Achievement of excellent high-temperature mechanical properties of AZ31/Mg3Y laminated composite by in situ synthesis of Al-Y precipitates

Abstract

Listen

Translate article

In this study, the AZ31 alloy and Mg3Y alloy sheets were bonded by accumulative rolling bonding to prepare AZ31/Mg3Y laminated composite, and a multitude of fine Al-Y precipitates were in-situ synthesized in the composites by following diffusion annealing. The primary precipitate phases are Al2Y and Al2Y3, and they respectively follow the orientation relationships of [−112] Al2Y//(Moreno et al., 2001; Dong et al., 2021; Ouyang et al., 2021; Rzychoń et al., 2009; Kondori and Mahmudi, 2017; Fu et al., 2017; Lin et al., 2018; Yuan et al., 2001; Zhang et al., 2008; Dong et al., 2022) [11-20] Mg, [011] Al2Y3 (particle shape)//(Moreno et al., 2001; Dong et al., 2021; Ouyang et al., 2021; Rzychoń et al., 2009; Kondori and Mahmudi, 2017; Fu et al., 2017; Lin et al., 2018; Yuan et al., 2001; Zhang et al., 2008; Dong et al., 2022) [11-20] Mg, and [−112] Al2Y3 (network shape)//(Moreno et al., 2001; Dong et al., 2021; Ouyang et al., 2021; Rzychoń et al., 2009; Kondori and Mahmudi, 2017; Fu et al., 2017; Lin et al., 2018; Yuan et al., 2001; Zhang et al., 2008; Dong et al., 2022) [11-20] Mg. The AZ31/Mg3Y composite with diffusion annealing exhibits excellent comprehensive mechanical properties with a UTS of 255 MPa and fracture elongation of 19 % at room temperature. At 300oC, the AZ31/Mg3Y composite treated by diffusion annealing has the highest UTS of 155 MPa, which is much higher than both individual Mg3Y (114 MPa) and AZ31 (78 MPa) alloys. The Al-Y precipitates possess high thermal stability and can still impede dislocation slipping during the deformation process at elevated temperatures, which has a pivotal contribution to achieving the exceptional high-temperature mechanical properties of AZ31/Mg3Y composite.