Debye temperature of nanocrystalline Fe-Cr alloys obtained by mechanical alloying

TL;DR

This study investigates the Debye temperature of nanocrystalline Fe-Cr alloys produced by mechanical alloying, revealing phase-dependent variations and enhancements over bulk values using XRD, SEM, and Mössbauer spectroscopy.

Contribution

It provides the first detailed analysis of Debye temperature variations in nanocrystalline Fe-Cr alloys, highlighting phase-specific differences and the impact of nanostructuring.

Findings

Enhanced Debye temperatures in nanocrystalline alloys compared to bulk.

Detection of two distinct phases with different Debye temperatures.

Phase-dependent variations in Debye temperature within the alloy samples.

Abstract

A series on nanocrystalline Fe100-xCrx alloys prepared by mechanical alloying was investigated with X-ray diffraction (XRD), scanning electron microscopy (SEM) and M\"ossbauer spectroscopy (MS) techniques. XRD and SEM were used to structurally characterize the samples whereas MS permitted phase analysis as well as determination of the Debye temperature, Theta_D. Concerning the latter, an enhancement relative to bulk Theta_D-values was revealed in the range of ca. 40 < x <50. In a sample of Fe55.5Cr44.5 two phases were detected viz. (1) crystalline and magnetic with Theta_D=572(56) K and (2) amorphous and paramagnetic with Theta_D=405(26) K.