Dynamic recrystallization behavior of a Mo-2.0%ZrO2 alloy during hot deformation

• Published in: International journal of refractory metals & hard materials Vol. 109; p. 105983
• Main Authors: Xu, Zhaoning, Xu, Liujie, Xiong, Ning, Yao, Yuan, Li, Xiuqing, Wei, Shizhong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2022
• Subjects: Dynamic recrystallization; EBSD; High temperature deformation; Microstructure evolution; Mo-2.0%ZrO2; High temperature deformation; Mo-2.0%ZrO2; Dynamic recrystallization; Microstructure evolution; EBSD
• ISSN: 0263-4368; 2213-3917
• DOI: 10.1016/j.ijrmhm.2022.105983

The high-temperature deformation process of molybdenum alloy reinforced by 2.0%ZrO2 was tested in the temperature range of 1100–1400 °C and strain rate range of 0.005–1 s−1 in a vacuum environment, and the microstructure evolution during the high-temperature deformation process was investigated. Based on the Arrhenius model, the transient equation of the Mo-2.0%ZrO2 alloy was established, and the relationship between deformation temperature, strain rate and flow stresses was described. The flow stresses of the Mo-2.0%ZrO2 alloy were characterized by dynamic recovery and recrystallization in the deformation process. Dynamic recrystallization of the Mo-2.0%ZrO2 alloy mostly occurs at high temperatures and low strain rates. At higher strain rates (0.1–1 s−1) and low temperatures (1100–1200 °C), chain-like fine crystals and fine equiaxed grains were found, indicating that partial dynamic recrystallization occurred. At low strain (0.005 s−1) and low temperatures (1100–1200 °C), equiaxed grains were found to demonstrate continuous dynamic recrystallization. Coarse equiaxed grains were found at low strain (0.005–0.1 s−1) and high temperature (1300–1400 °C), indicating a dominance of grain growth. The Mo-2.0%ZrO2 alloy have low activation energy compared with Mo-Al2O3 alloy, which is beneficial to hot working. The Mo-2.0%ZrO2 alloy has two typical textures, 〈100〉//ND and 〈111〉//ND, after high temperature deformation. As the strain decreases, there is enough kinetic energy to reduce the basal plane deviation in TD and RD directions, and the texture of Mo-2.0%ZrO2 alloy is dominated by 〈100〉//ND. •Dynamic recrystallization of Mo-ZrO2 alloy is ruled by strain rates and deformation temperature.•Chain-like fine crystals and fine equiaxed grains were found to indicate partial dynamic recrystallization at higher strain rates and low temperatures.•Equiaxed grains were found to demonstrate continuous dynamic recrystallization at low strain and low temperatures.•Coarse equiaxed grains were found to indicate a dominance of grain growth at low strain and high temperature.•The texture of Mo-ZrO2 alloy is dominated by //ND at low strain.