摘要
研究了脉冲电流对20低碳钢疲劳损伤的修复及其机理。对预疲劳原始疲劳寿命的60%周次的试样进行脉冲电流处理,修复其疲劳损伤,再继续进行疲劳试验,发现试样总的疲劳寿命比原始试样疲劳寿命延长了41%。对比分析了脉冲电流处理对试样的微观组织形貌和力学性能的影响,发现20钢在脉冲电流作用下未发生强化,表明疲劳寿命的延长是由于脉冲电流的修复作用造成的。TEM观察发现,经过脉冲电流处理后,疲劳试样铁素体中观察到的墙状位错结构部分消失,位错分布更为均匀。此外,脉冲电流处理可以有效地修复疲劳损伤材料的微观缺陷,延长材料的服役寿命。
The fatigue damage recovery of 20 low carbon steel by pulse current as well as the mechanism were investigated.A pulse current was applied on the pre-fatigued specimens with 60%of the original fatigue life cycles to recover the fatigue damage,and the total fatigue life of the pulse current treated specimens is increased by 41%compared with the original ones.The effects of pulse current treatment on the microstructure and mechanical properties of the specimens were analyzed.The results reveal that absence of strengthing is observed in 20 low carbon steel under the action of pulse current,indicating that the prolongation of fatigue life is attributed to the recovery effect of pulse current.TEM observation reveals that after the pulse current treatment,the wall-like dislocation structure observed in ferrite of the fatigue specimens is partially disappeared,and the dislocation is more evenly distributed.Moreover,pulse current treatment may be an effective way to recover the micro-defects of fatigue-damaged materials,extending the service life of the materials.
作者
刁爱民
王景鹏
杨雨秋
刘纪德
郭敬东
Diao Aimin;Wang Jingpeng;Yang Yuqiu;Liu Jide;Guo Jingdong(College of Naval Architecture and Ocean Engineering,Naval University of Engineering;Shenyang National Laboratory for Materials Science;Institute of Metal Research,Chinese Academy of Sciences;School of Materials Science and Engineering*Shenyang Ligong University)
出处
《特种铸造及有色合金》
CAS
北大核心
2022年第3期318-322,共5页
Special Casting & Nonferrous Alloys
基金
国家重点研发计划资助项目(2020YFA0714900)。
关键词
脉冲电流
疲劳寿命
损伤修复
钢
Pulse Current
Fatigue Life
Damage Recovery
Steel
