机械合金化制备Cu-C纳米晶复合粉末

Nanocrystalline Copper-carbon Composite Powders Prepared by Mechanical Alloying

研究了不同碳含量的铜-碳混合粉末在机械合金化(MA)过程中组织形态特征及微观结构的变化规律。结果表明:粉末X射线衍射图谱的宽度和强度均随着球磨时间的延长逐渐加宽和降低,这是晶粒细化和晶格畸变共同作用的结果。随着机械合金化的进行,粉末的晶粒度逐渐减小,而晶格常数和畸变则不断增加。不同碳含量的铜-碳混合粉末经过24 h高能球磨后均可形成纳米级的铜基过饱和固溶体。机械合金化导致复合粉末晶粒的细化、晶界、亚晶界以及位错等晶体缺陷密度的增加是形成过饱和固溶体的主要原因。

The characteristics of morphologies and changes of the microstructures in mechanicalal alloyed for different carbon content mixed powders were investigated. The results showed that the width of X-ray diffraction lines width increased and strength decreased with ball milling thne, it was caused by the reduction of crystal size and the increase of microstrain. With the prolongation of milling time, the crystal size of mixed powder reduced, while the lattice constant and lattice distortion increased gradually. After milling for 24 h, nanocrystalline supersaturated Cu-based solid solutions were formed for different carbon content mixed powders. The formed defects such as grain boundary, sub-grain boundary and dislocation were the important reason for developing supersaturated solid solution.