As a new polishing process, plasma polishing is a trend in stainless steel polishing. If we can make good use of plasma polishing will save us a lot of time and costs.
PVD and CVD are the most commonly used surface treatment methods for tools and moulds, CVD is based on chemical vapour deposition and PVD is based on physical vapour deposition, as they differ in principle, the final coating results are different and each has its own focus in application.
Electrolytic polishing has great advantages over traditional polishing, low cost, small footprint, can polish complex workpieces, has unmatched advantages over traditional polishing.
PVD stands for Physical Vapour Deposition. PVD coating refers to a thin film deposition technique whereby solid materials are sputtered or evaporated in a vacuum environment and deposited as pure materials or alloy components to form a coating on a substrate.
There are many different types of ion sources used in vacuum coating. The main ones are: high frequency ion sources, arc discharge ion sources, Kaufmann ion sources, radio frequency ion sources, Hall ion sources, cold cathode ion sources, electron cyclotron ion sources, anode layer ion sources, inductively coupled ion sources and probably many other types of ion sources that have not been mentioned.
Views: 33 Author: Site Editor Publish Time: 2022-07-13 Origin: Site
PVD is short for Physical Vapour Deposition, which means that under vacuum conditions, a low voltage, high current arc discharge technique is used to evaporate the target material and ionise both the evaporated material and the gas, using the acceleration effect of the electric field to deposit the evaporated material and its reaction products on the workpiece in vacuum coating. The physical process is used to transfer substances and form a metal or compound coating on the surface of the workpiece with special properties such as high strength, wear resistance, heat dissipation, corrosion resistance, oxidation resistance and insulation. The source of the coating is a solid material, which is evaporated or ionised by means of gas discharge or heating, and after "evaporation or sputtering", a solid material coating with different properties from the base material is produced on the surface of the workpiece under the action of an electric field.
During the PVD vacuum coating process, pressure fluctuations in the coater chamber can lead to uneven coating and poor repeatability. A mass flow controller controls the reaction gas and a pressure controller controls the pressure of the inert gas in the chamber to improve the final plasma vapour deposition (PVD) results.
Operating recommendation 1
The PVD vacuum coating process is usually carried out in a closed chamber under negative pressure. The reason for the vacuum is that ambient gases can interfere with the reaction process between the various substances involved in the coating, whereas under vacuum the vaporised metals, ionised molecules, plasma reaction compounds etc. can be fused with the plated surfaces of other materials.
Operating recommendation 2
A pressure controller solution is used to control the pressure of the inert gas charged into the vacuum chamber to create a well controlled coating environment. An external vacuum gauge directly connected to the reaction chamber measures the continuous process pressure and this pressure reading is transmitted via an analogue signal to the pressure controller and displayed.
The flow rate of the gases involved in the reaction into the chamber is controlled by a mass flow controller. Because the pressure controller as described above measures the pressure in the chamber and regulates the process pressure in real time by adjusting the content of non-reactive gases, the chamber creates a coating environment most conducive to deposition.
A fast control response is essential to minimise pressure fluctuations within the chamber and to create an optimum deposition environment. The PID values of the mass flow controller and pressure controller are customised to the varying process conditions of each application, effectively eliminating overfilling, reducing the time to set point and controlling the control response time to within 20-30 milliseconds, resulting in a stable pressure and gas exchange within the chamber.
Operation summary
1、Generally speaking, changes in the flow rate of the reaction gases during the vacuum coating process will disturb the pressure inside the reaction chamber and eventually lead to uneven and inconsistent coating.
2、The mass flow controller controls the various gases involved in the reaction chamber separately while the pressure controller controls the pressure in the chamber precisely within the specified range.
3. While the mass flow controller controls the various gases involved in the reaction in the chamber, the pressure controller precisely controls the pressure in the chamber within a specified range.
According to feedback from vacuum coating system integrators who have adopted the above solution, the excellent coating environment created by the precise and stable control of the very responsive flow controller and pressure controller has greatly improved the quality and repeatability of the coating results.