摘要
通过改变不同焊接参数，使用手工钨极氩弧焊在奥氏体不锈钢304H表面进行司太立6钴基合金堆焊，并对所得的堆焊层熔敷金属进行化学成分、截面显微硬度、洛氏硬度、晶间腐蚀和显微组织等测试分析．结果表明：电特性参数及焊接热循环对堆焊层成分、硬度和显微组织等有明显影响；使用176℃预热温度、145～190A电流参数和8～12cm／min焊接速度，可达97％以上堆焊合格率；在奥氏体不锈钢304H表面先用ER308L焊丝堆焊3mm厚隔离层，再采用400℃的预热温度和400℃的道间温度进行钴基合金堆焊，可以进一步降低堆焊层熔敷金属开裂的风险．
To study the hardfacing process of reactor vessel internals with cobalt alloys, the cobalt-base al- loy Stellite 6 was deposited on the surface of 304H stainless steel by gas tungsten arc welding （GTAW） process using different welding parameters, after which a series of tests were conducted on the deposited metal to analyze its chemical composition, cross-section microhardness, Rockwell hardness, intergranular corrosion and the microstructure, etc. Results show that both the electrical parameters and the weld ther- mal cycle have obvious effects on the chemical composition, hardness and microstructure of the deposited metal; under the welding parameters of preheat temperature at 176 ℃, welding current in 145-190 A and welding speed in 8-12 cm/min, the acceptance rate of deposited weld gets up to 97%; the risk of cracking of the deposited metal can be further prevented by depositing a 3 mm transition layer on the surface of stainless steel 304H with welding wire ER308L, prior to the final hardfacing process with cobalt-base alloy Stellite 6 at the preheat and interpass temperature of 400 ℃.
出处
《动力工程学报》
CAS
CSCD
北大核心
2016年第3期247-251,共5页
Journal of Chinese Society of Power Engineering
关键词
堆内构件
堆焊
钴基合金
显微组织
硬度
reactor vessel internal
hardfacing
cobalt-base alloy
microstructure
hardness
