Cu－Al粉末烧结合金内氧化研究

用高纯氮气体做介质对Ｃｕ－０．７５％Ａｌ粉末烧结合金进行内氧化处理，用Ｘ－ｒａｙ衍射，ＳＥＭ，ＴＥＭ等分析技术进行研究，结果表明：内氧化物由多相组成，晶内弥散分布的α－Ａｌ＿２Ｏ＿３质点呈球形析出长大；内氧化层中［Ａｌ］，［Ｏ］原子浓度规律分布，反应界面前沿存在［Ａｌ］，［Ｏ］原子浓度的非平衡区，内氧化过程，氧以晶界扩散和体扩散为主，氧化物质点周围Ｃｕ基体的塑性变形，增加了氧原子按位错扩散机制运动的几率；Ｃｕ原子受挤压发生短路迁移充填了邻近区域的空位和晶界缺陷，增加了粉末烧结合金的致密度．

InternL Oxiding of Cu-Al Powder Sintering Alloy

In this paper, internal oxiation treating is carried out with the samplees of 0.75% Al- Cupowder sintering alloy in internal oxiding apparatus using medium of high pure nitrogen gases.The samnles are studied by means of x-ray diffraction analysi.SEM and TEM, the resultsshow that the internal oxides are made up of many a phase. The oxide strips oxist in grainboundary and the spheerical x-Al_2O_3 partides are distributed within grain among internal oxida-tion layer. The composition distibution of [Al],[O] atoms possesses the regularity among thelayer and the non-equilibrium region of [Al],[O] atoms concentration exists in front of thereaction interface; The migration of [O] atoms is mainly conducted in the form of the grainboundary diffusion and the volume diffusion in the piocess of internal oxidation; The plasticdformation of Cu matrix around oxides partides incrdses the probability of [O] atoms movingin dislocation diffusion mechanism, The short-circuit migration of Cu atoms- xtruded due tovolume expanding of oxids precipitated fills up the hole and the grain boundary defect nearparticles. Which may increase the density 0f Cu-Al powder sinteering alloy.