A Study on the Behaviour of Strain during Cutting Process : Influence of Repeated Cutting

The mechanism of strain analized by photoelastic coating method in aluminum has been reported in the previous papers. On the basis of those experimental results, the authors investigate the influence of repeated cutting on strain distribution in the workpiece. Here the repeated cutting means to cut the workpiece of hardened aluminum by the process of primary machining in the same direction. In the primary machining process an annealed aluminum is machined using cutting tool or vurnishing tool. The present experiment gives the following results. (1) Repeated cutting, wihtin the cutting depth of the primary process, shows. (1-1) Shearing angle is particularly larger than primary cutting and the fact is available for machinablility. (1-2) Cutting force is apparently larger than primary cutting. (1-3) The difference of strain distribution between repeated cutting and primary one is very small. (2) The larger the primary cutting speed is, the smaller the value of the effective depth as above. (3) Five different tools used in primary machining resulted in less effective upon repeated cutting.