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控制焊缝凝固时所受的拉伸应变是防止焊缝凝固裂纹产生的有效方法之一。利用数值模拟和试验研究了施加辅助冷、热源改变焊接温度场，减少焊缝所受的拉伸应变的规律以及施加冷、热源后对焊接接头组织和硬度的影响。研究表明：辅助热源的能量密度及施加位置合适时，可以有效地降低拉伸应变，防止凝固裂纹产生；施加辅助冷源也可以降低焊缝所受的拉伸应变，但效果不如辅助热源显著；在本试验条件下施加辅助冷、热源对焊接接头的组织影响不大，对硬度也无明显的影响。
It is one of the effective methods to prevent the occurrence of weld solidification cracks when controlling the tensile strain of the weld during solidification. The effects of applying auxiliary cold and heat sources on changing the welding temperature field, reducing the tensile strain on the weld, and the effect of applying cold and heat sources on the microstructure and hardness of the welded joints were studied by numerical simulation and experiments. The results show that the auxiliary heat source can reduce the tensile strain and prevent the solidification crack when the energy density and position of the auxiliary heat source are suitable. The auxiliary cold source can also reduce the tensile strain of the weld, but the effect is not as good as the auxiliary heat source. Auxiliary cold and heat sources exert little influence on the microstructure of the welded joint under the test conditions and have no obvious effect on the hardness.