Research progress of mold materials and mold heat treatment

6 Outlook and recommendations

It can be considered that my country has established a relatively complete series of mold materials, and some of the mold materials have excellent performance, reaching the international advanced level. The research and development of mold heat treatment in my country can also be synchronized with the international, and some new mold heat treatment technologies have been promoted and applied to varying degrees.

In view of the existing problems, the following suggestions are put forward for the development of mold materials and mold heat treatment technology in my country in the future:

6.1 Accelerate the commercialization of die steel production, refined materials and die steel distribution.

Our country uses more than 200,000 tons of steel for molds every year, and it is increasing year by year. In recent years, foreign mold steel imports account for about 1/3 of the demand for mold steel, showing a gradual increase. The main problem is that my country’s mold steel has fewer varieties and specifications, and the degree of commercialization of mold steel production, refined materials, and distribution is low. In some industrially developed countries, metallurgical companies supply 50-60% of machined die steel products, while more than 80% of die steel in China is still supplied in black round bars. More and more die manufacturers require After the mold design is completed, the mold steel supplier can quickly provide the required steel, reduce the amount of stocked steel, and shorten the mold making cycle. Chinese steel production companies are not yet adapted to this commodity market mechanism, which is the increasing expansion of imported mold steel in China important reason.

6.2 Vigorously promote the application of new mold steels with excellent performance and continuously improve the series of mold steel grades

my country has developed a lot of new mold steels with certain characteristics, some of which have excellent performance, reaching or exceeding the level of similar foreign steels. However, the number of promotion and application scope of these new steels are not large enough. The main reason is that the production of mold steel in China has not yet taken the road of productization and refined materials, and the distribution method does not meet the requirements of the commodity market. These problems have been solved and these performances are good. The new type of die steel has broad promotion prospects and will produce huge economic benefits.

China already has a relatively complete series of die steel, and still needs to continuously improve its quality, expand its application, and further save the advantages and eliminate the disadvantages in the application. At the same time, selectively develop advanced mold steels to improve China’s mold steel series, such as developing powder metallurgy mold steels, multi-element free-cutting plastic mold steels, and establishing steel series for forming molds such as glass, ceramics, refractory bricks and floor tiles, etc.

6.3 Further improve the quality of die steel

Some special steel plants in my country have adopted new metallurgical equipment and processes to produce die steel, such as out-of-furnace refining, vacuum smelting, fast forging machines and precision forging machines. The quality of some die steels has been greatly improved, such as D2, P20, etc. The steel has been exported in batches, and the quality of the exported products can reach the international advanced level. Industrial developed countries have been working hard to improve the purity, density, uniformity and quality stability of die steel. Some foreign companies stipulate that [O]  10 ppm, [H]  2 ppm, S  50 ppm in high purity die steel, because further improvement of steel purity can significantly improve steel toughness and fatigue properties. For large molds, vacuum degassing and high-temperature diffusion annealing must be used to reduce the segregation of alloying elements, and isotropic forging technology is used to improve the isotropy, so that the plasticity and toughness of the mold steel in the transverse and thickness directions can reach 80″ in the longitudinal direction. More than 90%. Our country needs further work in this area.

6.4 Strengthen the promotion and application of advanced die heat treatment technology [28]

Controllable atmosphere heat treatment and vacuum heat treatment of molds should be further developed, promoted and applied. Some effective mold surface heat treatment technologies should be improved and their promotion and application should be strengthened. Improve the manufacturing level of equipment and process materials, and strengthen the construction of specialized heat treatment plants.