2. Development of PVD technology abroad PVD technology appeared in the late 1970s. Because its process temperature can be controlled below 500 °C, it can be used as a final treatment process for the coating of high speed steel tools. Since the PVD process can greatly improve the cutting performance of high-speed steel tools, the technology has been rapidly popularized since the 1980s. By the end of the 1980s, the proportion of PVD coatings for high-speed steel complex tools in industrialized countries has exceeded 60%. . Previous Next Building use safe glass, can resist the hurricane of 100 kilometers per hour with gravel, special safety glass can resist the bullet shoot, prevent the thief home invasion and shielding high-energy rays (e.g., x-rays), to prevent the spread of fire, and other functions, the main body of glass structure of modern architecture is of special significance, Common safety glass tempered glass, laminated glass, bulletproof glass, film glass, etc., film glass as a new technology, has been included in the national "eleventh five-year" promotion project. Smart Film Sheet, Smart Film Roll, LC Film, SPD Film, PVC Film Tianqixun Technology , https://www.tqxdisplay.com
The successful application of PVD technology in the field of high-speed steel tools has attracted the attention of manufacturing industries all over the world. People are competing to develop high-performance and high-reliability coating equipment, and also expand their application fields, especially in cemented carbide. The application in ceramic tools has been further studied. The results show that compared with the CVD process, the PVD process has a low processing temperature, and has no effect on the flexural strength of the tool material below 600 °C (test results are shown in Table 1); the internal stress state of the film is compressive stress, which is more suitable for The coating of cemented carbide precision complex tools; PVD process has no adverse impact on the environment, in line with the development direction of modern green manufacturing. With the advent of the era of high-speed machining, the proportion of high-speed steel tool applications has gradually declined, and the proportion of applications of cemented carbide tools and ceramic tools has become an inevitable trend. Therefore, industrialized countries have been working on cemented carbide tools since the early 1990s. Research on PVD coating technology has made breakthroughs in the mid-1990s. PVD coating technology has been widely used in carbide end mills, drill bits, step drills, oil hole drills, reamers, taps, and indexable Coating treatment of milling inserts, profiled tools, welding tools, etc.
Table 1 Effect of PVD Coating on Bending Strength of Cemented Carbide Materials at Different Temperatures Carbide Grade - Average Bending Strength (MPa) - Uncoated - Coating (300 ° C) - Coating (600 ° C) - Coated Layer (700 ° C)
M20-2109-2266-2129-2059
M30-2285-2469-2370-1894
At present, PVD technology not only improves the bonding strength between the film and the tool base material, but also the coating composition from the first generation of TiN to the multi-composite coating of TiC, TiCN, ZrN, CrN, MoS2, TiAlN, TiAlCN, TiN-AlN, CNx, etc. Floor. The emergence of nanoscale coatings such as ZX coatings (ie TiN-AlN coatings) has made a new breakthrough in the performance of PVD coated tools. The new coating has high bonding strength with the substrate, the hardness of the coating film is close to CBN, the oxidation resistance is good, the peeling resistance is strong, and the surface roughness of the tool can be significantly improved, and the shape and precision of the cutting edge of the precision tool are effectively controlled. Precision machining quality is comparable to uncoated tools.
After decades of research and development, various tool coating processes have been widely used in hard alloy and high speed steel cutting tools. The main development stages and application fields of the coating process are shown in Table 2.