30CrMnSiNi2钢TIG焊接头电化学充氢后扩散氢逸出特征及示踪

高强度钢焊接接头不同区域组织对氢扩散与聚集的影响存在差异,采用显微镜摄影测氢法研究了电化学充氢条件下,30CrMnSiNi2钢TIG焊接头不同区域扩散氢的逸出规律,观察了氢气泡大小及分布特征;采用氢原子微印技术对焊缝区的扩散氢进行了示踪研究,探讨了高强度钢焊接头扩散氢逸出分布特征与低碳钢完全相反的原因,结果表明,30CrMnSiNi2A钢TIG焊接头扩散氢主要聚集在焊缝区及热影响区,焊缝区亚晶界为氢扩散和聚集的优先通道,组织中的内应力场是导致扩散氢聚集的根本原因. 研究结果对于研究焊接接头不同区域组织与扩散氢的关系提出了有益的思路.

Escape characteristic of diffusion hydrogen tracer in TIG welded 30CrMnSiNi2 steel with electrochemical hydrogen charging

The influence of different zones of high-strength steel welded joint on the hydrogen diffusion and aggregation is different. The escaping behavior of the diffusion hydrogen in different zones of TIG welded 30CrMnSiNi2 steel joint after electrochemical hydrogen charging is studied by microscopic photographing. The size and distribution of the hydrogen bubble were observed. The tracing of diffusion hydrogen in the weld zone is studied by using hydrogen microprint technique. The distribution characteristic of the escaped diffusion hydrogen in high-strength steel welded joint is explored, which is completely opposite to that in low-carbon steel. The results show that the diffusion hydrogen in TIG welded 30CrMnSiNi2 steel joint mainly gathers in the weld zone and the heat affected zone. The grain boundary in the weld zone is the main location to hydrogen diffusion and aggregation, the stress inside the structure is the primary cause of hydrogen diffusion aggregation. The results give constructive suggestions for understanding the relationship between different structure and the diffusion hydrogen.