A Kinetic Study on Ferromagnetic Phase Development in Mn - Al - C Magnetic alloy
소찬영Chan Young So, 이동희Dong Hi Lee
Abstract
A kinetic investigation was carried out on the development of ferromagnetic γ phase in Mn-Al-C alloys of three different carbon contents (O, 0.18 and 0.27 wt.% at a fixed Mn of 70 wt.%) by means of the isothermal heat-treatment at temperatures ranging 425∼600℃. The results obtained can be summarized as follows; 1) The transformation kinetics was interpreted as an autocatalystic reaction in which the induced stress developed during the growth of ε` phase from the high temperature εphase was believed to be responsible for the reaction. 2) The addition of carbon to Mn-Al binary alloy decreased the rate of transformation. The activation energy for the transformation from εto τphase was calculated to be 58.0, 59.1 and 60.1㎉/㏖ respectively for Mn-Al and Mn-Al-C specimens.