Development of cutting tool coating technology at home and abroad (2)
The successful application of 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 and ceramics. The application in the class tool has been studied in more depth. 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. Previous Next API 602 Gate Valve is samll forging shut off valve which widely used in all type system of thermal power plant. API 602 gate valve with solid wedge, bolt bonnet or welding bonnet type as well as full port or reduce port. Valve size from 1/2"(PN15) to 2"(PN50) matching pressure class 150(PN16) to class 2500(PN420). Valve connection can be NPT, BW, SW, RF. Api 602 Gate Valve,Alloy Steel Gate Valve,Api602 Gate Valve,Slab Gate Valve Yongjia South Trading Co.,Ltd , https://www.n-lvalve.com
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
-2109-2266-2129-
-2285-2469-2370-
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.
Table 2 Main coating process development period and application time Time - Coating composition - Coating method - Main application fields Year - TiC, TiN-CVD - Carbide tool, mold coating year - TiCN, TiC + Al2O3-CVD- Carbide tool, mold coating year-TiN-PVD-High speed steel tool coating year-TiC+Al2O3+TiN, Al-ON-CVD-Carbide tool coating year-TiCN-MT-CVD-carbide Tool Coating Year-TiCN-PVD-Carbide, HSC Milling, Drill Tool Coating Year-Diamond, CBN-CVD, PVD-Carbide Tool Coating Year-TiAlN-PVD-Carbide Milling Cutter Coating (for steel, cast iron processing)
Year - TiN, TiCN, TiC-PCVD - mold, thread cutter, milling cutter, etc. - TiAlN + CrC - PVD - car, milling titanium alloy year - TiN + TiCN (CVD) + TiN (PVD) - CVD + PVD - hard Alloy Milling Tools Year-CrN-PVD-Titanium Alloy, Copper Alloy Processing Year-MoS2-PVD-High Speed ​​Steel Complex Tool Coating Year-TiN-AlN-PVD-Carbide Milling Blade Coating Year-Thick Film Fiber TiCN-MT-CVD-Carbide Turning Tool Coating (for rough and semi-finishing)
Year-CNx-CVD, PVD-High Speed ​​Steel Tool Coating Year-TiAlCN-PVD-Carbide Blade Coating