孪晶铜中孪晶尺寸对疲劳位错组态的影响

对孪晶铜进行塑性应变幅控制下的疲劳实验，研究了不同宽度的孪晶内疲劳位错组态及演化过程．结果表明，孪晶宽度不同时，孪晶内的疲劳位错组态不同．当孪晶宽度大于1μm时，孪晶内疲劳位错组态与单晶中情况类似；孪晶宽度介于1μm到200nm之间时，位错形成类PSBs结构；孪晶宽度介于200nm到20nm之间时，孪晶内只能形成一些位错碎片；孪晶宽度小于20nm时，孪晶内没有稳定的晶格位错存在．

Effects Of Twin Size On The Dislocation Configuration During Cyclic Deformation Of Polycrystalline Twin Copper

Symmetrical push-pull fatigue tests were conducted on as--electrodeposited polycrystalline twin copper. Different dislocation configurations were formed in twins with different widths. When the twin width $W_{\rm t} >1~ \mu$m, loop patches and walls were found in twins, the same as that in single crystal; when 1um>W>200 nm, ladder--like structures formed in twin, which like persistent slip bands (PSBs); when 200 nm>W>20 nm, only some dislocation fragments were found; when W<20 nm, no stable crystal dislocation segments exist in the twin.