Prediction of Chip Morphology and Formation in High Speed Milling of Hardened Steels

Abstract:

A P20 steel are machined in the milling speed range of 200 to 942m/min. The morphology and formation of the chips are investigated at various speeds. The serrated chips with adiabatic shear band are observed at a high milling speed. The transition from continuous to serrated chip formation is favored by the increase in work material hardness and milling speed. The study assumes that the chip segmentation is only induced by adiabatic shear banding, without material failure in the primary shear zone. Based on adiabatic shear theory, using the JC and the power material constitutive equation, the modified material model which takes into a strain softening is developed for prediction of the serrated chip formation. Experimental measurements are compared with the simulation results.

• Periodical: Advanced Materials Research (Volumes 1120-1121)
• Pages: 1145-1152
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1120-1121.1145
• Online since: July 2015
• Authors: Jun Zhong Pang*, Xiao Bin Huang, Dou Dou Chang, Jie Pan
• Keywords: Chip Morphology, Finite Element Method (FEM), High Speed Milling, Modeling

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