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研究了预热对Ｔｉ－２３Ａｌ－１４Ｎｂ－３Ｖ合金焊接性，特别是对消除氩弧焊冷裂纹的作用以及对接头显微组织和力学性能的影响。结果表明，焊前预热可有效降低该合金的冷裂倾向。经预热处理后，焊缝区的结晶层状线消失，热影响区的硬度峰得到缓和，整个焊缝的显微硬度分布趋于均匀，但焊缝区的枝晶发生粗化，热影响区有所扩大。焊件接头的拉伸试验表明，预热可使焊缝区的接头强度系数增加，但无论预热与否，接头强度均低于母材强度，且不显示宏观塑性。
The effect of preheating on the weldability of Ti-23Al-14Nb-3V alloy, especially on eliminating the cold crack of argon arc welding, as well as on the microstructure and mechanical properties of the joint were studied. The results show that preheating before welding can effectively reduce the cold cracking tendency of the alloy. After the preheating treatment, the crystalline stratified line in the weld zone disappears and the hardness peak in the heat affected zone is alleviated. The microhardness distribution of the whole weld tends to be uniform, but the dendrites in the weld zone are coarsened and the thermal influence The area has expanded. Tensile tests of weldment joints show that preheating can increase the joint strength coefficient of the weld zone, but the joint strength is lower than the base metal strength and does not show the macroscopic plasticity whether preheating or not.