纳米弥散第二相对变形弥散强化铜合金亚结构的影响

INFLUENCE OF NANO-SCALED DISPERSED SECOND PHASE ON SUBSTRUCTURE OF DEFORMATION DISPERSION STRENGTHENED COPPER ALLOY

利用TEM对Cu-Al2O3弥散强化铜合金的变形行为进行了研究。结果表明:纳米弥散第二相不仅可以提高基体中的位错密度,而且对位错的亚结构有重要的影响。细小的Al2O3弥散相的存在,导致合金变形时位错在基体中均匀、随机的分布,并使得位错胞组织难于形成,且数量较少。随着弥散程度的增加,变形中会产生更多的位错,位错胞形成更难,胞尺寸也进一步减小。

The deformation behavior of dispersion strengthened copper alloy Cu-Al2O3 was studied by TEM.The results show that nano-scaled dispersed second phase not only increases dislocation density in matrix,but also has an important influence on the dislocation substructure.The presence of fine dispersed Al2O3 particles results in an uniform and random dislocation distribution in copper matrix and makes the formation of dislocation cell structure difficult and decreases the amount of cell structure during deformation.Much more dislocations are occurred during deformation and dislocation cells are more difficult to form and the cell size is decreased with the increase of dispersion degree.