Soleimani Ahmad, Akbari Mohammad, Karimipour Arash, Meghdadi Isfahani Amir Homayoon, Nosouhi Reza
Department of Mechanical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran.
Aerospace and Energy Conversion Research Center, Najafabad Branch, Islamic Azad University, Najafabad, Iran.
Heliyon. 2024 Feb 7;10(4):e26010. doi: 10.1016/j.heliyon.2024.e26010. eCollection 2024 Feb 29.
This study focused on dissimilar welding characterization of Inconel 600 and duplex 2205 stainless steel using central composite design (CCD) of experiments the response surface methodology (RSM). This study determined the effect of laser welding parameters and the reactions of the temperature field on the melt pool, the mechanical characteristics of the weld joint, and the geometry of the melt pool. According to the ANOVA results, the power of laser and focal distance were found to be the most influential factors on the temperature of both Inconel 600 and duplex stainless steel. The weld joint's tensile strength and elongation were significantly influenced by laser power and focal distance. Increasing the laser power from 250 to 450 W raised the tensile strength from 250 to 550 MPa. The Mo rich phases formed at the inter-dendritic region according to the EDS phase analysis results in loss of ductility and the resultant tensile strength of the samples failure from the fusion zone adjacent to the duplex stainless steel. At high laser power levels, the samples fractured from fusion zone while at lower laser powers below 350 W, the samples fractured from the HAZ and the areas adjacent to the duplex steel fusion line. The micro-hardness value of the weld joint at different laser power of 525 W and 375 W was increased to the maximum values of 370 and 325 HV, respectively from the fusion line of Inconel 600 to the center of the fusion zone. Further, molten pool microstructure of the dissimilar joint zone was mainly composed of a cellular and columnar dendritic structure Variations in melt flow, temperature gradient and solidification rate from the molten scan line to the weld center clearly changed the grain growth and the resultant microstructure in different areas of the fusion zone. By transferring the laser light to the center of the Inconel 600 and duplex stainless steel joint, the molten pool depth was increased from 0.2 to 1.5 mm.
本研究采用实验的中心复合设计（CCD）和响应面方法（RSM），聚焦于因科镍合金600与双相2205不锈钢的异种焊接特性。本研究确定了激光焊接参数的影响以及温度场对熔池、焊接接头力学性能和熔池几何形状的作用。根据方差分析结果，发现激光功率和焦距是对因科镍合金600和双相不锈钢温度最具影响的因素。激光功率和焦距对焊接接头的抗拉强度和伸长率有显著影响。将激光功率从250 W提高到450 W，抗拉强度从250 MPa提高到550 MPa。根据能谱相分析结果，在枝晶间区域形成的富钼相导致延性丧失，以及双相不锈钢相邻熔合区样品的抗拉强度失效。在高激光功率水平下，样品从熔合区断裂，而在低于350 W的低激光功率下，样品从热影响区和双相钢熔合线附近区域断裂。在525 W和375 W不同激光功率下，焊接接头的显微硬度值分别从因科镍合金600的熔合线到熔合区中心增加到最大值370 HV和325 HV。此外，异种接头区的熔池微观结构主要由胞状和柱状树枝晶结构组成。从熔池扫描线到焊缝中心的熔体流动、温度梯度和凝固速率的变化明显改变了熔合区不同区域的晶粒生长和最终微观结构。通过将激光束转移到因科镍合金600和双相不锈钢接头的中心，熔池深度从0.2 mm增加到1.5 mm。
