Diamond formed with strong chemical bonding has special mechanical and elastic properties. The hardness, density and thermal conductivity of diamond are the highest among known materials. Diamond also has the highest modulus of elasticity of any material. The coefficient of friction of a diamond film is only 0.05. In addition, diamond has the highest thermal conductivity, which increases by a factor of more than five if the diamond film is prepared using pure isotopes of carbon. The main reason for using isotopes of carbon to prepare diamond is to minimize the phonon scattering of diamond. As a superhard material, diamond film is a good coating material, which can be coated on the surface of cutting tools and molds to significantly improve their surface strength and increase their service life. The low coefficient of friction and high thermal conductivity of diamond films can be used for high-speed bearings for word aviation. The high thermal conductivity, low coefficient of friction and good light transmittance of diamond film also make it often used as the fairing material of missiles.
(2) Thermal Properties and Applications of Diamond
Nowadays, the thermal conductivity of synthetic diamond film is basically close to that of natural diamond. Because of its high thermal conductivity and high electrical resistivity, diamond can be used as the insulating layer of integrated circuit substrate, as well as the thermally conductive insulating layer of solid-state lasers. In addition, diamond’s high thermal conductivity, small heat capacity, especially at high temperatures when the heat dissipation effect is significant, is an excellent heat sink material. With the development of high thermal conductivity diamond thin film deposition technology, it has made the application of diamond thin film thermal deposition on high power lasers, microwave devices and integrated circuits a reality.
However, the properties of artificial diamond films vary greatly due to different preparation processes. For example, the thermal transport properties, which are mainly characterized by large differences in thermal diffusivity and thermal conductivity. In addition, the artificial diamond film shows strong anisotropy, and the thermal conductivity of the same film thickness parallel to the film surface is obviously smaller than that perpendicular to the film surface. These are caused by the different control parameters in the film forming process. It can be seen that the preparation process of diamond thin films needs to be further improved to make its excellent performance more widely used.
–This article is released by vacuum coating machine manufacturer Guangdong Zhenhua
Post time: May-24-2024