Spall Failure of ECAE Mg-Al Alloys at Extreme Strain Rates: Influence of a Refined Precipitate and Grain Microstructure

The development of advanced materials for extreme dynamic environments requires an understanding the links between microstructure and response material (i.e., Materials-by-Design). Spall failure significantly limits performance at high strain rates, but our influence on spall strength is limited. While models suggest that increasing static yield by adding precipitates or refining grain size can improve strength, it possible associated increase in nucleation sites may have deleterious effects performance. Herein, we examine a Magnesium-Aluminum system with precipitation strengthening through novel high-throughput laser-driven micro-flyer (LDMF) impact experiments. Six microstructures are investigated, four sizes around 2–3 μm 0.5–1 μm, two precipitate-free 500 six nine percent Aluminum contents. LDMF method allows us to detect differences relatively small changes microstructure. observed be strongly affected varying levels consistently shows notable reduction average 8–19% addition precipitates, values ranging from 1.22–1.50 GPa. also seen decrease refinement independent composition. However, this compared hundred-fold reduction. ductile void growth across all samples, greater variability further numbers non-uniformly dispersed precipitates.