Add: No.6, No.146, The Seventh Street, Econ And Tech Development Area, Zhengzhou, Henan, China
1) the difference between CVD diamond coating and amorphous diamond coating is amorphous diamond, also known as diamond-like carbon, is a carbon film deposited by PVD process. It has some SP3 bonds of diamond and some SP2 bonds of carbon. Its hardness is very high, but it is lower than that of diamond film. Its thickness is also thinner than that of diamond film usually deposited. When the graphite is processed, the life of the amorphous diamond coated tool is 2-3 times that of the uncoated carbide tool. In contrast, CVD diamond is pure diamond coating deposited by CVD process. Tool life is 12-20 times higher than that of cemented carbide tool when machining graphite, so that the number of tool changing can be reduced, and the reliability and accuracy of machining will be improved.
(2) can not use the diamond tool in Machining Hardened Steel Diamond is composed of carbon atoms. When some materials are heated, carbon atoms are sucked out from the diamond and carbides are formed in the workpiece. Iron is one of these materials. When diamond tools are used to process iron family materials, the heat generated by friction will cause carbon atoms in diamond to diffuse into iron, resulting in early failure of diamond coatings due to chemical wear.
(3) diamond tools restrict the quality of diamond coated tools with re grinding and / or heavy coating. It is difficult to ensure the quality of diamond coated tools is pure diamond. Therefore, it takes a long time to regrinding the tools with diamond grinding wheels. In addition, the tools used to make the diamond grow. The preparation process will change the chemical characteristics of the surface of the tool. Because the coating requires precise control of the chemical characteristics, the effect of tool re coating is difficult to guarantee.
(4) the life of diamond coated tools is different. As with any other tool, the life of diamond coated tools is also different, mainly depending on the cutting material, the feed rate and cutting speed selected, and the geometry of the workpiece. In general, the life of the diamond coated cutting tools for processing graphite is 10-20 times that of the uncoated carbide tools, and may even be longer in some cases. In this way, a tool can be used to accomplish almost any processing task without changing tool due to tool wear, avoiding machining interruption and recalibration, so it is possible to achieve unattended processing. It is also possible to obtain longer tool life in the processing of composite materials.
It is reported that when processing high density glass fiber, carbon fiber and Gl0-FR4 and other difficult to process composite materials, the life of diamond coated tools can be as high as 70 times of that of the uncoated carbide tools.
(5) the problem of diamond cutting tools. The peeling of diamond coatings can prevent coating from peeling. It is a serious problem of diamond coated tools. It is also a common problem, especially when machining carbon fibers and other materials, which will lead to unpredictable tool life. In the late 90s of the last century, the chemical properties of the interface were determined to be an important factor affecting the adhesion properties of the diamond coatings. By selecting the chemical characteristics of cemented carbide with good compatibility, proper pretreatment technology and reasonable deposition reaction conditions, it is possible to reduce or eliminate the spalling of diamond coatings and achieve stable wear mode steadily. Observing the diamond wear tool with normal wear under microscope, it can be found that diamond is stably worn to the hard alloy substrate without cracking or spalling.