Orientador : Nivaldo Lemos Cupini

Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Campinas

Resumo: Não informado

Abstract: The effect of the drill rotation and geometry on the drilling process of the free machining ABNT303 and the ABNT316 austenitic stainless steels has been studied. Thus, once the feed force and the drill diameter are kept constant, it can be observed how the feed values vary as the drill...

Abstract: The effect of the drill rotation and geometry on the drilling process of the free machining ABNT303 and the ABNT316 austenitic stainless steels has been studied. Thus, once the feed force and the drill diameter are kept constant, it can be observed how the feed values vary as the drill rotation and geometry are changed in the drilling process with or without a previous hole. Also, the machinability rating variation of the 316 steel relative to the 303 steel was detected. The low efficiency of the process can be traced to the high deformation caused by the transversal cutting edge if low rotations are concerned. As the rotation was increased and/or the transversal cutting edge action was partially or completely, avoided by the drill sharpening or the previous hole execution, the feed values increased, what implies a higher process efficiency. This can be associated with lower values of the deformation degree. The 316 steel machinability rating increase associated with a higher process efficiency makes clear that the 316 steel process efficiency improvement was greater than that for the 303 steel