This research article investigated the hot corrosion behaviour of the pulsed current gas tungsten arc (PCGTA) welded Fe-based alloy A-286. PCGTA welding is employed to obtain a similar joint of 6 mm plates of A-286 alloy using ER-320LR filler material. A high-velocity oxy-fuel (HVOF) coating is carried out to deposit Cr₃C₂-25%NiCr and Ni-20%Cr coating on the PCGTA weldments. The microstructure and elemental analysis of the surface and cross-sections of the coatings were examined by Scanning electron microscope (SEM) combined with energy dispersive spectroscopy (EDS). Hot corrosion study is carried out on bare, and HVOF coated PCGTA weldments in Na₂SO₄-7.5%NaVO₃-5%NaCl environment at 850 C. The corrosion frate of the weldments was determined by thermogravimetric analysis. The reaction products present in the weldments were characterized by SEM and x-ray diffraction (XRD) analysis. Depths of corrosion attack and elemental distribution on the weldments at cross-section are analyzed using EDS with the x-ray mapping technique. The Cr₃C₂-25%NiCr coated weldment exhibits the superior corrosion resistance than bare and the Ni-20%Cr coating due to the development of chromium oxide (Cr₂O₃) scales. The chromium carbide coating has a reduced weight gain of 56% and 25% compared to uncoated, and Ni-20%Cr coated specimens.

本文研究了脉冲电流钨极氩弧焊（PCGTA）焊接的铁基合金A-286的热腐蚀行为。PCGTA焊接用于使用ER-320LR填充材料获得类似的6毫米A-286合金板接头。进行高速氧燃料（HVOF）涂层，以在PCGTA焊件上沉积Cr ₃ C ₂ -25％NiCr和Ni-20％Cr涂层。涂层的表面和横截面的显微结构和元素分析通过扫描电子显微镜（SEM）结合能量色散光谱（EDS）进行检查。在Na ₂ SO ₄ -7.5％NaVO _3中对裸露和HVOF涂层PCGTA焊件进行热腐蚀研究在850°C下为-5％NaCl环境。通过热重分析确定焊件的腐蚀速率。焊件中存在的反应产物通过SEM和X射线衍射（XRD）分析进行了表征。使用X射线映射技术的EDS分析横截面的腐蚀腐蚀深度和焊件上的元素分布。Cr ₃ C ₂ -25％NiCr涂层的焊接件比裸露的涂层和Ni-20％Cr涂层具有更好的耐腐蚀性，这归因于氧化铬（Cr ₂ O ₃）氧化皮的发展。与未涂层和Ni-20％Cr涂层的样品相比，碳化铬涂层的增重减少了56％和25％。