Prediction of Surface Fracture of 6061 Al Processed by Equal-Channel Angular Pressing

Abstract:

Improving the efficiency of equal-channel angular pressing (ECAP) necessitates predicting the location of fracture and the number of ECAP passes required when fracture is formed. However, the damage mechanism in ECAP-processed materials remains insufficiently understood. Surface fracture formation during the ECAP of 6061 Al-T4 alloy was investigated by finite element simulation and experimentation. The simulation of damage distribution in the sample was based on the Cockcroft and Latham criterion. Fracture formed in the upper and lower surfaces of the sample, a finding that is in good agreement with the simulation results for damage factor. A critical damage factor, calculated from the experimental data, accurately predicted the number of ECAP passes required when surface fracture is formed. Tensile stress was caused by various strain rates in different parts of the sample cross-section as the sample was pressed through the bend channel; this stress was the main driver of damage formation.

• Periodical: Applied Mechanics and Materials (Volumes 217-219)
• Pages: 2373-2378
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.217-219.2373
• Online since: November 2012
• Authors: Qing Zhou, Wen Jie Chen, Jun Xu, Yu Peng Duan
• Keywords: AA6061 Aluminum Alloy, Cockcroft and Latham Criterion, Equal-Channel Angular Pressing (ECAP), Fracture, Mechanical Property

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