Sintering is a material-bonding phenomenon that occurs under the application of heat. The porous structures formed by sintering powders are commonly employed as capillary wicks in two-phase heat transport devices such as heat pipes. These sintered wick microstructures are often not truly optimized for fluid and thermal performance. Understanding the role of sintering kinetics, and the resulting microstructural evolution, on wick transport properties is important for fabrication of structures with optimal performance. In this study, a cellular automaton model for predicting microstructural evolution during sintering is developed. The model, which determines mass transport during sintering based on curvature gradients in digital images, is first verified against benchmark cases, such as the evolution of a square into an area-preserving circle. The model is then employed to predict the sintering dynamics of a side-by-side two-particle configuration conventionally used for the study of sintering. Data from previously published studies on sintering of cylindrical wires is used for validation. Randomly packed multi-particle configurations are then considered in two and three dimensions. Sintering kinetics are described by the relative change in overall surface area of the compact compared to the initial random packing. The effect of sintering parameters, particle size, and porosity on fundamental transport properties, viz., effective thermal conductivity and permeability, is analyzed. The effective thermal conductivity increases monotonically as either the sintering time or temperature is increased. Permeability was observed to be largely independent of sintering conditions, but increases with particle size and porosity.

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