【摘要】 推移框架上的推杆尾由27CrNiMo锻件加工而成，工艺路线：锻造→气割→机加工→热处理→拼焊，该锻件在矿上使用过程中出现断裂现象。采用宏观观察、化学成分分析、金相检验、力学性能测试、扫描电镜分析等方法对工件断裂原因进行综合分析。结果表明：断裂的推杆尾为脆性断裂，断面可见放射状扩展图案，断口形貌特征为沿晶+穿晶断裂，为典型的脆性断口。在腐蚀环境中，裂纹起源于角部焊缝内部焊接缺陷处的过渡圆弧部位，该处存在孔洞和夹渣缺陷，这些因素造成母材锻件沿水平纵向扩展引发锻件断裂。更多还原

【Abstract】 The push rod tail on the pushing frame is made of 27CrNiMo forging, and the process route is: forging →gas cutting →machining →heat treatment →welding. The forging broke during use in the mine. A comprehensive analysis of the cause of workpiece fracture was conducted using macroscopic observation, chemical composition analysis, metallographic examination, mechanical property testing,scanning electron microscopy analysis, and other methods. The results indicate that the fractured tail of the push rod is brittle fracture, with radial expansion patterns visible on the fracture surface. The fracture morphology is characterized by intergranular and transgranular fracture, which is a typical brittle fracture. In a corrosive environment, cracks originate from the transition arc at the internal welding defect of the corner weld, where there are holes and slag inclusion defects. These factors cause the base metal forging to expand propagate horizontally and longitudinally, leading to the fracture of the forging.更多还原