Advanced Powder Technology, Vol.30, No.8, 1672-1677, 2019
On the mechanism of mechanochemical synthesis of Ti2SC from Ti/FeS2/C mixture
In this study, the synthesis of Ti2SC MAX phase by high energy ball milling, and the effects of heat treatment on ball milled powder was investigated. To this aim, a mixture of Ti, FeS2 (as sulfur source), and C according to Ti2SC stoichiometry, were ball milled by a planetary ball mill for different milling periods up to 10 h. The structural evolution, and the morphology of the products was studied by x-ray diffraction (XRD), and scanning electron microscopy (SEM) equipped with energy-dispersive spectroscopy (EDS), respectively. The results showed that after 10 h of ball milling, the raw materials reacted together and resulted in the formation of Ti2SiC and TiC phases. The ball milled powder was then compacted and heat treated at 1000 and 1200 degrees C. Heat treatment caused the progressing of synthesis reactions, and led to increasing the purity of Ti2SC phase. The heat-treated powder was leached in 1 M HCl for 2 h to remove iron from the product. The XRD results confirmed successful iron removal by leaching. SEM micrographs of the final product revealed the specific lamellar structure of MAX phases. Elemental mapping confirmed the homogeneous distribution of Ti, S and C elements. (C) 2019 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.