Abrasives some simple narrative

 failure of the plastic deformation
Plastic mold cavity surface pressure, heat can cause plastic deformation failure, especially when small mold equipment when working on large-tonnage, more prone to overload plastic deformation. Plastic mold materials used in insufficient strength and toughness, low deformation resistance; another reason for failure of the plastic deformation is mainly the mold cavity surface of the hardened layer is too thin, the deformation resistance is insufficient or the tempering temperature is higher than the softening temperature of the phase change , leaving the mold early failure.
 Fracture
The main reason is due to structural faults, temperature and the resulting structural stress, thermal stress, or because of insufficient tempering, at the temperature, the residual austenite into martensite, causing local volume expansion, generated in the mold organization Stress due.
Plastic mold Die different working conditions, generally at 150 ℃ -200 ℃ shall work under pressure in addition to being a certain role, but also to withstand temperature. There will be a variety of the same kind of mold failure modes, even in the same mold may also be a variety of injuries. Known from failure mode of plastic, a reasonable selection of plastic mold material and heat treatment is very important, since they are directly related to the life of the mold. So, plastic mold steel should meet the following requirements:
A) heat resistance
With the emergence of high-speed molding machinery, plastic products run faster. As mold temperature at 200 - 350 ℃ between, if  abrasive wheel the plastic flowability is fast forming speed, molding mold part will very soon overtake the surface temperature 400 ℃. In order to ensure the accuracy of the mold and the use of a slight deformation of the mold should have a higher heat resistance steel.
 sufficient abrasion resistance
With the expanded use of plastic, the plastic is often required to add an inorganic glass fiber reinforced plastic materials, as additives added to the plastic flow is greatly reduced, resulting in wear of mold only, the game requires a good wear resistance.
excellent machinability
Most plastic mold, unless needed for some EDM machining and fitter repair. To extend the service life of the cutting tool, the cutting of small hardening process. To prevent mold deformation affect the accuracy and hope machining residual stress can be controlled to a minimum.
good thermal stability
Plastic injection mold tend to be more complex shape parts after quenching difficult to process, so should be PSA sanding disc  used with a good thermal stability of the material after heat treatment when the molding die due to thermal expansion coefficient, heat deformation, due to differences in the size of the temperature the rate of change is small, stable microstructure and die size can be reduced or no longer working, you can ensure that the mold dimensional accuracy and surface roughness.
Mirror processing performance
Cavity surface is smooth, polished to a mirror surface requires molding, the surface roughness is less than Ra0.4μm, to ensure that the appearance of the plastic moldings and facilitate release.
 Heat treatment performance
In die failure accidents, accidents caused due to the heat treatment is generally 52.3%, resulting in the entire heat treatment mold manufacturing process occupies an important position, the metal cutting wheel  quality of heat treatment on the quality of the mold have a greater impact. General requirements for heat deformation small, quenching temperature range, thermal sensitivity is small, especially to have a greater hardenability and hardenability and so on.
Corrosion resistance
During the forming process may emit corrosive gas thermal decomposition corrosive gases such as HC1, HF and other corrosive mold, sometimes in the air stream crossing at the mold corrosion and damage, and called die steel has good corrosion resistance.
4, the new plastic mold steel
General plastic mold often used normalized 45 steel or 40Cr quenched and tempered steel manufacturing. Require a higher hardness of the plastic mold using CrWMn or Crl2MoV other steel manufacturers. For higher operating temperature of the plastic mold, you can choose to use high toughness hot die steel. In order to meet the plastic cavity for dimensional accuracy and surface quality of the higher requirements, also recently developed a series of new die steel.