Rani Kasireddy Usha, Kumar Rajiv, Mahapatra Manas M, Mulik Rahul S, Świerczyńska Aleksandra, Fydrych Dariusz, Pandey Chandan
School of Mechanical Sciences, Indian Institute of Technology, Bhubaneswar 752050, India.
Mechanical and Industrial Engineering Department, Indian Institute of Technology Roorkee, Roorkee 247667, India.
Materials (Basel). 2022 Oct 12;15(20):7094. doi: 10.3390/ma15207094.
Wire arc additive manufacturing (WAAM) is an additive manufacturing process based on the arc welding process in which wire is melted by an electric arc and deposited layer by layer. Due to the cost and rate benefits over powder-based additive manufacturing technologies and other alternative heat sources such as laser and electron beams, the process is currently receiving much attention in the industrial production sector. The gas metal arc welded (GMAW) based WAAM process provides a higher deposition rate than other methods, making it suitable for additive manufacturing. The fabrication of mild steel (G3Si1), austenitic stainless steel (SS304), and a bimetallic sample of both materials were completed successfully using the GMAW based WAAM process. The microstructure characterization of the developed sample was conducted using optical and scanning electron microscopes. The interface reveals two discrete zones of mild steel and SS304 deposits without any weld defects. The hardness profile indicates a drastic increase in hardness near the interface, which is attributed to chromium migration from the SS304. The toughness of the sample was tested based on the Charpy Impact (ASTM D6110) test. The test reveals isotropy in both directions. The tensile strength of samples deposited by the WAAM technique measured slightly higher than the standard values of weld filament. The deep hole drilling (DHD) method was used to measure the residual stresses, and it was determined that the stresses are compressive in the mild steel portion and tensile in austenitic stainless steel portion, and that they vary throughout the thickness due to variation in the cooling rate at the inner and outer surfaces.
电弧增材制造（WAAM）是一种基于电弧焊接工艺的增材制造工艺，在该工艺中，金属丝通过电弧熔化并逐层沉积。由于与基于粉末的增材制造技术以及激光和电子束等其他替代热源相比，具有成本和速率优势，该工艺目前在工业生产领域备受关注。基于气体保护金属电弧焊（GMAW）的WAAM工艺比其他方法具有更高的沉积速率，使其适用于增材制造。使用基于GMAW的WAAM工艺成功完成了低碳钢（G3Si1）、奥氏体不锈钢（SS304）以及这两种材料的双金属样品的制造。使用光学显微镜和扫描电子显微镜对所制备样品的微观结构进行了表征。界面显示出低碳钢和SS304沉积物的两个离散区域，没有任何焊接缺陷。硬度分布表明界面附近硬度急剧增加，这归因于铬从SS304的迁移。基于夏比冲击（ASTM D6110）试验对样品的韧性进行了测试。试验表明在两个方向上均具有各向同性。通过WAAM技术沉积的样品的拉伸强度测得略高于焊接丝的标准值。采用深孔钻削（DHD）方法测量残余应力，结果表明低碳钢部分的应力为压缩应力，奥氏体不锈钢部分的应力为拉伸应力，并且由于内外表面冷却速率的变化，应力在整个厚度上有所不同。
