【摘要】 恒塑性应变幅循环加载条件下,单滑移取向的Cu单晶体出现驻留带(Persistent Slip Bands,PSBs)。在铜的(0.3～0.5)TmK中温回复区内,对疲劳Cu单晶进行不同温度和时间的真空保温处理,观察PSBs结构在热激活条件下的变化及材料的寿命估计。结果显示,中温回复过程中,由于弹性力、渗透力与林位错阻碍力的交互作用促使PSBs中的位错通过空位的放出和湮灭而运动,并使PSBs的位错墙由弯曲到变细最后分段消失,位错密度快速下降。中温回复后材料寿命得到延长。更多还原

【Abstract】 In single-slip-oriented copper single crystals which were cyclically deformed under constant plastic shear strain amplitude control,Persistent Slip Bands(PSBs) was formed.Under intermediate temperature recovery of copper(0.3-0.5)TmK,by means of different temperature and different period of time,fatigued copper single crystals with PSBs were annealed in vacuum.The results show that during intermediate temperature recovery,the interaction of elastic force,penetrating force and tree dislocation resistance drive dislocations motion through annihilation and diffusion of vacancies and vacancy clusters,make some dislocations walls of PSBs bending and thinning,finally disappearing part by part under the mechanism of annihilation and have the density of dislocation falling rapidly.With the energy importing by an annealing treatment,the service life of "damage" components can be extended.更多还原