Computer Models for the Mechanics of Three-Dimensional Cutting Processes—Part II: Results for Oblique End Turning and Drilling

Abstract

Using the method described in Part I, numerical models for predicting chip form and the principal components of power consumption are developed for oblique end turning and drilling. Applying the method involves mainly specifying appropriate sets of independent variables for minimization calculations. Results predicted using the rigid-viscoplastic material model are compared with measurements from unlubricated tests on steel and aluminum alloy samples. The agreement between predicted and measured results for turning is generally good, particularly for chip thickness values, chip-tool contact lengths, and the qualitative effect of varying the depth of cut. The agreement is not as good for drilling; in drilling the main cutting edge torque contribution and qualitative effects of varying the spindle speed and feed rate are accurately predicted, but the average chip thickness is consistently underestimated while chip radii of curl are overestimated. The lack of agreement for the last two outputs appears to be due to constraint from the hole drill flute surf aces which would limit maximum radii of curl.