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利用电子显微镜对不同材料组合和焊接条件下，奥氏体不锈钢焊缝中形变挛晶的形态进行了观察。实验发现焊缝中形变孪晶的数量和形态与接头的拘束条件有关。在全拘束接头一，孪晶的数量最多，还会出现多次孪晶。随拘束程度的下降，孪晶数量减少。在无拘束接头中，几乎看不到孪晶。这些形变孪晶是由于在奥氏体钢焊缝冷却过程中，结晶凝固和δ－铁素体向奥氏体的相转变，导致焊缝体积缩小而快速引入的拉伸切应力产生的。
Electron microscopy was used to observe the morphologies of deformed twin crystals in the austenitic stainless steel weld under different material combinations and welding conditions. The experiment found that the number and shape of deformation twins in the weld are related to the constraints of the joints. In the full restraint connector, the largest number of twins, there will be multiple twins. As the degree of restraint declines, the number of twins decreases. In unrestrained joints, almost no twins can be seen. These deformation twins are due to the rapid introduction of tensile shear stress resulting from the shrinkage of the weld volume due to the crystalline solidification and phase transformation of δ-ferrite to austenite during the cooling of the austenitic steel weld.