FeBSi非晶合金常规和电脉冲加热退火脆化及其微观结构的研究

A Study on Annealing Embrittlement and Microstructure ofFeBSi Amorphous Alloy by Conventional andHigh Density Electropulsing Methods

对非晶Ｆｅ７８Ｂ１３Ｓｉ９合金进行了低温等时及电脉冲加热退火处理。用高分辨率电子显微系统观察分析合金脆化前后的微观结构变化。试验结果表明，常规退火时合金的低温脆化是其淬态存在的类Ｆｅ３Ｂ原子排列短程有序区长大至３～７ｎｍ所致；电脉冲加热由于能抑制类Ｆｅ３Ｂ有序区的发展并使其“碎化”而避免脆化的发生。电脉冲加热后合金的脆化与ｂｃｃα－Ｆｅ晶粒的形核有关。

Methods of high current density electropulsing and conventional isochronal were used to anneal Fe78B13Si9 amorphous alloy. The alloy microstructures before and after embrittlement were investigated systematically by means of high resolution electron microscopy. The results show that the conventional annealing embrittlement is caused by that Fe3Blike atomic short range order in asquenched state has grown to about 3～7 nm. Embrittlement can be avoided by high current density electropulsing because growth of the Fe3Blike atomic short range order is restrained and broken. The embrittlement by high current density electropulsing is related to the nucleation of bcc αFe.