20CrMnTi钢旋挖钻机方头的失效分析  

Failure analysis of 20CrMnTi steel rotary drilling rig square head

作　　者：张俊花 周大鹏 郁永昊 康学勤[3] Zhang Junhua;Zhou Dapeng;Yu Yonghao;Kang Xueqin(Xuzhou Technician Branch,Jiangsu Union Technical Institute,Xuzhou Jiangsu 221151,China;Huaibei Blasting Technology Research Institute Limited Company,China Coal Technology Engineering Group,Huaibei Anhui 235000,China;School of Materials and Physics,China University of Mining and Technology,Xuzhou Jiangsu 221116,China)

机构地区：[1]江苏联合职业技术学院徐州技师分院,江苏徐州221151 [2]中煤科工集团淮北爆破技术研究院有限公司,安徽淮北235000 [3]中国矿业大学材料与物理学院,江苏徐州221116

出　　处：《金属热处理》2024年第8期301-304,共4页Heat Treatment of Metals

基　　金：中央高校基本科研业务费专项资金(2019XKQYMS17)。

摘　　要：旋挖钻机用20CrMnTi钢方头在使用30 d后发生断裂。通过断口形貌观察、化学成分分析、力学性能测试和显微组织观察,对20CrMnTi钢方头断裂原因进行了分析。结果表明:设计判据和材料热处理工艺选择不当,使方头材料强度、硬度低,使用过程中在扭转应力作用下在方头应力集中部位出现过载断裂。材料成分中P元素超标,材料有冷脆倾向,使断口呈现脆性断裂特征。加强原材料质量检验,使其成分满足标准要求。采用淬火+低温回火处理工艺,使方头材料强度和硬度满足技术要求。20CrMnTi steel rotary drilling rig square head was fractured after use for 30 days.Failure analysis was conducted through fracture morphology observation,chemical composition analysis,mechanical properties and microstructure analysis.The results show that both the design criterion and the heat treatment process are not so rational,which leads to decreased strength and hardness of the square head.Overload fracture is easy to occur at the stress concentration area of the square head under the action of torsional stress during the using.When the P element content exceeds the standard requirement,the material has a tendency towards cold brittleness,showing brittle fracture.The quality inspection of raw materials should be strengthened to meet the standard requirements.Quenching and low⁃temperature tempering should be adopted to ensure that the strength and hardness of the square head material meet the technical requirements.

关 键 词：旋挖钻机方头 20CRMNTI钢 失效分析 

分 类 号：TG162.7[金属学及工艺—热处理]