plastics and plastic molding industry

the quality of the plastic molds are increasingly high requirements, and thus the failure of plastic mold problem and its influencing factors has become an important research topic. The main paper disc  working parts of the plastic molded parts, such as punch, die, etc., which constitute the plastic mold cavity to a variety of molded plastic parts and direct contact with the plastic surface, subjected to pressure, temperature, friction and corrosion effect.
2, plastic materials failure analysis
General mold manufacturing including mold design, selection of materials, heat treatment, machining, commissioning and installation process. According to the survey showed that: die failure factors, the mold material used and the heat treatment is a major factor affecting the service life. From the perspective of total quality management, can not affect the abrasive sanding belt  die life as a polynomial of the various factors and to measure, but should be the product of many factors, so that the merits of mold material and heat treatment process in the whole mold is particularly important.
A common phenomenon from die failure analysis, plastic mold in the service process, can produce wear failure, localized deformation failure and fracture failure. Plastic mold of the important failure modes can be divided into wear failure, failure of local plastic deformation and fracture failure.
3, plastic mold steel performance requirements with the rapid development of manufacturing, plastic mold plastic molding an indispensable tool in the overall proportion of mold production increased year by year, with the development of high-performance plastics and continuous production, types of plastics, increasing use of expanding products to precision, large-scale, complex development. Molding production to high-speed development, mold working conditions are also increasingly complex.
1) Wear and corrosion of the surface of the cavity
Plastic melt with a certain pressure in the mold cavity flow, solidification of the plastic parts from the mold, the  sanding belt molded surface of the mold are caused by friction and cause wear. Plastic mold caused by wear failure is the root cause of friction between the mold and the material. However, the specific form and abrasion wear process is related to many factors, such as mold in the course of the pressure, temperature, material strain rate and lubrication conditions. When the plastic material and heat treatment mold used is unreasonable, the plastic mold cavity to a low surface hardness, wear resistance is poor, and its performance: the cavity surface and deformation due to wear caused by the size tolerance; roughness becomes higher due to galling , surface quality is deteriorated. Especially when using solid plastic material into the mold cavity, it will aggravate the wear of the cavity surface. When combined with plastic processing contain chlorine, fluorine and other ingredients thermal decomposition corrosive gases HC1, HF, produce the plastic mold cavity surface corrosion and wear, resulting in failure. If you wear while there wear damage, the cavity surface coating or other protective layer destruction, it will promote the corrosion process. Two kinds of damage cross role in accelerating the corrosion a wear failure.