【摘要】 基于金属磁记忆无损检测机理,铁磁性材料构件应力集中部位会发生具有磁致伸缩性质的磁畴组织定向和不可逆的重新取向。设计"原位"疲劳试验并且采用Bitter粉纹法对退火16MnR钢进行磁畴结构的观察,对比分析了不同疲劳周次对磁畴的影响。结果表明:整个研究区域以180°畴结构为主,同时具有树枝畴和少量的"回"型畴;随着疲劳周次的变化,所选特征晶粒内畴壁易发生约45°或90°翻转,导致畴结构在片状畴-树枝畴-"回"型畴之间变化。更多还原

【Abstract】 Based on the mechanism of non-destructive testing of metal magnetic memory,the magnetic domain structure of ferromagnetic stress concentration has magnetostrictive directional and irreversible reorientation.Designed "in situ" fatigue test and used Bitter powder pattern method for annealing 16MnR steel domain structure observation and compared the different effects of fatigue cycles to the magnetic domain.The results showed that the domain of whole research region was main 180 degrees domain structure,and branches domain and a small amount of "tetragonum" type domain.As the fatigue cycle changes,the domain wall of selected grain was easy to occur about 45 degrees or 90 degrees rotation,leading to the domain structure changed among lamellar domain-branch domain-"tetragonum" domain types.更多还原