摘要
采用光学显微镜、透射电子显微镜、X射线衍射仪等手段,研究了基于PLC控制的电子束焊接工艺参数下及固溶时效处理后1420铝合金焊接接头的显微组织、物相组成和力学性能。结果表明,热处理后焊接接头焊缝组织由热处理前的等轴树枝晶转变为等轴晶,而枝晶间和晶界附近的共晶组织转变为强化相的数量明显增多。圆形扫描条件下,电子束流为10mA,焊接速度为800mm/min为1420铝合金的最佳焊接工艺;在该工艺条件下,热处理后的焊接接头焊缝区存在细小的纳米级Al_3Li相、球形Al_2Zr相及短棒状A1_2MgLi相;热处理后其焊接接头的抗拉强度有所上升,屈服强度和断后伸长率都有所降低。
The microstructure, phase composition and mechanical properties of 1420 aluminum alloy welded joint under the electron beam welding process parameters based on PLC control and solution aging treatment were studied by means of optical microscope, transmission electron microscope, X ray diffi＇actometer. The results show that after heat treatment, the weld microstructure of welded joint transforms from equiaxed dendrite before heat treatment to equiaxed grains, and the number of eutectic structure near the dendrite and grain boundary which transforms into strengthening phase significantly increases. Under the circular scanning condition, the optimal welding process parameters of 1420 aluminum alloy are electron beam flow of 10 mA, welding speed of 800 mm/min. Under the optimal process, the weld zone after heat treatment has tiny nano AlrLi phase, spherical Al3Zr phase and short rod Al2MgLi phase, the tensile strength of welded joint increass after heat treatment, while the yield strength and elongation decrease.
出处
《热加工工艺》
CSCD
北大核心
2016年第23期193-197,共5页
Hot Working Technology
