低碳钢与不锈钢焊接接头弯曲性能的分析

Analysis of bending property of dissimilar steels welded joints

关键词:  焊接接头  异种钢  脆性过渡层  弯曲性能

Key words:  welded point  dissimilar steel  brittle transition layer  bending property

摘要:

通过对Q235-B和316L异种钢I形和Y形坡口埋弧焊对接接头Q235-B一侧熔合区显微组织和元素分布及显微硬度的观测和分析,指出了在碳素结构钢与不锈钢异种金属的焊接接头中,碳素结构钢一侧出现硬而脆的熔合区;提出了减小熔合区的宽度是提高异种钢焊接接头抗弯曲性能的关键.此外研究了不同焊接工艺对焊接接头抗弯曲性能的影响机制,采用小尺寸的Y形坡口和使用含镍量高的焊丝,既有效地减小了熔合区的宽度,提高了异种钢焊接接头的抗弯曲性能,避免在对接接头双面埋弧焊时发生烧穿焊接缺陷.

Abstract:

The dissimilar steel welded joints were made between Q235-B carbon steel and 316L stainless steel by submerge arc welding using Y and I patterns of welding groove. Based on the observation and analysis of the microstructure,elements distribution and micro hardness in the weld fusion zone near the Q235-B base metal,the hard and brittle transition layer would form in the fusion area near the carbon structural steel, when the dissimilar steels were welded. The decrease of width of brittle transition layer is the most important to improve the bending property of the dissimilar steels welded joint. Furthermore, the influences of different welding procedures on the bending property of the welded joint were investigated. The process of Y pattern groove and Ni-riched welding wire can minimize the width of brittle transition layer and raise the bending property of the welded joint. Besides,this welding procedure also avoids the welding fault of burning through when the butt joint of the dissimilar thin steel was welded by submerged arc welding on the double sides.