CUTTING OF DUCTILE SHEET BY ASYMMETRIC POINTED TOOLS

The cutting of ductile sheet metal by asymmetric pointed tools is mode lled by extending an earlier analysis of guillotining [1]. The experim ental load-displacement diagrams agree with the results of rigid-plast ic effective fracture toughness in the cut plane of intense sheer. The cut edges of the triangular holes displayed the characteristic featur es of guillotined sheets, but the edges of the spiral offcuts did not, owing to the absence of a cutting tool or anvil below the unsupported test discs. Final fracture in this configuration is a combination of tool-induced cracking from the approach side and natural tearing on th e distal side. (C) 1998 Elsevier Science S.A. All rights reserved.