Currently, aluminum die casting molds are widely used in the mold industry due to their long production cycle, high investment and high precision, resulting in relatively high manufacturing costs. However, due to various internal and external factors such as materials and mechanical processing, the molds may fail prematurely and become scrapped. Below, we will analyze the reasons that affect the service life of aluminum die casting molds.
The selection of materials has a great impact on the service life of molds. According to data research, improper material selection and heat treatment may cause early failure of molds. Aluminum die casting molds belong to hot-working molds, and their production conditions are relatively harsh. The melting point of aluminum is between 580-740℃. Therefore, during the die casting process, the production personnel should control the temperature of aluminum liquid between 650-720℃ and preheat it. If not preheated, the temperature of the mold cavity surface will rise from room temperature to the liquid temperature, causing the surface to bear greater tensile stress. During the process of opening the mold components, the surface of the mold cavity will also bear great compressive stress, and after several thousand times of die casting, defects such as cracks will appear on the mold surface.
The aluminum die casting molds have a high requirement for material quality. At the current stage, the material for aluminum die casting molds is steel, which is a widely used hot-working mold steel. This kind of steel has excellent cold and hot fatigue resistance, fracture toughness and thermal stability. Before manufacturing aluminum die casting molds, the manufacturing personnel need to analyze and inspect the materials to prevent early scrapping of molds and waste of processing costs.
When designing aluminum die casting molds, sharp corners and large cross-sectional changes should be avoided, as stress concentration caused by sharp corners can be 10 times that of average stress in the mold, which can lead to early mold failure. In addition, designers should also pay attention to the subsequent heat treatment deformation and cracking of the mold. To prevent the above-mentioned defects, the cross-sectional dimensions of the mold should be evenly symmetrical, blind holes should be made into through holes as much as possible, and process holes can be made when necessary. Geometric notches such as notches, angles, grooves, holes and section mutations should be avoided in mold structure design.
Improper machining can lead to stress concentration and insufficient finish, which may cause defects in the mold and affect its service life. Therefore, during the mold processing, the surface of the cooling control system should be smooth and free of machining marks.
Above are the three main factors that affect the service life of aluminum die casting molds. With the advancement of science and technology, manufacturing personnel need to learn advanced machining techniques, pay attention to production matters, and try to improve the machining accuracy of aluminum die casting molds to extend their service life.