疲劳Cu单晶驻留滑移带的演化及其内应力场  

EVOLUTION OF PERSISTENT SLIP BANDS AND ITS INTERNAL STRESS FIELD IN A FATIGUED COPPER SINGLE CRYSTAL

作　　者：杨继红[1] 李勇[1] 李守新[1] 马常祥[2] 王刚[3] 柯伟[1] 

机构地区：[1]中国科学院金属研究所材料疲劳与断裂国家重点实验室,沈阳110016 [2]东北大学材料物理系,沈阳110006 [3]沈阳大学信息工程学院,沈阳110044

出　　处：《金属学报》2001年第5期507-511,共5页Acta Metallurgica Sinica

基　　金：国家重大基础研究项目G20000671;G19990680;自然科学基金项目59971058资助

摘　　要：利用扫描电镜电子通道衬度（ＳＥＭ－ＥＣＣ）技术，对单滑移取向疲劳Ｃｕ单晶从基体脉络位错结构到驻留滑移带（ＰＳＢｓ）位错结构的演化进行了观察．且对这个演化过程中典型的位错结构进行了模拟计算，给出了ＰＳＢｓ演化过程中典型位错结构内应力场的分布．结果表明：在从基体脉络位错结构到ＰＳＢｓ位错结构的演化过程中，内应力的分布是不均匀的，位错密集区域（基体脉络和ＰＳＢｓ墙中）比位错贫乏区域（通道中）平均内应力分布相对集中，ＰＳＢｓ夹层与基体相比平均内应力的分布相对较弱，ＰＳＢｓ与基体边界处存在很大的应力差．由观察和计算结果对ＰＳＢｓ演化给出了一个新的可能的演化机制．The evolution from the so-call matrix vein to persistent slip bands (PSBs) in a fatigued copper single crystal of single-slip-oriented has been investigated by using electron channeling contrast (ECC) technique in a scanning electron microscope (SEM). The distribution of the internal stress field of typical dislocation structures in consecutive stages of PSBs formation was calculated by the method of discrete dislocation distribution. The results show that the distribution of internal stress is non-uniform in the evolution process from matrix vein to PSBs dislocation structures. In the dislocation dense regions (matrix vein and PSBs walls) the distribution of the internal stress is relatively more concentrated than that in the dislocation poor regions (channel). In a PSB the internal stress distribution is apparently weaker than that in matrix after the PSBs well formed. At the interface between PSBs and matrix, the stresses have a sharp transition. Finally a possible mechanism for PSBs formation was proposed.

关 键 词：疲劳Cu单晶 驻留滑移带的演化 内应力场 位错结构模拟 

分 类 号：TG614.121[金属学及工艺—金属切削加工及机床] TG113.255