Hardware mold material

In addition to the reasonable coordination of the matrix with high enough strength and toughness, the surface performance of the mold is very important to the working performance and service life of the mold. These surface properties refer to: wear resistance, corrosion resistance, friction coefficient, fatigue performance, etc. The improvement of these properties, which is solely dependent on the improvement and improvement of the matrix material, is very limited and uneconomical, and through surface treatment technology, it is often possible to receive a multiplier effect, which is why the surface treatment technology has developed rapidly.

The surface treatment technology of the mold is a system engineering that changes the shape, chemical composition, organization structure and stress state of the surface of the mold through surface coating, surface modification or composite treatment technology to obtain the desired surface performance. From the surface treatment, it can be divided into: chemical methods, physical methods, physicochemical methods and mechanical methods. Although new processing technologies aiming to improve the surface performance of molds are constantly emerging, the main applications in mold manufacturing are nitriding, carburizing and hardened film deposition.

The nitriding process includes gas nitriding, ion nitriding, liquid nitriding, etc. In each nitriding method, there are several kinds of nitriding technologies, which can adapt to the requirements of different steel types and different workpieces. Because the nitriding technology can form a surface with excellent performance, and the nitriding process has a good coordination with the quenching process of the mold steel, and the nitriding temperature is low, no intensive cooling is required after nitriding, and the deformation of the mold is extremely small, so the mold Surface hardening was adopted earlier by nitriding technology, and it is also the most widely used.

The purpose of carburization of the mold is mainly to improve the overall strength and toughness of the mold, that is, the working surface of the mold has high strength and wear resistance. The technical idea introduced from this is to use a lower-grade material, that is, by carburizing and quenching To replace higher-grade materials, thereby reducing manufacturing costs.

Hardened film deposition technology is currently more mature CVD, PVD. In order to increase the bonding strength of the surface of the film workpiece, a variety of enhanced CVD and PVD technologies have now been developed. The hardened film deposition technology was first applied to tools (knives, cutting tools, measuring tools, etc.) with excellent results. Many tools have adopted hardened film coating as a standard process. Since the 1980s, the mold has adopted the coating hardening film technology. Under the current technical conditions, the cost of hardened film deposition technology (mainly equipment) is relatively high, and it is still only applied to some precision and long-life molds. If a heat treatment center is established, the cost of coating the hardened film will be greatly reduced If more molds adopt this technology, it can improve China's mold manufacturing level as a whole.

Surface treatment technology has been widely used in molds, and has made significant progress and huge economic benefits in improving mold life and product quality. However, there is still a gap between the application and development of advanced surface technology compared with foreign countries. Full application of surface treatment technology is an important economic and efficient means to improve the life of the mold, and it is also the only way to develop modern molds. Research and development of surface treatment technology suitable for precision and large molds is the focus of the development of mold surface technology And difficult.