Mechanical Milling Effect on Crystal Structures and Magnetic Properties of MnAs and Mn<SUB>0.8</SUB>Ti<SUB>0.2</SUB>As Compounds

DOI Web Site 15 References Open Access

Search this article

Description

The crystal structures and some magnetic properties have been investigated for MnAs and Mn0.8Ti0.2As compounds during mechanical milling. The lattice parameters and magnetization results measured for Mn0.8Ti0.2As compound, which has no structural phase transformation at Tc point, indicate that Ti substitution of some Mn can stabilize the B81 structure of MnAs compound, when subjected to mechanical milling. The changes of Tc in milling for Mn0.8Ti0.2As compound seem to result uniquely from the disordering effects, no relevent to the lattice volume changes as affect in the case of MnAs. Based on the thermodynamic model of Bean and Rodbell between Tc and lattice parameters, the milling caused disordering degrees in the two compounds were approximated by an atomic regularity parameter, which is shown to be monotonically decreasing with milling period. The minimum crystal size of the milled powder samples is about 20 nm and the pseudo-coalescence phenomena occur in the vicinity of 1.8×104 s similarly for both compounds. The transitions in the structural ordering and thermal stability during the whole milling process have been discussed according to a step mode for both compounds.

Journal

References(15)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top