Abstract

Higher manganese silicides (HMS), MnSi1.75–δ, were synthesized by mechanical alloying and consolidated by hot pressing. The optimum condition of mechanical alloying was ball milling at 400 rpm for 6 h, and sound sintered compacts could be obtained by hot pressing at temperature higher than 1073 K. The phase fraction of HMS showed no significant difference with compositional (δ) variation, but the MnSi1.75 specimen had the lowest fraction of MnSi of approximately 3%. The lattice constants of HMS with compositional variation were similar to values reported in the literature. All specimens showed Nowotny phase with tetragonal structure, and exhibited i-type conduction at measuring temperatures between 323 K and 823 K. HMS behaved as degenerate semiconductors in that the absolute values of the Seebeck coefficient increased and the electrical conductivity slightly decreased with increasing temperature. MnSi1.73 showed the highest figure of merit of 0.28 at 823 K.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.