ABSTRACT
The last few decades have experienced a surge in the advancement of science and technology for heterogeneous materials due to their increased industrial utilization. Examples of these materials are metal/alloy systems that contain multiple phases such as grains, precipitates and pores, and composite materials with a dispersion of fibers, whiskers or particulates in various matrix materials. These material systems have the promise of reducing weight and energy consumption, improving performance, thermo-mechanical stability and reliability, and also reducing life-cycle costs in engineering systems. In metallic systems such as cast aluminum alloys used in the automotive and aerospace industry, microstructural heterogeneities are often present in the form of silicon particulates, intermetallics, precipitates and voids. Depending on the processing route, differential cooling rates can produce strong morphological variations in spatial dispersion including localization and clustering or irregularities in phase shapes and sizes. Reinforced composites, on the other hand, are comprised of strategically designed microstructures for delivering desired physical and thermo-mechanical properties and even multi-functionality. Microstructures may, in some instances, have a high degree of non-uniformity or be graded. Stiff and strong second-phase inclusions of materials like silicon carbide, boron, or aluminum oxide are added to polymer, ceramic, or metallic matrices to enhance properties like stiffness, strength, creep resistance, and wear resistance of structures. Robust analytical and numerical modeling, accounting for microstructural details, is an indispensable ingredient of the material design process. These models are crucial in unraveling the underpinnings of microstructure-property relationships that govern the design process.
