| Superplasticity of a fine–grained Mg–9Gd–4Y–0.4Zr alloy assessed using shear punch testing |
| Paper ID : 2548-UFGNSM13-FULL |
| Authors: |
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Reza Alizadeh baloochi1, Terence G. Langdon2 1tehran, North Karegar, Engineering faculty of University of tehran 2Faculty of Engineering and the Environment, Southampton SO17 1BJ |
| Abstract: |
| The superplasticity of an extruded fine-grained Mg–9Gd–4Y–0.4Zr alloy was investigated through measuring its strain rate sensitivity by shear punch testing (SPT). Shear punch tests were conducted at shear strain rates in the range of 3 × 10−3 to 2 × 10−1 s−1, and temperatures in the range of 300–500 °C. Results indicated that the strain rate sensitivity index (m) increases from about 0.11 at 300 °C to about 0.40 at 450 °C and then decreases to 0.32 with a further increase in test temperature. The strain rate sensitivity index of 0.40 and activation energy of 140 kJ/mol are indicative of a superplastic deformation behavior dominated by grain boundary sliding accommodated by lattice diffusion at temperatures above 400 °C. |
| Keywords: |
| Mg–Gd–Y–Zr alloy; Superplasticity; Strain rate sensitivity; Shear punch |
| Status : Paper Accepted (Oral Presentation) |
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