一种纳米晶合金中缺陷特征的正电子湮没寿命谱研究  

A Study of Characteristic of Defects in a Nanocrystalline Alloy by Positron Annihilation Lifetime

作　　者：王景成 尤富强 殷俊林 高国华 

出　　处：《上海钢研》2003年第2期3-7,共5页Journal of Shanghai Iron and Steel Research

摘　　要：用正电子湮没寿命谱仪测量和分析了Fe_(73.0)Cu_(1.0)Nb_(1.5)Mo_(2.0)Si_(13.5)B_(9.0)合金,该合金纳米晶化后有两类组织结构:一类是非晶结构,另一类是纳米晶结构;从缺陷形式上讲也有两种,一种是类空位,另一种是含有十来个单空位的空位团。类空位缺陷位于非晶区,空位团位于纳米晶区和晶粒的界面。Fe_(73.0)Cu_(1.0)Nb_(1.5)Mo_(2.0)Si_(13.5)B_(9.0)合金在非晶态时原子高密度区域与原子低密度稀释区域的分数之比约为1.44:1;纳米晶化后,经过480℃、500℃、540℃、580℃热处理,其类空位与空位团浓度的分数之比约为0.7:1。The measurements of the lifetime spectra of positron annihilation were performed for alloy Fe73.0Cu1.0Nb1.5Mo2.0Si13.5B9.0. Based on the data of the fitted lifetime spectra it may be suggested that the nanocrystallized Fe73.0Cu1.0Nb1.5Mo2.0Si13.5B9.0 consists of two microstructures: amorphous and nanocrystalline. Also, there are two kinds of microdefects: vacancy -like and vacancy cluster containing several monovacancies. The vacancy - like defects are located at the a-morphous zones and the vacancy clusters are located at the nanocrystallized zones and the intersections of several interfaces. In case of the as - quenched state of Fe73.0Cu1.0Nb1.5Mo2.0Si13.5B9.0, the ratio of the area fraction of high density of atoms to dilute area of atoms is about 1. 44 : 1. After nanocrystallization, the concentration ratio of the vacancy -like to vacancy cluster is about 0. 7: 1.

关 键 词：纳米晶合金 空位团 类空位 正电子湮没寿命谱仪 微观缺陷 

分 类 号：TB383[一般工业技术—材料科学与工程]