摘要
选用Al-Li-Cu-Mg系铝锂合金2060,开展搅拌摩擦焊对接接头显微组织与析出相演变规律研究.搅拌摩擦焊对接接头,呈现典型的母材、热影响区、热机影响区和焊核区四区分布特点.母材为双向板条组织,在α板条中有大量三角形AlCu2Mn化合物析出,但在其它相区,当受到热影响时,该相消失;热影响区组织粗大,热机影响区晶粒受到机械力作用,前进侧拉长,后退侧破碎;焊核区为等轴晶组织,出现了高温析出相AlxCuxMn,均布于整个焊核区域.接头显微硬度在母材区最高,热影响区最低,焊核区低于母材,稳定在115 HV.
In this paper, the microstructure and precipitation phase evolution of friction stir welding butt joint were investigated, for the Al-Li-Cu-Mg-based aluminum-lithium alloy 2060. The cross section of Friction stir welding butt joint could be divided into four distinctive regions： base metal zone, heat-affected zone, thermal mechanically affected zone and weld nugget zone. The microstructure of the base metal consisted of bidirectional slat, large numbers of triangular AlCu2Mn compound precipitated from ot lath, which would disappear when subjected to heat action in other zones. The heat-affected zone showed coarse crystal particles, and grain morphology was changed under the action of mechanical force in the thermal mechanically affected zone, stretched at the advancing side and compressed at the retreating side. The weld nugget zone was equiaxed grain structure, the high temperature precipitated phase AI Cu Mn distributed throughout the joint region uniformly. The highest microhardness existed in the base metal zone, and the lowest value was located in the heat-affected zone, with the weld nugget zone steadying at 115 HV, a little lower than the base metal.
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
2014年第1期118-122,共5页
Materials Science and Technology
关键词
铝锂合金
搅拌摩擦焊
显微组织
相
显微硬度
Al-Li alloy
friction stir welding
microstructure
phase
microhardness
