There are many factors that affect the quality of die-c […]
There are many factors that affect the quality of die-casting parts, such as the type and quality of die-casting machines, the rationality of the geometric structure and technical requirements of die-casting parts, the structure of the mold and the technical level of the operators.
1. Design of die casting
The designer should first fully understand the user's use requirements and working conditions, and the stress of the die-casting parts, and then select the appropriate material according to the use requirements and working environment, and understand its die-casting performance. When designing, pay special attention to keeping the die casting structure as simple as possible under the premise of meeting the requirements of use. The wall thickness is appropriate and uniform, and the necessary draft angle is left, otherwise it will cause pits, pores, shrinkage, under-casting, pull marks, cracks, deformation and other defects on the die casting.
The dimensional accuracy requirements of die castings should be reasonable, otherwise it will cause unnecessary troubles for mold design, mold processing, formulation and management of process conditions, and a large number of substandard products.
2. Mold structure, processing accuracy and selection of mold materials
Die-casting parts are die-casted by molds. There is no doubt that mold design, processing, and mold material selection are closely related to product quality. The mold structure is unreasonable, no matter what measures are taken from the process, it is difficult to make the product qualified.
In addition, mold materials, mold processing accuracy, surface roughness, processing traces, small cracks in heat treatment, nitride layer thickness and improper mold assembly, etc., will affect the quality of the product and the life of the mold.
3. Shrinkage rate of casting material
When the shrinkage rate of the casting material is generally given in the form of an average percentage or a percentage with a certain range of variation, the average shrinkage rate of the material is usually selected. For high-precision die-casting parts, special attention should be paid to the material shrinkage when designing molds. If necessary, test molds can be made first. After obtaining the required data on the test molds, the design and manufacture of molds for mass production can be started.
4. Formulation and implementation of die casting process
The formulation and execution of the die-casting process is related to the quality of the mold, die-casting equipment, and the technical level of the operators. Under the conditions of existing domestic die-casting equipment, it is difficult to achieve stable, reliable and precise control of die-casting process parameters. Realizing the basic control of the die-casting process is a process of combining and applying elements such as die-casting equipment, die-casting materials and molds. Lax implementation of the process and main parameters will cause shrinkage, deformation, under-casting, and unqualified dimensions of the die-casting parts.