Email Us

Material Requirements for Injection Mold Standard Parts

The design and manufacture of molds is an important issue in the selection of mold materials, and it directly affects the service life of molds, mold manufacturing processes, mold processing costs, and the quality of plastic parts.


In order to extend the service life of molds, a lot of research and engineering practice has been carried out on the surface enhancement treatment of mold forming parts, and good results have been achieved. The working conditions of plastic standard mould parts are affected by both temperature and pressure, and they generally work at 150-200℃. The basic performance requirements of steel for plastic molding molds are summarized as follows:


Sufficient surface hardness and wear resistance of injection mold standard parts


After heat treatment, the mold should have sufficient surface hardness. The hardness of plastic molds is usually below 50-60HRC to ensure sufficient rigidity. Molds must withstand high compressive stress and frictional stress, and due to the filling and flow of plastics, this requires stable dimensional accuracy and shape accuracy of molds to ensure sufficient service life of the molds. Increasing the hardness of molds is beneficial to improving their wear resistance.


Good machining performance of injection mold standard parts


Steel grades that are easy to cut and can obtain high-precision parts after processing should be selected. Therefore, medium carbon steel and medium carbon alloy steel are most commonly used. This is particularly important for large molds. For parts that require electric discharge machining, the burn hardening layer of the steel should be thin.


Excellent polishing performance of injection mold standard parts


High-quality plastic products require a small cavity surface roughness. Therefore, the working surface of injection standard mould parts needs to be polished into a mirror finish. If the surface is too hard, polishing is difficult. Therefore, the selected steel should have a uniform and dense microstructure, low impurities, no fiber directionality, and no defects such as pitting or orange peel during polishing.


Good thermal stability of injection mold standard parts


Plastic injection molds should select materials with good thermal stability as much as possible, because the parts are often complex in shape and difficult to machine after quenching. In order to ensure the dimensional accuracy and surface roughness requirements of the molds, the deformation after heat treatment should be small, the size change rate caused by temperature difference should be small, the molding piece linear expansion coefficient should be small, the metallographic structure and mold size should be stable, which can reduce or stop processing.


Good wear resistance and fatigue resistance of injection mold standard parts


The cavity of injection mould base parts is not only affected by the high-pressure plastic melt flushing, but also by the temperature stress of cold and hot alternation. Generally, high-carbon alloy steel can obtain high hardness after heat treatment, but it has poor toughness and is prone to surface cracking, and is not suitable for use. The selected steel should reduce the number of polishing and repair cycles for injection molds and maintain the dimensional accuracy of the cavity for a long time to achieve the service life of mass production.


Corrosion resistance of injection mold standard parts


For some plastic varieties, such as PVC and flame-retardant plastics, corrosion-resistant steel should be considered.


In addition, when selecting materials for injection mould base parts, it is necessary to prevent scratches and adhesion. If there is relative movement between two surfaces, materials with the same structure should be avoided as much as possible.

Hot Precision Plastic Injection Molding Products
Precision Plastic Injection Molding News
  • What Are the Injection Molding System Components?What Are the Injection Molding System Components?March 31, 2023The gating system refers to the portion of the plastic that enters the mold cavity from the nozzle, including the main runner, cold slug well, sprue and gate, etc.The gating system, also known as the ...view
  • The Market Potential Of Large Precision Mold Is EnormousThe Market Potential Of Large Precision Mold Is EnormousSeptember 16, 2022With numerical control processing equipment levels are increased, more and more companies are increasing plastic mold development efforts, plastic molds have become a most attractive varieties of mol...view
  • How to Improve the Quality of Injection Molding?How to Improve the Quality of Injection Molding?March 31, 2023Mold is the mother of industry, and the development of the mold industry is closely related to the entire industrial level. With the progress of technology, the requirements for molds are also constan...view
  • Mold Road Bumps But Has A Bright FutureMold Road Bumps But Has A Bright FutureSeptember 16, 2022Thanks to China's automobile, electronics, IT industry, packaging, building materials, daily necessities mold development of large user industries, current mold industry market in China is develop...view
  • Home Appliance Mould Industry: Mold Parts 80% ShareHome Appliance Mould Industry: Mold Parts 80% ShareSeptember 16, 2022Appliance parts from China mould industry layout, home appliances plastic mold manufacturing concentrated in Guangdong, Zhejiang, Shandong, appliance parts foam mould is concentrated in chuzhou area, ...view
  • The Backbone of Molding: Exploring Mold Standard PartsThe Backbone of Molding: Exploring Mold Standard PartsOctober 10, 2023Mold standard parts are the unsung heroes of the molding industry. They are the essential components that form the backbone of every molding process, playing a pivotal role in ensuring precision, effi...view