铁基合金堆焊层裂纹原因分析及工艺改进

铁基合金堆焊层裂纹原因分析及工艺改进 Analysis and improvement of cracking in ironbase alloy hardfacing layer 朱伟 ZHU Wei 1 first-author 高俊根 GAO Jungen 1 孔永红 KONG Yong hong 1 朱建雄 ZHU Jianxiong 1 吴金龙 WU Jinlong 1 朱勃 ZHU Bo 1 张玉庆 ZHANG Yuqing 1 中广核工程有限公司 中广核工程有限公司 Shenzhen China Nuclear Power Design Co.,Ltd. Shenzhen China Nuclear Power Design Co.,Ltd. 某核电项目现场在安装和调试工作结束后,发现某国外阀门厂制造的批量阀门的阀座、阀瓣等零件的铁基合金堆焊表面有裂纹和开裂的情况。在对典型裂纹零件进行系统性的分析和检测后,确定了堆焊层裂纹原因为:铁基合金堆焊及后续加工过程中易产生微观缺陷(如树枝状空腔)、加工毛刺、尖锐缺口等裂纹源。通过优化堆焊零件结构和堆焊工艺(增加预热或提高预热温度、焊后热处理等)后,能够有效降低焊缝中的残余应力,现场反馈改进效果良好,为后续核电项目硬质合金堆焊零件制造、加工和检验提供了借鉴。 After installation and commissioning, cracks were found in the iron-base alloy hard-faced sealing surface and the iron-base alloy hard-faced guide surface of bulk imported valve parts from a foreign valve manufacturer. After systematic analysis and testing of the typical crack-containing parts, the root cause of the weld cracks was determined and summarized. After optimizing the structure of the hard face layer and the hard-facing progress, the replacement valve parts have been proven have better crack resistance and anti-expansion ability. Above all, this provides an engineering reference for the iron-based alloy welding in nuclear power equipment applications. 阀门 铁基合金 堆焊 高温失塑裂纹 残余应力 valve iron-base alloy hardfacing high temperature crack residual stress TG455;TM623 2022-03-08 11 51