause stress concentrations that are 10 times greater than the average mold stress, potentially leading to premature mold failure. Designers should also be aware of deformation and cracking during subsequent heat treatment. To prevent these defects, mold cross-sectional dimensions should be uniform and symmetrical. Blind holes should be opened as through holes as much as possible, and process holes can be added when necessary. The mold structure should also avoid geometric notches, including tool marks, angles, grooves, holes, and sudden cross-sectional changes.

3. Machining

Improper machining can easily lead to stress concentration and insufficient finish, potentially causing mold defects and shortening the mold's service life. Therefore, during mold machining, the surface of the cooling control system should be smooth and free of machining marks.

These are the three major factors that affect the service life of aluminum die-casting molds. With the advancement of science and technology, manufacturers need to learn advanced machining techniques, pay attention to production precautions, and strive to improve the machining accuracy of aluminum die-casting molds to extend their service life.