制备Cu-TiB_2合金高能球磨及后续热处理过程的研究  

Study on preparation of Cu-TiB_2 alloy by mechanical alloying and in situ reaction

作　　者：申坤[1] 汪明朴[1] 郭明星 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083 [2]洛桑联邦理工学院力学冶金实验室

出　　处：《材料热处理学报》2010年第5期10-16,共7页Transactions of Materials and Heat Treatment

基　　金：国家高新技术发展"863"计划资助项目(2002AA302505);国家高新技术发展"863"计划资助项目(2006AA03Z517)

摘　　要：利用高能球磨以及高温热处理研究了原位合成高浓度Cu-2.5 wt%TiB2合金过程,并对其不同状态的组织、性能以及原位反应模型进行了研究。结果表明,随着球磨时间的延长,复合合金粉末显微硬度分三个阶段变化,即快速上升阶段,缓慢上升阶段和平稳波动阶段;组织经历相互焊合、形成交替分布的层状组织以及层状组织消失后的均匀分布组织;SEM和X射线衍射分析均表明长时间高能球磨不能在复合粉末基体内形成TiB2粒子;高能球磨60 h后的复合粉末其第二个DSC放热峰向低温区发生了明显的推移,初步判定激发其发生原位反应的最低温度为660℃。SEM观察发现复合粉末经后续900℃高温热处理后能够合成了大量细小的TiB2粒子,并绘制了原位合成TiB2粒子形成模型图。The mechanical alloying and high temperature heat treatment processes were employed to in situ synthesize 2.5 wt% TiB2 dispersion strengthened copper alloy by using Cu-Ti and Cu-B powders.In situ reaction model for the alloy was established,and microstructure and properties evolution in the process of preparing the Cu-2.5 wt% TiB2 alloy were investigated.The results show that with the increase of milling time,Vickers hardness of the powder increases rapidly and then gradually to a stable stage,and the homogenous microstructure composed of dispersive B particles in the Cu matrix with solid-solution Ti forms.No TiB2 phase is observed in the sample only by long time energy ball milling.Then lowest temperature for causing the occurrence of in situ reacting is about 660 ℃ in the milled powders.A large quantity of fine and uniform TiB2 particles is observed in the milled powder after heat treatment at 900 ℃ by SEM,and the in situ reaction models of forming TiB2 particles are given based on the experiments.

关 键 词：机械合金化 原位反应 Cu-TiB2合金 模型 

分 类 号：TG146.11[一般工业技术—材料科学与工程] TG166.2[金属学及工艺—金属材料]