高强钢振动焊接工艺参数的优化

Optimization of GMA welding process under vibration of high strength steel

在WQ960高强钢GMAW焊接过程中施加机械振动,焊接过程中通过改变焊接电流、振动频率和振动振幅实现随焊随振.为了确定高强钢振动焊接的最佳工艺参数,引入正交试验方法,对各个参数下的焊接接头的微观组织、拉伸性能和冲击性能进行分析,确定最佳参数,并探究振动参数和焊接参数共同作用下高强钢焊接接头的组织性能演变规律及机理.结果表明,最佳振动焊接工艺参数为:焊接电流220 A,振动频率50 Hz,振动振幅0.5 mm;此时焊接接头的力学性能分别为:抗拉强度为875 MPa,冲击吸收功为70 J.这是因为振动可以细化晶粒,减少先共析铁素体的析出,进而使焊接接头的力学性能提高.

The WQ960 high strength steel was welded by GMAW welding under mechanical vibration. The welding current,vibration frequency and amplitude were changed to achieve welding with vibration during the welding process. In order to determine the optimal vibration welding process parameters of high strength steel,the orthogonal test method was used. The microstructure,tensile and impact properties of the welded joint at different parameters were analyzed to determine the optimal parameters. The relationship between vibration parameters and welding parameters and microstructure and properties of welded joints were researched,the action mechanism was also discussed. The results showthat the optimal properties of welded joints are obtained at welding current I = 220 A,frequency f = 50 Hz,and vibration amplitude A = 0. 5 mm,whicharetensile strength Rm=875 MPa,the impact energy AKv= 70 J. The vibrations can refine grains,reduce eutectoid ferrite precipitation,increase the number of needle ferrite,thereby the mechanical properties of welded joints can be improved.