THREE-DIMENSIONAL FINITE ELEMENT PREDICTION OF MACHINING- INDUCED STRESSES

摘要

Controlling residual stress in machined workpiece surfaces is necessary in situations where service requirements subject structural members to cyclic fatigue loading. It is desirable to have a predictive capability when attempting to optimize machined parts for cost while taking into account residual stress considerations One such method of machining modeling is application of the finite element method (FEM). A three-dimensional FEM model is presented which includes fully adaptive unstructured mesh generation, tight thermo-mechanically coupling, deformable tool-chip-workpiece contact, interfacial heat transfer across the tool-chip boundary, momentum effects at high speeds and constitutive models appropriate for high strain rate, finite deformation analyses. The FEM model is applied to nose turning operations with stationary tools. To substantiate the efficacy of numerical and constitutive formulations used, metal cutting tests are performed, residual stress profiles collected, and validation comparison is made.