Effect of strain rate and temperature on the mechanical behavior of magnesium nanocomposites

Magnesium-based composites with high specific properties have been found to be promising candidate for automotive and aerospace applications where materials are subjected to impact and elevated temperature conditions. AZ31B Mg alloy reinforced by 1.0 vol% silicon carbide nanoparticles was investigated under quasi-static and impact conditions. The impact tests were carried out on the split Hopkinson pressure bar in the temperature range from 243 K to 473 K. The temperature and strain rate effect on the compressive mechanical response of the material are discussed. The strain rate sensitivity, strain hardening behavior and temperature sensitivity of the material have been quantified. Comparative results of AZ31B and AZ31B reinforced with 0.5 vol% silicon carbide nanoparticles at room temperature (298 K) are also presented in terms of nanoparticle and its volume fraction effects. Quantitative conclusions are obtained of the strain rate effect on the mechanical behavior of these materials. All materials investigated have strong strain-rate dependence. The strength increases as the strain rate increases. The addition of nanoparticles was found to increase the material strength and energy absorption capability though an increase in ductility can be hardly observed.