The future development of coating industry must be vacuum coating

The future development of coating industry must be vacuum coating

Today there are two main types of professional coating methods,one is chemical deposition (CVD), one is physical climate accumulation, also called vacuum deposition (PVD).

Chemical coating is rich in a membrane element of gaseous reaction agent or liquid reaction required for other gas introducing echo chamber, in the process of chemical reaction to generate film substrate appearance attack. In the process of chemical film, simple solution pollution, if the coating appearance more impurities, owe better plating.
Chemical coating demand response temperature is very high, usually to control at 1000 ℃ or more, but many matrix data cannot be influenced by the high temperature, timely and cemented carbide, although can endured high temperature, because of the high temperature in chemical coating manufacturing environment will also constitute a coarse grains,which cause the brittle phase, function deterioration. If on the carbide TiN plating, diffusion of carbon will attack response and solution decarburized layer, the layer patience is poor, low flexural strength, constitute a taking shorten tool use.
Vacuum coating machine dispose of chemical coating attack in a series of questions excellently. Vacuum coating is under the condition of vacuum, choose low voltage, high current arc discharge skills, using gas discharge ability, use other discharge is the transpiration and restore the transpiration of target material and gas ionization, all using the accelerating effect of electric field, the accumulation and reaction products made by transpiration material on the workpiece.
All coating materials are in a vacuum environment after plasma accumulation in the appearance of workpiece, the disposal of the chemical plating solution of pollution question, not toxic or pollutants, plating film hardness higher, good wear resistance and corrosion resistance, more safe. Disposal of vacuum coating technology can control the temperature below 150 ℃ ~ 500 ℃, suitable for a variety of substrate materials, preparation of colorful coating, plating system of carbide cutting tools can make its full progress 2 ~ 10 times.

Electron Beam Evaporation Plating Technology

By electron beam eva​poration membrane after vaporization, condensation on the surface of the substrate is vacuum evaporation deposition techniques an important heating method. Many different types of such devices. With the extensive application of thin film technology, not only the requirements of film many species, but also on the quality of the film's more stringent requirements. Resistance evaporation deposition plating can not meet the needs of certain metallic and non-metallic. An electron beam source can be greater than the resistance of the heat source of the energy density, the value can be achieved (104- 109) W / CM2, so the membrane can be heated to 3000-6000 ℃. This is evaporated refractory metal and non-metallic materials such as tungsten, molybdenum, germanium, Si02, A1203 and so provide a better source. And because of the vapor deposition material is to be placed in the cold crucible, thus avoiding the reaction vessel and the evaporation material and the film material between the container material, which is to improve the purity of the film is very important. Additionally, heat can be directly applied to the membrane surface, thus high thermal efficiency, low thermal conductivity and heat radiation loss.

Electron beam (vacuum coating) is used as a heat source to melt membranes, its more categories, such as droplet, direct gun, ring and so on. Because these heat sources are a number of disadvantages for the vacuum evaporation apparatus, so in recent years has been replaced by magnetic deflection type electron beam source.

Vacuum coating machine film thickness measurement and monitoring methods

The most direct method for controlling coating vacuum coating machine is a quartz crystal balance method (QCM), this instrument can directly drive the evaporation source, through the PID control loop drive bezel to keep the rate of evaporation. As long as the instrument is connected with the system control software, it can control the entire coating process. But (QCM) accuracy is limited, partly due to its mass being monitored is coated rather than its optical thickness.

Also, while QCM very stable at lower temperatures, but at higher temperatures, it becomes very sensitive to temperature. In the long heating process, it is difficult to prevent falling into this sensitive area sensor, resulting in a significant error on the film. Dongguan Huicheng Vacuum Technology Co., Ltd. in vacuum coating equipment production has more than ten years experience in this introduction of modern vacuum coating machine film thickness measurement and monitoring methods.

Optical monitoring is the preferred way to monitor high-precision coating, it is because it can more precisely control the film thickness (if used properly). Improved accuracy due to many factors, but the most fundamental reason is that the optical thickness monitoring. OPTIMALSWA-I-05 single-wavelength optical monitoring system is the use of indirect measurement and control, combined with Dr. Wang developed advanced optical monitoring software to improve the optical response of the theories and methods of film thickness variation to reduce the sensitivity of the ultimate error, provide feedback or transmission selection mode and the wide range of monitoring wavelength. Particularly suitable for a variety of coating film thickness monitor comprises a non-structured film monitor.