Study of reaction mechanism of titanium powder with different particle sizes based on thermal analysis

The reaction kinetic characteristics of two different particle sizes of titanium powder under different heating rates are studied by the synchronous thermal analysis. The initial reaction temperature, exothermic peak temperature, and the temperature of maximum mass gain rate are analyzed by the thermal analysis curves with different particle sizes and heating rates. Results show that the ignition probability and combustion stability of titanium powder increase with decrease in titanium powder particle size. The activation energy and pre-exponential factor of titanium powder are calculated using the KAS method and the reliability of the calculation results is tested using the Ozawa method. The initial reaction temperature, the exothermic peak temperature, and the maximum mass gain rate temperature increase with the increase in the heat rate for 12.5 μm titanium powder. The average activation energy of 12.5 μm titanium powder is lower than the result of 51.3 μm titanium powder. The most probable mechanism function of titanium powder during the reaction process is obtained using the Coats–Redfern method.