Abstract:

A preliminary study of microstructure and properties of the welded joint of low activation CLF-1 steel used for fusion reactor and 316L dissimilar metal by tungsten inert gas (TIG) welding using W19123L as filler material, has been performed. The welded joint forming is proved well and without defect. The welded joint consists of CLF-1 zone [base metal (BM), heat affected zone (HAZ), fusion zone (FZ)], inside layer (IL), weld zone (WZ), and 316L zone (BM, HAZ, FZ). Tensile strength of the joint is better than the base metal minimum value in room temperature. Both surfaces of welded joint are without crack and with deformation uniformity under the bending test. The distribution of impact value of the joint is concave-like and satisfies the designed values for the welded joint, the WZ’s value is the lowest, the HAZ’s of both WZ zones is the second, the BM’s was the best, and the 316L steel zone’s is slightly larger than the CLF-1 zone’s. The hardness values of the point under the 1.6mm top surface of welded joint have a larger fluctuation range, and is slightly higher than those of 1/2T and above down surface 1.6mm position. The hardness distribution of 1/2T and above the down surface 1.6mm position is roughly uniform, and has a downward trend from the CLF-1 zone to 316L zone. Welding properties generally has remained stable and satisfy the requirement of dissimilar steel welding performance matching.

Key words: Fusion reactor, Low activation, Dissimilar steel, CLF-1 steel, Tungsten inert gas welding

摘要：

对用W19123L 为焊丝的聚变堆用低活化CLF-1 钢与316L 钢的钨极氩弧焊(TIG)焊接接头金相组织及性能进行了初步研究。结果表明：焊接接头成型良好、无缺陷；金相组织表明焊接接头由CLF-1 侧(母材区、热影响区、熔合区)、过渡层、焊缝区、316L 侧(母材区、热影响区、熔合区)组成；室温拉伸试验结果优于母材的最低要求值；弯曲试验后的焊接接头内外表面完好，无裂纹产生，变形均匀；焊接接头冲击值成凹型分布，焊缝区冲击值最低，焊缝两侧热影响区冲击值次之，母材冲击值最高，316L 侧冲击值略高于CLF-1 侧，均满足焊接接头设计值；焊接接头上表面1.6mm 硬度波动较大，略高于1/2T 和下表面1.6mm 处，焊接接头1/2T 和下表面1.6mm 硬度分布较均匀，从CLF-1 侧到316L 侧有下降趋势。整体焊接性能基本稳定，满足异种钢焊接性能匹配要求。

关键词: 聚变堆, 低活化, 异种钢, CLF-1 钢, 钨极氩弧焊