Thermal Properties of Amorphous TiPt Alloy Produced by Mechanical Alloying

Abstract:

The thermal properties of amorphous Ti-50at.%Pt alloy produced by mechanical alloying were studied by differential scanning calorimetry (DSC). The powders, sampled at various time periods during the milling process, displayed non-reversible exothermic reactions in the temperature range of 641-668 °C, and in the higher temperature range of 839-970 °C. The reaction peak temperatures and heat effects vary with milling time. The reactions at the lower temperature range were determined by X-ray diffraction analysis of the powder, heated beyond the onset temperature of the exothermic peaks, to be crystallisation into B19 TiPt. The reactions at higher temperatures are suspected twinning transformation of the B19 grains to form martensite. This requires confirmation by analysis with a transmission electron microscope, planned as part of future work.

• Periodical: Advanced Materials Research (Volume 1019)
• Pages: 372-378
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1019.372
• Online since: October 2014
• Authors: M.L. Mahlatji*, Silethelwe Chikosha, Hilda Kundai Chikwanda, Waldo Edmund Stumpf, Charles Witness Siyasiya
• Keywords: Amorphous Alloy, Crystallisation, Mechanical Alloying, TiPt

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