2025-04-09 09:00:00
Rocks often experience very rapid loading in both natural and engineering settings, such as during earthquakes, asteroid impacts, and mining activities. While advanced exper- iments can help us understand how rocks respond to these loading, they are expensive and time-consuming. Here, we developed a…
All spacecraft are increasingly at risk of hypervelocity impact from micrometeoroids and orbital debris. Meanwhile, new hypersonic weapons pose significant ballistic threats to military and civilian assets. In both scenarios, the declining effectiveness of traditional armor necessitates the creation of specialized, layered HVI protective…
When a shock wave reflects at the interface between the surface of a metal presenting geometrical defects and air, the defects invert and form thin jets. These jets expand ahead of the main metal surface, and the high strain rate they undergo leads to…
Architected materials over the last two decades have demonstrated unique combinations of properties previously unavailable in engineered materials. However, a variety of the envisioned applications for these materials such as, e.g., lightweight energy absorption, require a systematic understanding of mechanical responses across deformation rates….
Natural cellular materials exhibit both topological and material optimization. For instance, bone is a composite material of collagen (providing flexibility and toughness) and hydroxyapatite (a mineral that imparts stiffness and strength). The proportion and distribution of these materials vary according to mechanical demands. Inspired…
Soft granular assemblies are encountered in many natural systems and are important motifs in many engineered applications, from powder compaction to pharmaceuticals and biosystems. Understanding the mechanical behaviors of such granular systems is essential for their translational applications. It is understood that the mechanics…
Shock waves compress materials at a strain rate proportional to the peak pressure raised to some exponent, often ranging from 2-4. Phase transformations can be used to split shock waves into multiple, ramped shocks due to their sluggish kinetics relative to shock loading times…
Structural materials with engineered mesoscale architecture consisting of different constituents with contrasting mechanical properties are expected to offer superior combinations of strength and toughness. Whereas biological systems rely on a limited choice of organic and mineralized materials, modern additive manufacturing methods offer a wide…
Upon mechanical loading, the true stress-strain response of a polycrystalline metallic material traverses key stages, which include (i) an elastic-to-plastic transition, (ii) occurrence of peak stress, followed by (iii) gradual stress soft- ening, and (iv) degradation culminating into a complete loss of load carrying…
Soft materials, such as rubber and gels, exhibit rate-dependent response where the stiffness, strength and fracture patterns may depend on loading rates. Thus, accurate modeling of the mechanical behavior requires accounting for different sources of rate-dependence such as the intrinsic viscoelastic behavior of the…
