A Slip-Line Field Solution for Machining with Discontinuous Chips

Abstract

The importance of establishing a realistic model of the title problem is stressed, and this is achieved by studying the process experimentally using ciné photography. Development of the discontinuous chip was traced carefully during the whole cycle of its formation and disposal, particular attention being paid to the extent and history of the plastic zone, and subsequent fracture and crack propagation. It was interesting to observe that for the material considered, namely low carbon steel, the surfaces of the crack and chip were all sensibly straight, and cutting of the next chip began before separation of the one under consideration. It is suggested that discontinuous chip machining could perhaps be used as a method of evaluating strain rate dependencies in fracture mechanics in the same way that continuous chip machining offers possibilities for deriving stress-strain curves at high rates of strain.