Effect of particle size and morphology on the sensitivity of ε-HNIW

Three kinds of ε-HNIW samples with different particle size and morphology were prepared by drowning-out recrystallization, and characterized by laser granularity measurement, polarization microscope and scanning electron microscope (SEM). The impact and friction sensitivity were tested and the thermal stability of HNIW samples were recorded by differential scanning calorimetry (DSC). Results indicated that the impact sensitivity of HNIW reduced rapidly with decreasing of particle size, thermal stability of HNIW reduced slowly. However, the friction sensitivity increased gradually along with the decreasing of particle size. HNIW with broad size distribution had higher mechanical sensitivity and thermal stability than samples with narrow size distribution. The HNIW with regular morphology had lower mechanical sensitivity and better thermal stability than samples with irregular crystals. The order of influencing factors on impact, friction and thermal decomposition of HNIW are particle size, size distribution and morphology.