(PCM): Naturally sticky materials, used in place of thermal pastes. Its application is similar to solid pads. After achieving a melting point of 55–60 degrees, it changes to a half-liquid status and fills all gaps between the heat source and the heat sink. Metal thermal interface materials (metal TIMs): Metallic materials offer substantially higher thermal conductivity as well as the lowest thermal interface resistance. This high conductivity translates to less sensitivity to bondline thicknesses and coplanarity issues than polymeric TIMs. See also Heat sink Heat spreader References Computer hardware cooling Heat exchangers Heat transfer Materials science