TC4薄板随焊旋转挤压工艺

Welding TC4 thin plates by revolution pressing in welding process

薄板钛合金由于在焊后存在较大的残余压应力,使得其易发生失稳变形.采用随焊旋转挤压方式,对焊缝高温部位进行塑性延展,减少焊接时所发生的塑性收缩量,降低残余压应力的值,从而降低焊接变形量.采用拉伸试验、拉伸断口SEM分析和焊后薄板的变形挠度的测量等试验.结果表明,随焊旋转挤压焊件的变形挠度可以下降到常规焊件挠度的2/3,并且随着加载应力的增加,变形的挠度可以进一步下降.说明在焊接过程中采用随焊旋转挤压方式控制薄板TC4失稳变形是可行的.

The welded residual compression stress which is larger than the critical compression stress will cause buckling distortion of TC4 thin plate after normal welding.In order to decrease buckling distortion,the method of revolution pressing in welding process was utilized to gain plastic extension in the high temperature zone of the welding bead.The residual stress can be reduced by compensating the plastic shrinkage in the high temperature zone.Tensile test,SEM analysis of the tensile testing specimen and measurement of the joints distortion after welding were carried out.The results showed that the deflection could be decreased to two thirds of the original deflection after the high temperature zone metal received revolution pressing.With increased pressing loading,the deflection reduced.In a word,the method of revolution pressing in welding process is feasible to control the deflection of TC4 thin plate weldment.