Deformation of Copper Single Crystals and Polycrystals at High Strain Rates

DOI Web Site Web Site 2 Citations

Bibliographic Information

Other Title
  • 高ひずみ速度における銅単結晶および多結晶の変形について
  • タカヒズミ ソクド ニ オケル ドウタンケッショウ オヨビ タケッショウ ノ ヘンケイ ニ ツイテ

Search this article

Abstract

The dynamic deformation behaviours of copper single crystals (99.999% purity) and polycrystals (99.99% purity) were investigated by compression tests at room temperature and partly at liquid nitrogen temperature, using a bar-bar type impulsive loading apparatus. Strain rates studied were of the order of 102∼103 sec−1 for the dynamic test and 10−4∼10−2 sec−1 for the static test.<BR>The time variation of the observed stresses at both ends of a specimen under dynamic test definitely shows the effect of plastic wave propagation. Crystals with orientations ranging from the middle to the [110]-[111] boundary in the stereographic triangle show higher critical resolved shear stresses and flow stresses and more extensive regions of stage I, followed by definite regions of stage II, under dynamic deformation than those under static deformation. The rates of work-hardening of stages I and II are shown to be independent of strain rate. The strain rate dependence in the stress-strain relations for crystals with orientations near [100] and polycrystals is negligibly small. Microscopic observations show that there is no remarkable difference in slip markings between the dynamically deformed specimen and the statically deformed one.<BR>It is concluded from the above results that for a high strain rate deformation of copper single crystals, the influence of the frictional stress on moving dislocations becomes too large to be negligible, if the dislocation density of the specimen is fairly small.

Journal

Citations (2)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top