Microstructure and mechanical behavior of polymer-derived in-situ ceramic reinforced lightweight aluminum matrix composite

Metal/alloy matrices have been previously reinforced with ceramic nanoparticles, but such reinforcements tend to agglomerate, weak interfaces, and are expensive. Polymer-derived ceramics (PDCs) based composites can potentially overcome these shortcomings. These obtained from the preceramic polymers after pyrolysis. inexpensive, be fragmented nanoscale, pyrolyzed in-situ. Friction stir processing (FSP) was used fragment disperse polymer within an Al-Mg alloy. The PDC particles pinned dislocations grain boundaries. composite exhibited a microstructure resulting dynamic recrystallization average size of ~1 µm. It also both high strength (96% 24% improvement in yield tensile strength, respectively) good ductility. Interestingly, serrations curves commonly observed alloys due Portevin-Le Chatelier (PLC) effect reduced composite.