What is the common sense of diamond coating in diamond tools

Diamond tool has the advantages of extremely high hardness and wear resistance, low friction coefficient, high elastic modulus, high thermal conductivity, low thermal expansion coefficient, and little affinity with non-ferrous metals. Before choosing and using diamond coated tools, users need to know the following common sense about diamond tools:
1, diamond coating tool life is different
As with any other tool, the life of diamond-coated tools varies, depending on the material being cut, the feed rate and cutting speed selected, and the geometry of the workpiece. In general, the life of diamond-coated tools for processing graphite is 10 to 20 times longer than that of uncoated carbide tools, and in some cases may even be longer. In this way, almost any machining task can be completed with a single tool without the need for tool change due to tool wear, avoiding machining interruption and recalibration, and making it possible to achieve unattended machining. It is also possible to obtain long tool life in the machining of composite materials. It has been reported that the life of diamond-coated tools can be up to 70 times longer than that of uncoated carbide tools for machining difficult composite materials such as high density glass fiber, carbon fiber and G10-FR4.
2. Difference between CVD diamond coating and amorphous diamond coating
Amorphous diamond coating is a kind of carbon film deposited by PVD process. It has both a part of diamond SP3 bond and a part of carbon SP2 bond. Its film forming hardness is high, but lower than diamond film hardness; It is also a little thinner than the diamond film we normally deposit. When processing graphite, the life of amorphous diamond coated tool is 2-3 times that of uncoated carbide tool.
3. Problems existing in diamond tools
Spalling of diamond coating can be prevented. Spalling of diamond coating is a serious and common problem with diamond-coated tools (especially when working with materials such as carbon fiber) and can lead to unpredictable tool life. In the late 1990s, the chemical properties of the interface were identified as an important factor affecting the adhesion properties of diamond coatings.