(1. 合肥工業(yè)大學 材料科學與工程學院，合肥 230009；
2. 安徽省電力科學研究院，合肥 230601；
3. 合肥津利能源科技發(fā)展有限公司，合肥 230601)
摘 要: 采用鎢極氬弧焊(GTAW)技術，采用ERNiCr-3和ERNiCrMo-3兩種鎳基焊絲實施T92/Super304H異種鋼焊接，并對接頭的顯微組織結構及力學性能進行測試分析。結果表明：T92側熱影響區(qū)(HAZ) 中粗晶區(qū)析出大量的第二相顆粒，細晶區(qū)則為細小的索氏體組織；Super304H側 HAZ奧氏體晶粒長大，晶界析出明顯；ERNiCr-3焊接的焊縫組織呈胞狀結構，晶粒粗大；ERNiCrMo-3焊接的焊縫組織呈柱狀晶組織特征。ERNiCrMo-3焊接的接頭強度、塑性及硬度較大，拉伸斷裂位于Super304H母材；而ERNiCr-3焊接的接頭強度、硬度較低，但沖擊韌性較高，拉伸斷裂位于焊縫。
關鍵字: T92鋼；Super304H鋼；異種鋼焊接接頭；微觀組織；力學性能
（1. School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China;
2. Anhui Institute of Electric Power Science, Hefei 230601, China;
3. Hefei Jinli Power S）
Abstract:T92/Super304H dissimilar steel joints were produced through gas tungsten arc welding (GTAW) technique, using two Ni-based welding wires of ERNiCr-3 and ERNiCrMo-3, respectively. The microstructures and mechanical properties of the joints were then studied. The results show that in the heat-affected zone (HAZ) of the T92 side, lots of second-phase particles precipitate along the grain boundaries and inside the grains of the prior austenites. The fine grain zone of the T92 side HAZ is of a sorbite structure. In the Super304H side HAZ, the austenitic grains grow up rapidly with lots of precipitates along the grain boundaries. The ERNiCr-3 welding seam in the joint is of a coarse cellular structure. Comparatively, the ERNiCrMo-3 welding seam is of dense columnar grains. The ERNiCrMo-3 welded joints have higher strength, ductility and hardness, however, the ERNiCr-3 welded joints have a higher impact toughness value. Moreover, the tensile fracture of the formers takes place in the Super304H base metal, while that of the latters happens in the welding seam.
Key words: T92 steel; Super304H steel; dissimilar steel weld joint; microstructure; mechanical properties
