2001 Volume 67 Issue 656 Pages 1163-1169
This paper presents the effects of TiN coating and (Al, Ti) N coating films on the rake face of hob on the behavior of crater wear mainly, flank wear and finished surface roughness with using two kinds of high-speed steel hob substrates in dry hobbing. Experiments were carried out using a fly tool. As the results obtained, it was found that the tool made of corresponding to SKH 55 coated with (Al, Ti) N has no crater wear and also shows a best performance in terms of the flank wear and surface finish, and the corresponding to SKH 55+ (Al, Ti) N fully coated tool is suitable in dry hobbing. It was also suggested that the crater wear mechanism on the coated rake face is due to the plastic deformation of the coating film, which causes its delamination, after appearing the substrate, the crater wear increased by the abrasive action with the cutting chips.