焊接残余应力对矩形薄板力学性能影响

Analysis of effect of welding residual stress on the mechanical properties of rectangular thin plates

运用ANSYS有限元软件,根据金属材料微观晶胞结构,建立了面心立方结构的二维金属多晶胞模型;利用生死单元技术和该模型,对堆焊矩形薄板的焊接过程进行了模拟,得出其残余应力场分布;探讨了残余应力对堆焊矩形薄板的固有频率的影响;研究了残余应力对堆焊矩形薄板内应力分布及大小的影响;结果表明,在有残余应力存在的情况下,矩形薄板的各阶固有频率增加;且高阶固有频率比低阶固有频率受残余应力影响更大;残余应力对矩形薄板内应力分布影响不大,但对矩形薄板内晶胞中的原子上应力和原子间金属键上的应力影响比较大。

Acco rding to the microcosmic crystal structure of metal materials, with the finite element software ANSYS,the two-dimensional metallic multiple unit cell model of face-centered cubic structure is established; Based on the element birth and death technology and the above-mentioned model,the surfacing process of the rectangular thin plate is simulated to obtain the residual stress field distribution. The influence of residual stress on the inherent frequency of surfacing of rectangular thin plate is discussed,and the influence of residual stress on the final interior stress distribution and size of surfacing of rectangular thin plate under the action of external force is researched. The result shows that when the residual stress exists,each order inherent frequency of rectangular thin plate increases. And the inherent frequency of higher order gets a greater influence than that of lower order by residual stress. The residual stress has a little effect on the interior stress distribution of rectangular thin plate,but has relatively large effect on atomic stress and stress on the metallic bond between atoms of rectangular thin plate.