23MnNiMoCr54链条钢在使用过程中从焊缝接头处发生了断裂。对产生断裂的现象进行了详细分析,运用光谱仪、氧氮分析仪、扫描电镜和电子探针等仪器对试样进行了观察。研究结果表明,试样的化学成分、低倍分析、硬度分析均满足国标要求,断裂发生在焊缝处是由于外来Cu的进入引起晶界弱化,晶界强度急剧下降,从而导致焊接接头处发生断裂。为此,应对焊接工艺过程进行严格规范控制,提高焊缝处质量。 23MnNiMoCr54 chain steel during use from the weld joint rupture. The phenomenon of fracture was analyzed in detail. The samples were observed by using instruments such as spectrometer, oxygen and nitrogen analyzer, scanning electron microscope and electron probe. The results show that the chemical composition, low magnification analysis and hardness analysis of the sample all meet the requirements of the national standard. The fracture occurs at the weld due to the weakening of the grain boundary and the sharp decrease of the grain boundary strength due to the entrance of extraneous Cu, fracture. To this end, the welding process should be strictly regulated control, improve the quality of the weld.