ECAP with back pressure for optimum strength and ductility in aluminium alloy 6016--Part 2: Mechanical properties and texture

摘要

The simultaneous increase in strength and ductility of aluminium alloy 6016 processed by equal channel angular pressing (ECAP) was investigated. A complete study of microstructure, texture and mechanical properties after ECAP processing with and without back pres?sure was carried out for the O temper. The simultaneous increase in strength and ductility of AA6016-O with number of ECAP passes was explained by the use of back pressure during ECAP. A maximum ductility of ~100 was obtained at the temperature of 200 °C and strain rate of 10~~(-4) s~(-1), which is a significant improvement on the ductility exhibited by AA6016 (~89) after a conventional thermo-mechanical treatment at a much higher temperature of 500 °C. The mechanical behaviour was interpreted in the context of the textures developed in the material. A significant amount of texture rotation due to applied back pressure was found.