摘要
以典型焊接结构部件为研究对象,构建基于载荷谱的寿命预测模型,采用Miner线性疲劳累积损伤理论评估焊缝区域的疲劳寿命。通过金相观察与断口扫描技术,系统分析失效部位的裂纹扩展机制与材料退化行为,识别出高应力集中区与焊接缺陷是影响使用寿命的主要因素。焊接部件在重复载荷和环境腐蚀作用下的疲劳寿命明显下降,部分关键焊缝在达到设计使用年限前已出现微裂纹萌生。为提高焊接结构可靠性,本文提出通过优化焊接工艺参数、引入结构缓冲设计及加强防腐保护等措施进行寿命延长。该研究可为农业机械焊接结构的可靠性评估与预防性维护提供理论依据与工程参考。
Taking typical welded structural components as the research object,a load spectrum-based life prediction model was established,and Miner’s linear fatigue cumulative damage theory was adopted to evaluate the fatigue life of weld zones.Through metallographic observation and fracture surface scanning technology,the crack propagation mechanism and material degradation behavior at the failure locations were systematically analyzed,and it was identified that high stress concentration areas and welding defects are the main factors affecting service life.The fatigue life of welded components decreases significantly under the combined action of cyclic loads and environmental corrosion,and microcrack initiation has occurred in some key welds before reaching the designed service life.To improve the reliability of welded structures,this study proposes measures such as optimizing welding process parameters,introducing structural buffer design,and enhancing anti-corrosion protection to extend the service life.This research can provide a theoretical basis and engineering reference for the reliability evaluation and preventive maintenance of welded structures of agricultural machinery.
作者
胡敏达
HU Minda(Jiangyin Secondary Vocational School of Jiangsu Province,Wuxi 214433,China)
出处
《农机使用与维修》
2025年第11期32-34,115,共4页
Agricultural Machinery Using & Maintenance
关键词
农业拖拉机
焊接结构
疲劳寿命
失效机制
裂纹扩展
agricultural tractor
welded structures
fatigue life
failure mechanism
crack extension
