以铌为中间层的钛与低碳钢的电阻点焊

Resistance Spot Welding Between Titanium and Mild Steel with an Insert of Nb

以0.1mm厚的铌箔为中间层对钛与低碳钢Q235进行了点焊,观察了接头熔核区域的显微组织特征,探讨了焊接电流对接头熔核直径和抗剪力的影响。结果表明,焊接电流大于8 kA时,中间层铌在焊接中发生溶断,接头熔核区域组织主要由Fe-Ti金属间化合物构成;铌不发生溶断时,接头熔核区域组织主要由Fe-Nb化合物与固溶体组成。接头抗剪力随焊接电流的增大呈先增大后减小的变化趋势,焊接电流为7 kA时接头抗剪力最大,约为4.7 kN。

Titanium and Q235 mild steel sheets were welded by resistance spot welding with an insert of 100 μm thick niobium foil.The interfacial microstructure characteristics were analyzed;the effects of welding current on the nugget diameter and tensile shear load of the joint were studied.The results reveal that the niobium foil disconnects during spot welding when the welding current is greater than 8 kA;the nugget is mainly composed of Fe-Ti intermetallic compounds in the case;and that the nugget is mainly composed of Fe-Nb compounds and some solid solution when the niobium foil does not disconnect during spot welding.The tensile shear load of the joint increases and then decreases with the increase of welding current.A maximum tensile shear load of 4.7 kN is obtained at a welding current of 7 kA.