基于Incoloy800H钨极氩弧焊接头组织及其性能分析

发布时间：2018-06-10 09:42

本文选题：核电 + H合金　；参考：《稀有金属材料与工程》2015年11期

【摘要】：在2 mm厚800H合金钨极氩弧焊试验的基础上,研究焊接接头的微观组织和析出相成分,并分析焊接接头的力学性能和抗晶间腐蚀性能,观察拉伸断口和晶间腐蚀试样的形貌。结果表明:焊缝组织为柱状晶和等轴晶,热影响区晶粒明显长大,焊接接头中有少量的TiN和富Cr相(Fe,Cr)_(23)C_6析出相存在;母材、热影响区和焊缝的HV硬度分别为1730、1526和1590 MPa;室温抗拉强度和延伸率分别为565.0 MPa、31.8%,均超过ASME标准关于800H合金规定值(450.0 MPa和30.0%),拉伸断裂为韧性断裂;焊接接头高温(650℃)抗拉强度和延伸率分别为394.5 MPa、15.5%,其断口是混合型断口;较接头组织,母材腐蚀更为严重,表面晶界开裂并伴有少量且尺寸较小的腐蚀坑,基体中TiN缺陷处易引起点蚀。
[Abstract]:On the basis of TIG welding test of 800H alloy with thickness of 2 mm, the microstructure and precipitated phase composition of welded joints were studied. The mechanical properties and intergranular corrosion resistance of welded joints were analyzed, and the morphology of tensile fracture and intergranular corrosion specimens were observed. The results show that the microstructure of the weld is columnar and equiaxed, and the grains in the HAZ grow up obviously. There are a few precipitated phases of tin and Cr-rich phase in the welded joints. The HV hardness of the HAZ and the weld seam were 1 730m 1526 and 1590 MPA, respectively, and the tensile strength and elongation at room temperature were 565.0 MPA and 31.8 MPA respectively, which exceeded the specified values of 800H alloy in the ASME standard (450.0 MPA and 30.0 MPA, respectively), and the tensile fracture was ductile fracture. The tensile strength and elongation of the welded joint are 394.5 MPA ~ (15. 5) respectively. The fracture surface is a mixed fracture, and the base metal corrosion is more serious than the joint structure, and the surface grain boundary is cracked with a small number of corrosion pits with small size. Tin defects in the matrix are prone to pitting corrosion.
【作者单位】：江苏大学;江苏银环精密钢管股份有限公司;北京赛福斯特技术有限公司中国搅拌摩擦焊中心;
【基金】：“十二五”国家高技术研究发展计划(“863”计划)重大资助项目(2012AA03A501) 江苏大学高级专业人才基金资助项目(12JDG066) 省级重点实验室开放课题资助项目(kjsmcx1004)
【分类号】：TG444.74

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