某薄壁钛合金贮箱焊接工艺性分析

Welding Technology Analysis of A Thin Wall Titanium Alloy Tank

通过ANSYS有限元软件模拟钛合金隔膜贮箱的应力云图,结合破裂样件的宏观形貌和微观组织分析,探讨了贮箱低爆失效机理,提出了相应的改进措施,并验证了措施的可行性。结果表明,贮箱破裂断口源于手工氩弧焊起弧与收弧的重叠区,过大的焊接热输入量加剧了焊缝脆性倾向,形成了粗大的魏氏组织,导致贮箱焊缝金属综合力学性能下降;增加壁厚对贮箱承压能力的提高并不显著。采用电子束焊接工艺,降低焊接热量输入量,能显著提高贮箱的承压能力,贮箱的爆破压力达到10MPa,能满足产品的使用要求。

The stress nephogram of a titanium alloy diaphragm tank was simulated by ANSYS finite element software.Combined with the macro-morphology and microstructure analysis of the fracture sample,the low explosion failure mechanism of the tank was discussed,corresponding improvement measures were put forward,and the feasibility of the measures was verified.The results show that the fracture source of the tank originates from the overlapping area between the art starting position and the stopping position of manual argon arc welding.Excessive welding heat input intensifies the tendency of weld brittleness and forms coarse widmanstatten structure,which leads to the decline of comprehensive mechanical properties of the tank weld metal.The pressure bearing capacity of the tank is not significantly improved by increasing the wall thickness.By using electron beam welding technology,the welding heat input is reduced,and the pressure bearing capacity of the tank is significantly improved.The burst pressure of the tank reaches 10 MPa,which can meet the use requirements of the product.