碳化氢

The crack initiates at stress concentration point in the root of weld, where has much more martenite, carbide and inclusion, and the serious hydrogen segregation.

裂纹均在焊缝根部应力集中处萌生，该处马氏体含量比较大，碳化物及夹杂物较多，氢的偏聚象严重。