Effects of Compression-Pass on Microstructure and Mechanical Properties of AZ80 Alloy

In the present work, as-homogenized AZ80 alloy was subjected to the multi-pass compression at the same total compression strain and different compression passes. The effects of compression-pass on microstructure and mechanical properties were investigated. Results show that the intermittent reheating stage during the multi-pass compression process plays an important role in the microstructure evolution. During the intermittent reheating process, the fine grains in the duplex-grain microstructure generated by partial dynamic recrystallization grow rapidly, which lead to the increase of the average grain size and the decrease of the difference in grain size between the coarse and fine grains. This phenomenon is more obvious by the increase of the intermittent reheating stage. It finds that the hardness mainly depends on the average grain size, and the value decreases with the increase of the average grain size. However, the ultimate tensile strength and elongation mainly depends on the grain size distribution, and the better tensile properties can be obtained when the microstructure is more homogenous.