6061-T6铝合金微搅拌摩擦焊工艺

以0.8 mm厚6061铝合金微搅拌摩擦焊对接过程为研究对象，采用专用搅拌工具，通过温度场模拟进行工艺参数预选，研究了无倾角微搅拌摩擦焊的工艺参数对接头力学性能的影响，确定了与所设计微搅拌工具相匹配的工艺参数窗口；并采用光学显微镜、SEM扫描电镜对接头的微观组织、断口的形貌进行观察. 结果表明，在焊接速度为300 mm/min、转速14 000 ~ 24 000 r/min时，可以获得力学性能优越的焊接接头，抗拉强度均可达母材的70%以上；微搅拌摩擦焊缝微观组织的热影响区与传统搅拌摩擦焊相比，仅部分晶粒发生长大，仍有部分晶粒与基体保持一致无明显变化.

Micro friction stir welding technology of 6061-T6 aluminum alloys

Taking the butt welding process of 0.8 mm 6061 aluminum alloys micro-friction stir welding as the research object, using special tool and simulating the temperature field to pre-select the process parameters, their mechanical properties for different rotational speeds were compared by tensile test and the best welding parameter matching for the total were confirmed. The microstructures were studied by optical microscope and scanning electron microscopy. It is shown that the welded joints with superior mechanical properties can be got when the traversing speed reaches 300 mm/min and the rotational speed reaches 14 000 ~ 24 000 r/min, the tensile strength of which is above 70% of base metal. Compared with traditional friction stir welding, the HAZ of micro-structure of micro-friction stir welding seam only partially grew up, but some grains remained the same as the matrix without obvious change.