In recent years, with the rapid development of machining scale and manufacturing level of superhard materials, superhard materials have been more and more widely used in China. In the superhard materials and products exhibition area of 2011 China (Zhengzhou) International abrasive grinding exhibition held from November 11 to 13, dozens of superhard materials and tool manufacturers jointly showed the audience the rapid development and great progress of domestic superhard materials.
In the current tool market, the tool materials that occupy the market share are still high-speed steel and cemented carbide, but the hardness of these tools is only 2000 ~ 3000hv. If bonding materials are added, the overall hardness is less than 2000hv. For difficult machining materials and high-speed and high-precision machining, tool materials with low hardness are no longer competent. Superhard cutting tools represented by diamond and cubic boron nitride (CBN) quickly occupied this market. Among them, diamond has extremely high hardness and wear resistance. Its hardness can reach 10000hv. It is the hardest tool material, and its thermal stability can reach 700 ℃ ~ 800 ℃. The hardness of cubic boron nitride is second only to diamond (up to 8000hv ~ 9000hv), and its thermal stability is higher (up to 1250 ℃ ~ 1350 ℃).
In the interview, the reporter of electromechanical business daily learned that superhard material tools have the characteristics of high processing efficiency, long service life and good processing quality. In the past, they were mainly used for finishing. In recent years, due to the improvement of the production process of artificial superhard tool materials, the control of raw material purity and grain size, the use of composite materials and hot pressing process, the scope of application has been expanding. In addition to being suitable for general finishing and semi finishing, It can also be used for rough machining, which is internationally recognized as one of the most promising tool materials to improve productivity. Using superhard materials to process steel, cast iron, non-ferrous metals and their alloys, the cutting speed can be one order of magnitude higher than that of cemented carbide, and the tool life can be dozens or even hundreds of times higher than that of cemented carbide. At the same time, its emergence also changes the traditional process concept. The use of superhard tools can often directly replace grinding (or polishing) with turning and milling. For the processing of hardened parts, a single process can be used to replace multiple processes, which greatly shortens the process flow.
Diamond cutting tools have high hardness and wear resistance. They can effectively process non-ferrous metals such as copper and aluminum and their alloys, ceramics, final sintered cemented carbide, various fiber and particle reinforced composites, etc. Compared with diamond, cubic boron nitride has higher thermal stability, greater chemical inertia to iron group elements and strong adhesion resistance. It is more suitable for processing all kinds of hardened steel, thermal spraying materials, chilled cast iron and cobalt based and nickel based difficult cutting materials above HRC35.
Nowadays, the advantages of superhard cutting tools in machining have been well known by the majority of users, and have been more and more widely recognized and applied, with huge market demand. From the perspective of superhard materials, China has obvious resource advantages. The output of diamond accounts for more than 80% of the world's total output, and the output of cubic boron nitride (CBN) accounts for more than 60% of the world's total output. It is already a superhard material producer. In terms of superhard materials, China has entered the ranks of the world's strong countries, and China's superhard material industry has taken the lead in becoming one of the industries with a voice in the world. However, in fact, at present, domestic superhard material tools are still in the initial and growing stage. Some enterprises are working towards high-end and precision superhard material tools, and have made many achievements, but they still can not meet the growing market demand. Superhard material tools will occupy a more important market position in the tool Market in the future.
