No 1, Vol. 4, 2001 

The effect of boron content on the crystallization behaviour and
microstructure for nanocrystalline Fe93-xZr7Bx alloys

X.Y. Xiong, T.R. Finlayson* and B.C. Muddle

School of Physics and Materials Engineering,
Monash University, P.O. Box 27, Clayton, Victoria,
Australia, 3168
*Correspondind author: Trevor R. Finlayson,


The crystallization behaviour of amorphous Fe93-xZr7Bx (x = 3, 6, 12 at.%) alloys and the microstructures of the primary crystallization products have been studied using a combination of differential scanning calorimetry, differential thermal analysis, x-ray diffraction and transmission electron microscopy. For x = 3 and 6 at.% the sole product of primary crystallization is the bcc (-Fe phase. The average grain size of the crystalline phase was 13 nm for the Fe90Zr7B alloy heated to 875 K at 20 K/min and 12 nm for the Fe87Zr7B6 alloy heated to 893 K at 20 K/min. However, when x = 12, primary crystallization results in a metastable phase with the cubic "Fe12Si2ZrB" structure and the α-Fe phase. The average grain size of this metastable phase was 35 nm for the alloy heated to 883 K at 20 K/min. Transformation of this metastable phase to predominantly bcc α-Fe can be induced by isothermal heat treatment at sufficiently high temperatures.

full paper (pdf, 66Kb)