复合板封头开裂失效原因分析

Cracking failure analysis of composite board head

通过宏观分析、微观组织分析和扫描电镜分析等方法分析了DN6200复合板封头开裂的原因。结果表明,不锈钢板双面焊中心连续分布的线型缺陷是DN6200复合板封头加工时开裂的一个重要源头;碳钢基材内部大量的空洞是过载断裂时大韧窝的来源,是造成材料组织不均匀的重要原因之一。

In order to found the cracking reason of the DN6200 head of composite board, the macro-analysis,microstructure analy- sis,SEM analysis were adopted. Results show that： the continuous linear defects in the double sided welding axis of stainless steel clad is an important source of cracking;a lot of cavity in the base material of carbon steel can causes many dimples under the condition of overload fracture, it is one of the important reason which causes material performance nonuniform.