You can often find thermal grease bridging the small gaps between an IC heat spreader and a heat sink. The trade-off for a design that utilizes a lower metal-concentration thermal grease is a lower thermal conductivity, such as 251G, which has a thermal conductivity of 0.765W/m.K. Depending on the polymer's electrical conductivity properties, a high metal-concentration thermal grease will also have higher electrical conductivity properties, which can increase the risk of electrically shorting the heat source or circuit. Thermal grease that contains high concentrations of metal compounds, such as WLPG-10, which boasts 10 W/m.K, will have significantly higher thermal conductivity than thermal grease with lower concentrations of metal. Based on the ratio, each grease mixture will have its own benefits and implications. The ratio between these two classes of ingredients dictates the grease's thermal and electrical conductivity properties. A polymer base commonly called a 'matrix'.The two main compounds that make up thermal grease―and most thermal connection devices―are: However, achieving these properties requires specific chemical compositions. Thermal grease's electrically-insulative, thermally-conductive nature allows manufacturers and builders to utilize it in almost all electronic applications that require connectivity between thermal management devices. Thermal Grease Properties: Thermal Paste Chemical Composition Without thermal grease, operating the heat source normally risks damaging the internal semiconductor die and integrated circuit. But it's not just about improving efficiency. Using thermal grease eliminates these air pockets, thus improving the subsequent thermal management accessories' effectiveness.

These air pockets would directly reduce the thermal management system's thermal conductivity. Without the use of thermal grease, a heat source in direct contact with a thermal accessory would develop an array of air pockets between the two devices. Thermal grease's liquid properties allow it to penetrate the microchasms in both the surface of the heat source and the surface of the thermal spreading accessory. W hat Does Thermal Grease Do?Īir, which happens to be a great thermal insulator, inhibits heat transfer from a heat source to the thermal management device. Thermal grease's goal is to reduce air pockets between the semiconductor chip's heat spreader and the thermally conductive material that moves thermal energy away from the heat source. Next, a heat sink, thermal spreader, heat pipe, or vapor chamber―or a custom configuration including all four devices―connects to the thermal grease. However, the casing protects the semiconductor material and integrated circuit from the thermal grease and other external factors. These casings, which are the first mode of transportation of thermal energy away from the semiconductor die, are thermally conductive. Thermal grease, which is designed to be electrically non-conductive, is applied directly to the casing (thermal spreader) of the CPU package. More specifically, the grease resides in the central processing units (CPUs), as these electronic components create large amounts of thermal energy that must be removed to perform properly. You'll often see thermal grease in use in computing devices.

Thermal paste