Application of vacuum in coating industry
Vacuum coating technology is an important branch of vacuum application technology. It has been widely used in the fields of optics, electronics, energy development, physical and chemical instruments, construction machinery, packaging, civil products, surface science, and scientific research. The methods used in vacuum coating mainly include evaporation plating, sputtering plating, ion plating, beam deposition plating and molecular beam epitaxy. There is also chemical vapor deposition.
If the purpose of vacuum coating is to change the physical and chemical properties of the material surface, this technology is an important part of the vacuum surface treatment technology. Now I will give a brief introduction to its main applications.
First of all, in terms of optics, a piece of optical glass or quartz surface is coated with one or several layers of thin films of different substances, which can become highly reflective or non-reflective (that is, antireflection coating) or as a reflective or transmissive material of any desired ratio. It can be made as a color filter that absorbs a certain wavelength and transmits another wavelength. High-reflection coatings start from large-aperture astronomical telescopes and various lasers to coatings for large windows in new buildings.
In terms of display devices, the transparent conductive films of video heads, high-density video tapes and flat display devices, light guide films of camera tubes, and aluminum linings of display tube phosphor screens are also prepared by vacuum coating. In terms of components, evaporating nickel and chromium in a vacuum, chromium or cermet can make resistors, evaporating aluminum, silicon monoxide, titanium dioxide, etc. on plastics can make capacitors, evaporating selenium can be used to obtain toner cartridges for electrostatic copiers, and evaporating barium titanate can be Manufacture of magnetostrictive sound elements, etc. Vacuum evaporation can also be used to make superconducting films and bead coatings for inertial confinement reactions.
In addition, it can also vapor-deposit decorative films on the surface of jewelry, clock and watch shells, textile metal patterns, gold and silver threads, and use sputtering or ion plating to make super-hard films on tools, molds, etc. The multi-arc ion plating that has emerged in the past two years to prepare titanium products, such as stainless steel sheets, mirror panels, cladding columns, handrails, high-end bed brackets, stair railings, etc., is currently prevailing.