Effect of Bi addition on microstructures and
mechanical properties of AZ80 magnesium alloy
mechanical properties of AZ80 magnesium alloy
(1. Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China;
2. New Materials Research Institute, Shandong Academy of Sciences, Ji’nan 250014, China)
2. New Materials Research Institute, Shandong Academy of Sciences, Ji’nan 250014, China)
Abstract: The effects of Bi addition on the microstructures and mechanical properties of as-cast AZ80 alloy were investigated. The results show that with the addition of Bi, the coarse eutectic phases are refined and become discontinuous; some flaky and granular Mg3Bi2 phases with a hexagonal structure of D52 are observed along the grain boundaries and between dendrites. The tensile strength and elongation increase first, and then decrease with increasing Bi content. AZ80-0.5%Bi alloy has optimum combination mechanical properties. When the content of Bi is above 1.0% (mass fraction), the amount of flaky Mg3Bi2 phase increases markedly, which splits the matrix and deteriorates the tensile strength and elongation.
Key words: AZ80 magnesium alloy; bismuth; microstructure; mechanical property