Hybrid Materials to Expand the Boundaries of Material‐Property Space

Abstract

The materials we use today for mechanical design are the outcome of at least 3000 years of development, much of it empirical but much the outcome of systematic science. Both approaches have been motivated by the desire for stiffer, stronger, more durable, and lighter structures, progressively populating material property “space”. We first examine the extent to which this space is now filled and estimate the ultimate constraints on this filling. Strategies for expanding the filled regions further include hybrid material design—making materials by combining two or more monolithic materials in chosen configurations and connectivity. Here we explore two classes of hybrid—lattice materials and sandwich structures—developing ways of comparing their properties with those of conventional monolithic materials. The comparison reveals the potential of hybrids. This paper builds on ideas that have grown from a long and rewarding collaboration with Tony Evans with whom it has been a privilege to have worked.

Mechanics of Multiscale Energy Dissipation in Topologically Interlocked Materials-11.1 STIR

“…Excellent agreement between model and simulation is obtained. (3) Provided understanding of the high rate loading (constant rate) of TIM assemblies. We have found that the principle underlying mechanism of the formation of force chains is again present, albeit somewhat mitigated if slip is considered.…”

“…Hybrid material systems are understood to provide efficient alternatives to conventional materials and fill holes in material property spaces [1][2][3]. One of the methods relevant for the creation of hybrid material systems is that of segmentation.…”

Multi-Objective Evolutionary Optimization of Sandwich Structures: An Evaluation by Elitist Non-dominated Sorting Evolution Strategy

“…The separation of the skins by the core increases the moment of inertia of the section and its section modulus producing a structure that resists bending and buckling loads well. Correspondingly, the core has to be stiff enough to ensure the skins do not slip over each other and make the sandwich structure behave as a load-bearing unit (Ashby, 2011). An adhesive layer also provided in a sandwich structure to assure the core and skins are bonded together.…”

“…The separation of the skins (faces), which actually carry the load, by a low density core, increases the moment of inertia of the panel with little increase in weight producing an efficient structure (Ashby, 2011). The studies on sandwich structures have been extensively continued due to the advantages in sandwich structures.…”

“…A chart of hybrid materials that combine two (or more) monolithic materials, or of one material and space. Reproduced by Ashby (2011) Fundamentally, ENSES is a sub-division of elitist multi-objective evolutionary algorithms. The ENSES is implemented with an effective sorting method based on individual ranking by non-dominated sorting and a crowded distance metric sorting, which evaluates the population density of solutions in the same rank as defined in NSGA-II.…”