Microstructure and Mechanical Behavior of Pumice Particle Reinforced Magnesium Matrix Composites

In the present study, novel, lightweight and low-cost Mg/pumice composite materials have been developed for the first time. Mg matrix composites reinforced with 3–12 vol.% pumice powders were produced by hot pressing at 600 °C for 1 h under 50 MPa pressure. Microstructural analysis revealed that in-situ Mg₂Si and MgO phases formed as a result of chemical reaction between pure Mg powders and SiO₂ present in the pumice powders during processing. The room and elevated temperature (150 °C and 200 °C) yield and compressive strength of the composites increased with increasing reinforcement content. The increments up to 47.5% in yield strength and 53% in compressive strength at room temperature have been observed. Similarly, the utmost increments in yield and compressive strength at elevated temperatures were 72% and 50.5%, respectively. Ductility (especially at the room temperature) of the composites on the other hand was almost independent of the reinforcement content.