Abstract：To study the influence rule of particle size on minimum ignition temperature of magnesium-aluminum alloy powders, the Godbert-Greenwald furnace apparatus was used to measure the minimum ignition temperature of magnesium-aluminum alloy powders with different particle sizes, the experimental data were used to fit curves by choosing a variety of models. Six indexes such as coefficient of determination, standard error of estimate, total relative error, mean system error, mean prediction error, mean percent standard error were used to evaluate the models, so that the problem of no way to examin models due to less experimental data was solved and the best fitting model wsa obtained. The results show that the minimum ignition temperature increases with the increase of particle size. In the case of double parameters, the model Tmi=a0ea1d(a₀ and a₁ are parameters, d is particle size, T_mi is minimum ignition temperature) is the best fitting result. In the case of three parameters, the model Tmi=a0+a1d+a2lg d(a₂ is a parameter) is the best fitting result.

Keywords: magnesium -aluminum alloy powders; minimum ignition temperature; particle size；curve fitting