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用予裂纹悬臂梁试样研究了 Hy-100和 Hy-130钢的基体金属和焊缝在海水中阴极保护电位为-1.0伏(相对于 Ag/AgCl)时的抗应力腐蚀开裂(SCC)能力。本研究的目的是鉴别对决定抗SCC 能力有重要影响的冶金和焊接因素,并确定使 Hy 钢敷焊焊缝金属获得与轧制基体板材相同的抗 SCC 能力的可能性。对金属极气体保护焊(GMA)、金属极电弧焊(SMA)和钨极气体保护电弧焊(GTA)制成的焊缝金属以及对轧制板材基体作了机械性能、金相和应力腐蚀开裂试验。发现强度水平是控制Hy-100和 Hy-130钢基体金属和焊缝金属在海水中的 SCC 界限值水平的支配因素。在决定 Hy 钢焊缝金属的抗 SCC 能力方面,由焊接工艺和参数确定的显微组织比化学成分更重要。当采用低敷焊速度的 GTA 焊接工艺时其 SCC 的界限值水平可与轧制板材基体相当。对焊缝金属显微组织可进行有效的再加热细化和回火的焊缝参数对 Hy-130钢焊缝金属获得最大的抗 SCC 能力显得很重要,而强度相对较低的 Hy-100钢焊缝1英寸(25毫米)厚的 SCC试样则有很高的抗 SCC 能力。
The resistance to SCC of Hy-100 and Hy-130 steels and weld metal in cathodic protection potential of -1.0 V (relative to Ag / AgCl) in seawater was investigated using pre-cracked cantilever specimens . The purpose of this study was to identify the metallurgical and welding factors that have a significant impact on the ability to determine SCC resistance and to determine the potential for Hy-coated wire weld metal to achieve the same SCC-resistance as rolled base plate. Metallic GMA, SMA and GTA weld metal as well as the rolling plate substrate made of mechanical properties, metallographic and stress corrosion cracking test. The strength level was found to be the dominant factor controlling the SCC threshold level of Hy-100 and Hy-130 steel base metal and weld metal in seawater. The microstructure determined by the welding process and parameters is more important than the chemical composition in determining the resistance to SCC of Hy-steel weld metal. The SCC threshold level can be comparable to a rolled plate substrate when using a GTA welding process with a low flux rate. Weld seam metal microstructure for effective reheat refinement and tempering of the weld parameters Hy-130 steel weld metal to obtain the maximum resistance to SCC capacity is very important, while the strength of the relatively low Hy-100 steel Weld 1 inch (25 mm) thick SCC samples have very high resistance to SCC.