SPCC冷轧钢光纤激光拼焊工艺及焊缝组织研究

Fiber laser welding of SPCC steel plate and microstructures of weld

采用数控光纤激光焊接机,对1.2 mm+2.5 mm SPCC冷轧板进行不等厚拼焊,研究了焦点位置、激光功率与焊接速度、保护气体等工艺参数对焊缝形成、熔深的影响,优化工艺参数可以获得深而窄、均匀美观的焊缝;焊后对焊接接头进行金相分析和拉伸、杯突试验。结果表明,热影响区组织细小、性能优良,焊缝冷却后出现错位马氏体和针状铁素体组织,提高了焊缝的硬度和韧性,拉伸断裂位置位于母材,表明焊接接头的力学性能优于母材。

The CNC fiber laser welding machines was used to weld 1.2 mm +2.5 mm SPCC cold rolled plate.The effects of focus position,laser power,welding speed and protective gas on the weld shape and penetration depth were studied.The results show that the narrow weld with deep penetration and uniform appearance can be obtained with proper process parameters.The heat affect zone was composed of fine martensite and acicular ferrite,both of then show the excellent properties and improve the hardness and toughness of the weld.Tensile test shows that the fracture occurs at the base metal,which proves that the mechanical properties of the joint are better than that of the base metal.