b)Flank angle
The strength of cutting edge will be impaired if increase flank angle ,meanwhile ,the wear area in flank is bigger and bigger .In the meanwhile ,the bigger flank angle ,the more serious of cutting vibration.
c)Helixl angle
When the helix angle is smallest ,the cutting edge is longest plunged into the graphite work-piece in the same cutting flute ,meanwhile its cutting resistance and the cutting impacting strength are the biggest ,consequently ,the wear ,milling force and cutting vibration are the max too .When the helix angle is comparatively big,the extent of deviation from the surface in the direction of the milling force is big, in addition ,the cutting –impacting strength on graphite work-piece is intensified due to moulder ,leading to increase of wear ,milling force and cutting vibration .Therefore ,the change of the angle of cutting tools resulting in its wear ,milling force and cutting vibration problems mailing due to the comprehensive influence of the rake, flank and helix angels .So when we select these parameters ,we have to pay more attention to that .
The Coating Of Cutting Tools
The diamond coating for cutting tools with high hardness, good wear-resistance and low friction coefficient, at present, the diamond coating is the best selection for the cutting tools of graphite processing, also enable to show superior performance the tools .The advantage for the tungsten carbide cutting tools with diamond coating is that it is integrated the hardness of diamond and the toughness and fracture strength of the tungsten carbide. However ,the diamond coating technology is still under the initial stage in China now ,meanwhile it needs high investment cost ,so the diamond coating would not be developed too much .On the contrary ,we are capable to optimize the cutting angle ,material ,improve the common coating structure on the general cutting tools ,in some extent ,we can use them to machine graphite .
