Traditional heat treatment for die-casting molds involves quenching and tempering, followed by surface treatment technologies. Because a wide variety of materials can be used for die-casting molds, the same surface treatment techniques and processes can produce different results on different materials. Schoff proposed a substrate pretreatment technology that addresses both the mold substrate and surface treatment techniques. Building upon traditional processes, this technology proposes suitable processing methods for different mold materials, thereby improving mold performance and extending mold life. Another direction for improving heat treatment technology is to combine traditional heat treatment processes with advanced surface treatment processes to further extend the service life of die-casting molds. For example, combining carbonitriding, a chemical heat treatment method, with conventional quenching and tempering processes to achieve NQN (carbonitriding-quenching-carbonitriding composite strengthening) not only results in higher surface hardness but also increases the effective hardened layer depth, optimizes the hardness gradient distribution of the diffused layer, and improves tempering stability and corrosion resistance. This allows die-casting molds to achieve excellent core performance while significantly improving surface quality and overall performance.
Die-casting molds are a major category of molds. With the rapid development of my country's automotive and motorcycle industries, the die-casting industry has entered a new era of development, simultaneously placing higher demands on the comprehensive mechanical properties and lifespan of die-casting molds. Luo Baihui, Secretary-General of the International Mold Association, believes... To meet the ever-increasing performance demands, relying solely on new mold materials is insufficient. Various surface treatment technologies must be applied to the surface treatment of die-casting molds to achieve the required high efficiency, high precision, and long service life. Among various molds, die-casting molds operate under the most demanding conditions. Pressure casting involves filling the mold cavity with molten metal under high pressure and high speed to form the mold shape. During operation, the mold repeatedly comes into contact with incandescent metal, thus requiring high resistance to thermal fatigue, thermal conductivity, wear resistance, corrosion resistance, impact toughness, red hardness, and good demolding properties. Therefore, the surface treatment technology for die-casting molds has high requirements.
