Development of small radius ball end mill for deep precision machining

3rd report:Influence of tool material and coating film on its deflection

Abstract

Machining of complex shapes and deep micro-cavities in dies and molds is mostly carried out by the electrical discharge machining process. However, it may not be possible to sufficiently minimize delivery deadlines and reduce the cost of dies and molds. Therefore, precision machining methods using a small-radius ball end mill capable of machining deep cavities in miniature dies and molds is proposed as a substitute for electrical discharge machining. The results of experiments confirmed that long tool life of the ball end mill can be maintained by changing the coating film material and the edge shape of the small-radius ball end mill, and it is possible to obtain the required surface finish in the work pieces.