Effect of Equal Channel Angular Pressing on Microstructure and Mechanical Properties of ZL205A Alloy

Abstract:

The evolution of microstructure of ZL205A alloy during equal channel angular pressing (ECAP) by route A at room temperature was investigated by OM, SEM and XRD, and the hardness of cast and heat treatment alloy from different strain were tested. The results showed that the grain of cast alloy were obviously refined, the massive q phase along the grain boundary were crushed, and prompts the distribution of q streamline after one pass through ECAP. After two passes of ECAP, the distribution of q phase is more uniform. After heat treatment through ECAP, the grains were also obviously refined, and elongated in axial direction, which also prompts the distribution of q streamline. The hardness was significantly improved after ECAP. The hardness of cast alloy increases from 65HV to 132HV after two passes, and that of heat treatment alloy increases from 112HV to 198HV. With the increase of extrusion passes, the number of dimples gradually increased and evenly distributed, the depth of dimples was of a similar level, and the distribution of precipitated phase is more uniform.

• Periodical: Materials Science Forum (Volume 913)
• Pages: 77-82
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.913.77
• Online since: February 2018
• Authors: Ting Biao Guo*, Qi Li, Chen Wang, Shi Ru Wei, Yi Bo Wu
• Keywords: Dislocation, Equal Channel Angular Pressing (ECAP), Fine Grain Strengthening, Microstructure, ZL205A Alloy

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