Review of metallic phase change materials for high heat flux transient thermal management applications

Metallic phase change materials offer an approach to rapidly transport heat away from a critical device, and to store that heat using the latent heat of fusion, buffering the temperature of a device during periods of transient high-power operation. Despite this interest, thermophysical properties and details of melting behavior of metallic alloys and compounds are scattered across the literature. Here, we critically review metallic phase change materials, and introduce quantitative comparative metrics to evaluate the relative performance of different compounds. This review focuses on (1) discussion of advanced prototype systems based on metallic phase change materials which rapidly absorb heat and buffer temperature rise in different devices and components, (2) historical development and focused applications of these materials by different communities, (3) identification of chemical alloy families with desirable melting characteristics, (4) critically evaluated thermophysical properties of different chemical alloy families, and (5) description of characteristic melting behavior in metallic systems. We focus here on describing different chemical classes of metallic phase change materials with melting points, T-fus, from near room temperature to < 1000 degrees C. The objective of this review is to assess the state of knowledge of metallic phase change materials, and to identify promising opportunities for further development. We conclude by identifying three critical areas for further development of metallic phase change materials.