摘要
为了研究AZ31镁合金FSW过程中的微观结构演化与组织、性能间的关联性,采用Monte Carlo和试验相结合研究焊接区域微观结构演化,测试焊接区的组织与性能,构建微观结构演化和组织、性能间的Hall-Petch关系式。结果表明:AZ31镁合金的FSW前进侧和后退侧硬度的最小值均在搅拌针和轴肩之间的覆盖区域,且后退侧材料硬度较前进侧稍高。搅拌头转速增加时,镁合金FSW搅拌区晶粒增大,说明搅拌头旋转导致的温度变化对搅拌区的晶粒形貌变化具有重要影响。随着搅拌头转速的增加,镁合金FSW温度升高,同时应变率随之增加,温度升高导致晶粒变大,应变率增加导致形核率增加从而导致晶粒变小,综合作用的结果使搅拌头转速增加时镁合金FSW搅拌区晶粒随之增大。
In order to study the relationship between microstructure evolution and microstructure and properties in the FSW process of AZ31 magnesium alloy,Monte Carlo and experimental methods were combined to study the microstructure evolution of the welding zone,test the microstructure and properties of the welding zone,and construct the Hall-Petch relationship between the microstructure evolution,microstructure and properties.The results show that the minimum hardness values of FSW forward side and back side of AZ31 magnesium alloy are in the covered area between the stirring needle and the shaft shoulder,and the hardness of material on the back side is slightly higher than that on the forward side.The grain in the stirred zone of magnesium alloy FSW increases with the increase of the rotational speed of the stirring head,indicating that the temperature change caused by the rotation of the stirring head has an important effect on the grain morphology.With the increase of stirring head rotational speed,the FSW temperature of magnesium alloy increases,and the strain rate increases accordingly.The increase of temperature leads to the increase of grain size,and the increase of strain rate leads to the increase of nucleation rate,which leads to the decrease of grain size.As a result,the grain size in the stirring zone of magnesium alloy FSW increases with the increase of stirring head rotational speed.
作者
张昭
刘富翰
王艺飞
李健宇
张新宇
ZHANG Zhao;LIU Fuhan;WANG Yifei;LI Jianyu;ZHANG Xinyu(School of Mechanics and Aerospace Engineering,Dalian University of Technology,Dalian 116024,China;State Key Laboratory of Structural Analysis for Industrial Equipment,Dalian University of Technology,Dalian 116024,China)
出处
《兵器材料科学与工程》
CAS
CSCD
北大核心
2024年第6期1-7,共7页
Ordnance Material Science and Engineering
基金
国家自然科学基金(12372191)。
关键词
FSW
镁合金
微观结构
力学性能
HALL-PETCH关系
friction stir welding
magnesium alloy
microstructure
mechanical property
Hall-Petch relationship
