Solid state recycling of Mg-Gd-Y-Zn-Zr alloy chips by isothermal sintering and equal channel angular pressing  

作　　者：Yanbo Pei Hongjun Ma Meng Yuan Bugang Teng 

机构地区：[1]School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China [2]National Key Laboratory for Precision Hot Processing of Metals,Harbin Institute of Technology,Harbin 150001,China

出　　处：《Journal of Magnesium and Alloys》2024年第7期2725-2740,共16页镁合金学报（英文）

基　　金：supported by the fund of the National Natural Science Foundation of China(51875127,52275322).

摘　　要：The Mg-7Gd-4Y-2Zn-0.5Zr alloy chips were successfully recycled through isothermal sintering and equal channel angular pressing(ECAP).The mechanical properties and microstructure evolution of samples during the recycling process were studied in detail.The eutectic phases in the as-cast alloy transform into long period-stacking ordered(LPSO)phases after homogenization,which can improve the plasticity of the material.After isothermal sintering,the density of the sample is lower than that of the homogenized sample,and oxide films are formed adjacent to the bonding interface of the metal chips.Hence,the plasticity of the sintered sample is poor.Dense samples are fabricated after ECAP.Although the grains are not refined compared to the sintered sample,the microstructure becomes more uniform due to recrystallization.Fiber interdendritic LPSO phase and kinked 14H-LPSO phase are formed in the alloy due to the shear deformation during the ECAP process,which improves the strength and plasticity of the sample significantly.Furthermore,the basal texture is weakened due to the Bc route of the ECAP process,which can increase the Schmid factor of the basal slip system and improve the elongation of the sample.After 2 ECAP passes,the fully densified recycled billet shows superior mechanical properties with an ultimate tensile strength of 307.1 MPa and elongation of 11.1%.

关 键 词：Mg-Gd-Y-Zn-Zr alloy Solid state recycling Microstructure evolution LPSO phase Equal channel angular pressing 

分 类 号：TG379[金属学及工艺—金属压力加工] TG146.22[一般工业技术—材料科学与工程]