摘要
针对水轮机0Cr13Ni5Mo马氏体不锈钢叶片的空蚀失效问题,研究了RMD650合金焊丝电弧堆焊工艺修复空蚀坑的修复效果。采用工作电压18.8 V、工作电流240 A、焊枪移动速度10 mm/s、送丝速度4.5 m/min等堆焊工艺参数,在0Cr13Ni5Mo马氏体不锈钢板上制备单层和15层堆焊层,研究了堆焊组织的力学性能及抗空蚀性能。实验结果表明:单层堆焊层原始奥氏体晶粒为柱状,15层堆焊层原始奥氏体晶粒为等轴状,而15层堆焊过程中,冷却速度只会影响原始奥氏体晶粒形貌,几乎不会影响最终的马氏体形成及其尺寸。显微硬度测试及核平均取向差(kernel average misorientation,KAM)分析结果表明:15层堆焊层硬度变化的主要原因是位错密度的变化。空蚀实验结果表明:具有更高硬度的第15层堆焊层的抗空蚀性能更优。
To address the cavitation failure of 0Cr13Ni5Mo martensitic stainless steel blades in water turbines,the repair effectiveness of RMD650 alloy wire arc welding for cavitation pit restoration was investigated.The welding parameters of the study included a working voltage of 18.8 V,a working current of 240 A,a welding torch travel speed of 10 mm/s,and a wire feed speed of 4.5 m/min.Singlelayer and 15-layer weld cladding were prepared on 0Cr13Ni5Mo martensitic stainless steel plates to study the mechanical properties and cavitation resistance.The results show that the 15-layer cladding process transforms the columnar original austenite grains formed in the single-layer cladding into equia-xed grains,and during the 15-layer cladding process,the cooling rate only affects the morphology of the original austenite grains,with minimal impact on the final martensite formation and its size.Micro hardness testing and KAM analysis results indicate that the hardness variation during the 15-layer cladding process is primarily due to changes in dislocation density.The Cavitation tests revealed that the 15th layer,with higher hardness,demonstrats superior cavitation resistance.
作者
胡栋
兰箭
HU Dong;LAN Jian(Wuhan Univ.of Technology,Wuhan 430070,China)
出处
《海军工程大学学报》
2025年第2期34-39,共6页
Journal of Naval University of Engineering
基金
国家自然科学基金资助项目(51975439)。
关键词
RMD650焊丝
电弧堆焊
硬度
空蚀
RMD650 welding wire
arc cladding
hardness
cavitation erosion
