论文部分内容阅读
TC4因其优良的力学性能和工艺性能而被广泛地使用,但是由于在焊缝及近缝区的塑性压缩变形导致焊接件中存在绝对值较大的焊接纵向残余压应力和焊接变形,其根本原因在于纵向焊接残余压应力超过了TC4薄板件的临界失稳应力。为了减少焊接变形及其所导致的附加弯矩,采用随焊冲击旋转挤压的方式对焊缝及近缝区进行塑性延展。其中跟随焊接热源移动的外加载荷将对焊接过程中的应力应变过程产生影响。采用有限元方法分析局部外加载荷对焊接残余应力及焊接瞬态应力应变的演化过程的作用,分析结果说明在外加载荷的作用下产生了塑性延展,降低了焊接残余应力,从根本上消除了导致焊接变形的因素。
TC4 is widely used because of its excellent mechanical properties and process properties. However, due to the plastic compressive deformation in the weld and the near-seam area, the weld longitudinal compressive residual stress and welding deformation with large absolute value exist. The reason is that the longitudinal compressive residual stress exceeds the critical buckling stress of TC4 sheet. In order to reduce the welding deformation and the additional bending moment caused by it, the weld seam and the near-seam area are ductilely stretched by means of swirling and extrusion with the welding impact. Among them, the applied load following the welding heat source will have an impact on the stress-strain process in the welding process. The finite element method was used to analyze the effect of local applied load on the welding residual stress and the evolution of welding transient stress-strain. The results show that the plastic extension is generated under the applied load and the welding residual stress is reduced, Welding deformation factors.