采用宏观检验、化学成分分析和金相检验等方法对供热管道开裂的原因进行了分析。结果表明:由于供热管道的热处理工艺选择不当,导致沿铁素体晶界析出大量成网状和链状分布的三次渗碳体,大大降低了供热管道的塑性和韧性,致使供热管道在使用过程中开裂。最后提出了改进措施。

The cracking cause of hot supply pipeline was analyzed by means of macroscopic examination, chemical composition analysis, metallographic examination and so on. The results showed that lots of tertiary cementite precipitatea long the ferrite grain boundary due to the improper heat treatment. The reticular and line distribution of tertiary cementite resulted in the great reduce of the plasticity and ductility of the hot supply pipeline, and finally led to cracking on the hot supply pipeline. At last the measures were presented.