山东科学2025，Vol.38Issue(5)：57-64,8.DOI:10.3976/j.issn.1002-4026.20240124
超高压开关断路器三工位机构铜螺母断裂失效原因分析
Fracture analysis of copper nuts in the three-position mechanism of ultra-high voltage circuit breakers
摘要
Abstract
The three-position mechanism represents a critical mechanical component in ultra-high voltage switch circuit breakers,with the copper nut serving as a pivotal element.Premature failure of this component can significantly compromise the operational stability and longevity of the circuit breaker.This comprehensive investigation employs advanced analytical techniques to elucidate the underlying fracture mechanisms of the copper nut.Utilizing a multifaceted analytical approach,the study systematically examined the fracture morphology and material characteristics.Optical microscopy,scanning electron microscopy,and metallographic microscopy were employed to scrutinize the fracture surface and microstructural features.Complementary analyses using X-ray fluorescence spectrometry and electronic universal testing machine characterized the material's compositional and mechanical properties.The investigation revealed critical insights into the failure mechanism.Multiple crack initiation sites were identified within the fracture zone,characterized by coarse grain structures and an extensive network of precipitate particles localized at grain boundaries.The failure mode was definitively classified as cumulative fatigue damage.The primary crack source originated at the diameter transition of the shaft pin root'a structural stress concentration zone that represents the most vulnerable point in the copper nut's mechanical design.The findings underscore the importance of structural geometry and material microstructure in predicting and mitigating mechanical failure in critical electromechanical components.关键词
超高压开关/三工位机构/铜螺母/疲劳/断裂/应力集中Key words
ultra-high voltage circuit breaker/three-position mechanism/copper nut/fatigue/fracture/stress concentration分类
矿业与冶金引用本文复制引用
张树民,王小平,田静,许慧霞,刘珑,丁宁..超高压开关断路器三工位机构铜螺母断裂失效原因分析[J].山东科学,2025,38(5):57-64,8.基金项目
山东省科技型中小企业创新能力提升工程项目(2023TSGC0618) （2023TSGC0618）
