An investigation of 3-D curled chip in machining - Part 2: Simulation and validation using Fe techniques

This paper presents a finite element modeling approach for the 3-D curled c hip. Four different chip types, with varying complexities are modeled using this approach. The complexities include chip twist, serrations on the inne r radius of the chip, thickness variation along the length of the chip, etc . The chip is treated as a 3-D elastic beam and the neutral axis of the chi p is modeled as a 3-D spiral with instantaneously varying center and curl r adius. Bending and shear stresses generated in the chip show very distinct patterns. Comparisons made between the mechanics-based and finite element m odels show good correlation in the magnitude and location of the failure st resses. The 3-D chip breaking pattern was also observed using high-speed fi lming techniques, and comparisons made between the FE model and experimenta l results show good correlation.