Some common sense of die casting, die casting processing manufacturers to solve your confusion
Die-casting processing manufacturers believe that in the design of die-casting molds, many problems need to be solved, such as the direction selection of moving molds and fixed molds, the selection of parting surfaces, the design of the pouring system, the determination of the core pulling slider, and the arrangement of the ejector rod. Among them, the gating system is an unpredictable factor, which is a decisive factor for the quality of the casting, and it is also very difficult to design. The gating system is well designed and the product qualification rate is high; The gating system is poorly designed, the product qualification rate is low, and even the mold is scrapped. Therefore, it is important to strengthen the research on the design of the gating system.
Die-casting processing manufacturers believe that die-casting is neither gravity casting nor anti-gravity casting, but high-speed and high-pressure forced injection. The area of the inner gate is a fraction of the area of the injection punch, and the injection speed of the molten aluminum is several times that of the punch. Therefore, the spray speed of the inner door generally reaches tens or even hundreds of meters per second, far exceeding the general fire hydrant's rate of fire of 25m per second, and the water filling time is only tens of milliseconds to hundreds of milliseconds. The cavity is mainly exhausted by the parting surface, and the gas in the cavity is difficult to discharge, and the casting pores are serious.
Die-casting processing manufacturers believe that the working surface of the die-casting mold is in direct contact with liquid metal, and it is subject to the erosion and heating of high-pressure and high-speed flowing liquid metal. After the workpiece is demolded, it cools down quickly. Therefore, thermal fatigue cracking, thermal wear and hot melt erosion are common failure forms of die casting molds. Therefore, die-casting molds are required to have cold and hot fatigue resistance, high temperature strength and toughness, liquid metal erosion resistance, high heat resistance, high thermal conductivity, good oxidation resistance and high hardenability.
Die-casting processing manufacturers believe that the heat treatment process is widely used in die-casting mold manufacturing, which can improve the performance of mold parts and extend the service life of the mold. In addition, heat treatment can also improve the processing performance of die-casting molds, improve processing quality, and reduce tool wear, so it plays a very important role in mold manufacturing. Die-casting molds are mainly made of steel, and the conventional heat treatment in their manufacturing process includes spheroidizing annealing, stabilization treatment, quenching and tempering, quenching and tempering. Through these heat treatment processes, the microstructure of the steel is changed, so that the desired structure and properties of the die-casting mold are obtained.
1. Preprocessing. Die-casting processing manufacturers believe that after the blanks of die-casting molds are forged, spheroidization annealing or tempering heat treatment must be used. On the one hand, it can relieve stress, reduce hardness, facilitate cutting, and at the same time can prepare for heat treatment. After annealing, uniform microstructure and diffused carbides can be obtained, which improves the strength and toughness of the mold steel. Because the effect of quenching and tempering is better than that of spheroidization annealing, quenching and tempering is often used instead of spheroidizing annealing for molds with higher requirements for strength and toughness.
2. Stabilization treatment. Die-casting processing manufacturers believe that in general, the cavity of the die-casting mold is complex, which will produce large internal stress during rough machining and deformation during quenching. In order to relieve stress, stress relief annealing, that is, stabilization treatment, should usually be carried out after rough machining.
3. Quenching and preheating. Die-casting processing manufacturers believe that most of the die-casting steels are high-alloy steels. Due to their poor thermal conductivity, quenching and heating must be carried out slowly, and preheating measures are often taken. For molds with low anti-deformation requirements, the number of preheating times can be less and not cracked, but the mold with high anti-deformation requirements must be preheated many times. Preheating at lower temperatures is generally carried out in an air furnace; When the temperature is high, the salt bath furnace should be used to preheat, and the preheating time is still calculated as 1min/mm.
4. Quenching and heating. Die-casting processing manufacturers believe that for typical die-casting mold steel, higher quenching heating temperature is conducive to improving thermal stability and softening resistance, reducing thermal fatigue tendency, but will cause grain growth and grain boundary carbide formation, reduce toughness and plasticity, and lead to serious cracking. Therefore, when the die-casting mold requires high toughness, low-temperature quenching is often used, and when high-temperature strength is required, higher temperature quenching is used.
In order to make the company more competitive, it invested 20 million yuan in 2010 and 5 million yuan in 2018 to add die-casting machines, X-ray flaw detection equipment, spectral analysis equipment and various product performance testing equipment, so that the quality of products can be effectively controlled. The company has passed ISO9001-2015 certification, in order to meet the needs of customers. Adhering to the enterprise tenet of "pursuing good quality and timely service", our company constantly promises and serves customers with perfect service and scientific management, and creates a better tomorrow with you!
The company is located in the scenic Yangcheng Lake in Xiangcheng District, Suzhou, bordered by Shanghai-Nanjing Expressway in the north and Sujiahang Expressway in the east, with convenient transportation. Founded in 1993, the company is mainly engaged in the manufacturing, sales and service of drum washing machine bracket shaft, tripod, pulley, door hinge, door hook, cross, wind impeller, bearing seat, etc.
Suzhou Yueerhan Machinery Technology Co., Ltd. was established in 1993, the company is located in the scenic Yangcheng Lake in Suzhou Xiangcheng District, north of Shanghai-Nanjing Expressway, east of Sujiahang Expressway, convenient transportation.
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