电子束环焊缝水腐蚀后蓝色环产生机理及防止措施FORMING.PDFVIP

CNIC-01574 NFE-0016 电子束环焊缝水腐蚀后蓝色环 产生机理及防止措施 FORMING MECHANISM AND AVOIDING MEASURES OF WATER BLUE-RING ON ELCTRONIC BEAM WELDING SAMPLE AFTER WATER CORROSION (In Chinese) 中 国 核 情 报 中 心 China Nuclear Information Centre CNIC-01574 NFE-0016 电子束环焊缝水腐蚀后蓝色环 产生机理及防止措施 任德芳 罗先典 童慎修 郭旭林 彭海清 (宜宾核燃料元件厂，644000) 摘 要 俄罗斯制大容器电子束焊机焊接的AFA 2G 燃料棒随炉试样按 ASTM G2 水腐蚀后出现“蓝色环”。描述了“蓝色环”的特征， 对其形貌、化学成分、金相组织进行了检测和大量的条件试验。结 果表明“蓝色环”产生的机理是：焊接时产生的金属蒸气和夹头、 枪体等金属蒸气涂层因散焦电子、二次电子的轰击产生的溅射物在 水冷夹头的强制冷却下，沉积在焊缝热影响区与基体之间，这些沉 积物水腐蚀后形成一种蓝色腐蚀产物，并呈环状。消除方法是将水 冷夹头靠近焊缝的一端与燃料棒接触的边倒一小角，以及加强焊接 室的清洁度。 1 Forming Mechanism and Avoiding Measures of Blue-Ring on Electronic Beam Welding Sample after Water Corrosion (In Chinese) REN Defang LUO Xiandian TONG Shenxiu GUO Xulin PENG Haiqing (Yinbin Nuclear Fuel Element Plant, 644000) ABSTRACT After water corrosion in compliance with ASTM G2, the blue ring appears on the nuclear fuel rod samples of AFA 2G welded by using a Big Chamber Electron Beam Welder made in Russia. The characteristics, appearance, chemical composition, microstructure of “blue ring” and some condition test are described. The mechanism of forming blue ring may be depicted as following: welding metal vapor and the splash produced by secondary and scatter electrons on metal clamp and gun body deposit in the area between HAZ and substrate because of the water cooling down effects on the clamp; these deposits, after water corrosion, ap