Development of Ultra High Performance Thermal Management Technology for High Power Solid State Lasers for MDA Directed Energy Systems

High efficiency heat-sinks for thermal management of high energy solid state lasers are proposed. Advanced heat sink technology enables increased performance of directed energy solid state lasers. Efficient high performance thermal management materials representing next generation thermal expansion matched high thermal conductivity heat sinks are proposed with an additional level of hybridization: active coolant channels embedded during the manufacturing process. Three stages of heat sink hybridization are offered: 1) Particulate diamond reinforced Al engineered for CTE matching the laser-diode semiconductor (to minimize interfacial thermal impedance). By designing the internal interface between diamond particulates and the Al matrix alloy, isotropic thermal conductivity approaching ~600 W/mK (2.5 x OHFC Cu) is expected. Since the Diamond/Al composite is CTE matched to the solid state laser, a solder bonded low thermal impedance interface is enabled. 2) Diamond preforms will be hybridized with MMCC"s commercial milled graphite fiber MetGraf preform and co-infiltrated to form a low cost high efficiency heat sink/spreader. 3) For further hybridization, stainless steel or Kovar tubes will be embedded within the preform prior to pressure infiltration casting. When post-cast connected to a fluid or refrigerant cooling system, high capacity thermal transport from very small heat sinks is possible.