An investigation of 3-D curled chip in machining - Part 1: A mechanics-based analytical model

This paper presents an analytical model of the 3-D curled chip that is comm only produced in oblique machining. The chip model is based on a 3-D spiral with continuously varying center and curl radius. Stresses in the chip are analyzed by an energy-based approach. Bending and torsional shear stresses in the chip are generated based on input reaction forces. A case study wit h typical input values of reaction forces is analyzed for finding the magni tude and location of the maximum stresses. Also, the octahedral shear stres s is proposed as a comprehensive 3-D chip failure criterion, because it com bines the individual effects of the bending and shear stresses.