【作者】 任榕； 吴玉程； 汤文明； 汪峰涛； 郑治祥；

【Author】 REN Rong WU Yu-cheng TANG Wen-ming WANG Feng-tao ZHENG Zhi-xiang (School of Materials Science and Engineering,Hefei University of Technology,Hefei 230009,China)

【机构】 合肥工业大学材料科学与工程学院；

【摘要】 研究了 Fe₃₅Al₃₅Ti₁₀B₂₀（at%,下同）元素混合粉在机械合金化及等温退火过程中的结构演变及晶粒生长动力学,讨论了晶粒生长机制。结果表明,球磨过程中 Al、Ti、B 向 Fe 中扩散,形成 Fe（Al,Ti,B）固溶体。球磨70h 后,粉体主要由纳米晶 Fe（Al,Ti,B）构成。球磨70h 的粉体在热处理过程中 Fe（Al,Ti,B）分解形成纳米晶 B2-FeAl 及 TiB₂组成相。FeAl 晶粒生长激活能为1069．6kJ/mol,晶粒生长受到明显的控制,原位 TiB₂/FeAl 基纳米复合材料粉体的热稳定性高。更多还原

【Abstract】 Both the structural evolutions of Fe₃₅Al₃₅Ti₁₀B₂₀（at.%）elemental powder during mechanical alloying,and the structural evolutions and grain growth kinetics of the mechanically alloyed Fe₃₅Al₃₅Ti₁₀B₂₀powder during heat treating were investigated.The grain growth mechanism was also discussed.Results show that the diffusion of Al,Ti,B into the Fe lattice occurred during milling, leading to the formation of Fe（Al,Ti,B）supersaturated solid solution.After milling for 70h,the powder was composed of Fe（Al,Ti,B）. The decomposition reaction of Fe（Al,Ti,B）occurs to form FeA1 and TiB₂ during heat treating of the 70h milled powder.The grain sizes of both the B2-FeAl and TiB₂ are in nanometer scale.The activation energy for the nanocrystalline FeAl growth is calculated to be 1069.6kJ/mol.The grain growth of FeAl is significantly inhibited.The in-situ TiB₂/FeAl nanocomposite has a high thermal stability.更多还原