High-throughput diffusion multiples

A diffusion multiple is an assembly of three or more different metal blocks, in intimate interfacial contact, subjected to high temperature to allow thermal interdiffusion to create solid-solution compositions and intermetallic compounds. Using microscale probes, composition-structure-phase-property relationships can be established with an efficiency orders of magnitude higher than conventional one-composition-at-a-time practice. For structural materials, such relationships include phase diagrams, diffusion coefficients, precipitation kinetics, solution strengthening effects, and precipitation strengthening effects. Many microscale probes can also be used to study several materials phenomena. For instance, microscale thermal conductivity measurements can be used to study order-disordering transformation, site preference in intermetallic compounds, solid-solution effect on conductivity, and compositional point defect propensity. This article will use a few examples to illustrate the capabilities and developmental needs of this approach.