作者: Tao Wang , Junshan Zhang
DOI: 10.1016/J.MATCHEMPHYS.2005.08.075
关键词: Analytical chemistry 、 Chemical reaction 、 Scanning electron microscope 、 Powder metallurgy 、 Materials science 、 Crystallography 、 Intermetallic 、 Activation energy 、 Diffusion 、 Exothermic reaction 、 Electron microprobe
摘要: Abstract The comprehensive kinetics of the exothermic TiAl3 synthesis reaction, under nominal formula Ti + 3Al → TiAl3, was studied by applying Friedman method to non-isothermal DSC data Ti–75 at.% Al powder compact. According characteristic dependence apparent activation energy (E) on conversion degree (α), three processes were identified with E 109, 175 and 89 kJ mol−1 in sequence. By correlating values reported ones, these could be interpreted as direct chemical reaction at interface between Ti(s) (l) form TiAl3, diffusion Ti through TiAl3-layer TiAl TiAl3-layer. In order verify thermokinetic interpretations metallographically, a laser-igniting self-quenching performed. laser-ignited self-quenched compact, there are regions reacted, transitional unreacted regions, respectively, along longitudinal direction. region, TiAl-layer remained core layer final product scanning electron microscopy (SEM) probe microscopic analysis (EPMA), which indicates is during process synthesis. Such metallographic result consistent interpretation.