材料科学
微晶
打滑(空气动力学)
裂缝闭合
疲劳试验
巴黎法
吕德斯乐队
应力集中
循环应力
断裂力学
强度因子
冶金
复合材料
微观结构
工程类
航空航天工程
作者
Avihai Petel,Aleš Jäger,Dotan Babai,Juergen Jopp,A. Bussiba,M. Perl,R. Shneck
出处
期刊:Metals
[MDPI AG]
日期:2023-04-17
卷期号:13 (4): 790-790
摘要
Short fatigue cracks in polycrystalline materials are very important from both practical and basic aspects, yet they are very difficult to observe. Therefore, it is suggested to emulate some properties of short cracks with long fatigue cracks in monocrystals. Indeed, such experiments in pure nickel crystals prove that the three peculiar properties of short fatigue cracks in polycrystalline metals are observed in long cracks in monocrystals, i.e., a lower threshold of the stress intensity factor (ΔKI)th, a higher crack propagation rate at low ΔKI regimes, and the fact that different cracks exhibit different growth behaviors. The fatigue experiments in monocrystals reveal interesting details of the slip activity at the front of fatigue cracks, including a selection rule for the active slip systems above and below the crack, the slip behavior under conditions of steep strain gradients, and the activation of a new slip system.
科研通智能强力驱动
Strongly Powered by AbleSci AI