Friction-induced temperature rise at energetic β-HMX crystal interfaces: Part II. Simulation of HMX rough surface under dry friction conditions

In this study, the frictional temperature rise of HMX/HMX is investigated with a rough surface sliding on a flat surface by finite element method. The simulation model on the frictional temperature on HMX surface is validated by the in-situ temperature monitoring at moderate friction conditions by tribological experiments and friction-induced ignition of HMX at extreme conditions by friction sensitivity tests. Simulation results reveal that the significance order of frictional parameter that determine the maximum temperature on the asperity of HMX is: friction coefficient > sliding speed > contact pressure. Surface roughness of HMX surface can also affect the frictional temperature rise. Furthermore, a frictional power density of ∼10.8 W/mm² is determined as the critical security boundary of the friction system when the critical temperature is set to 220 ℃. These findings can provide deep insights into the microscale hot-spot formation and frictional safety mechanisms of explosives.