Superplastic behavior of fine-grained extruded ZK61 Mg alloy

The superplasticity of a fine-grained extruded ZK61 magnesium (Mg) alloy was investigated by tensile testing at various elevated temperatures and strain rates. The results demonstrated the strain rate sensitivity (m-value) similar to 0.51 and similar to 0.4 and stress exponent (n-value) similar to 1.96 and similar to 2.5 at temperatures 673 K and 623 K, respectively. The numerical simulation revealed that the activation energy (Q-value) was in the range of 92.9-146.7 kJ/mol. Therefore, the high elongation to fracture (FE) similar to 400% and similar to 334% were achieved at temperatures 673 K and 623 K under tensile loading at a strain rate of 0.001 s(-1). The microstructure was thermally stable at elevated temperatures and attributed to MgZn2 phase particles. Based on m-value, n-value, FE, average Q-value similar to 114 kJ/mol, and thermally stable microstructure, it was found that the governing deformation mechanism was the intra-granular slip. These all feathers assisted in understanding the superplastic behavior of the ZK61 Mg alloy.

Automated summary

The study investigated the superplasticity of fine-grained extruded ZK61 magnesium alloy at elevated temperatures, showing high elongation to fracture and a governing deformation mechanism of intra-granular slip.