Our Services
Physical Vapor Deposition (PVD) is an environmentally friendly vacuum coating process which results into formation of brilliant and durable decorative finishes on ABC (Architecture & Building Construction) Field, door hardware, household appliances, jewelry, stainless steel sheets, electronic components, automotive trim, and marine fittings.
By the dent of this method, a wide array of colors is coated on our products. Another advantage of PVD coating is that it gives a decorative finish coupled with wear and corrosion resistance.
PVD coating is one of the best methods for enhancing thin film plating elements. The vacuum deposition method coats the product with a film of hard refractory material 1-2 microns thick. PVD coating involves deposition of physical vapor of Titanium, Titanium Aluminium and Chromium. This process is also known as Titanium/ Titanium Aluminium/ Chromium plating.
The principle of Plasma Acceleration is used in the process of PVD coating. The method involves purely physical processes, such as low-temperature vacuum evaporation with plasma sputter bombardment.
There are three main types of PVD and all the three methods are undertaken in a chamber containing a controlled atmosphere at reduced pressure.
The three PVDs are:
- thermal evaporation
- sputtering
- ion plating
Thermal evaporation: In this method, the material is heated so that its vapor is used in condensing on a substrate to form the coating. Heating is done by various methods such as laser beam, hot filament, electrical resistance, electron, and electric arc.
Sputtering: This method involves the electrical generation of a plasma between the coating species and the substrate.
Ion plating: This involves the combination of thermal evaporation and sputtering.
These three methods can be used to directly deposit the material or for ‘reactive’ use in which chemical reaction occurs in the vapor phase between atoms of the coating material and ‘reactive’ gases.
The Process Of PVD Coating
The first step is to clean the stainless steel so that the coating will bond in a good fashion. The cleaned steel is then placed in a vacuum chamber where a target metal is situated which is used to create the coating. A high level of vacuum is maintained in the coating chamber and then a small amount of argon gas is passed through it.
In order to enable the stainless steel and target to bond well, a high voltage circuit is used. This will empower the argon ions to bombard the target and release the atoms of the target metal which will then be deposited on the stainless-steel substrate as a layer of coating.
This PVD process is known as sputtering and results in the deposition of plasma on stainless steel imparting its strength and luster.
Different metals such as gold (TiN), rose gold (ZrN), bronze (TiAlN), blue (TiAlN), black (TiAlCN), as well as a dark red (ZrN) can be used for coloring the surface coatings. This is basically the ceramic coating which is deposited as a very thin layer and thus makes the texture underneath visible. These PVD colors do not fade over time remain uniform in appearance. They are more abrasion-resistant than coloring which is done by the electrochemical processes.
Uses For PVD Coated Stainless Steel
There are is a broad spectrum of applications of PVD coated stainless steel products. The coatings prepared by PVD are put to multiple uses such as aluminum tracks and ceramic resistors for electronic circuitry; decorative coatings on plastics; corrosion resistant coatings on gas turbine blades; and wear prevention coatings for machine and press tools; anti-reflective ceramic coatings for optics.
A number of other important uses are:
# Architectural:
PVD colored stainless steel is widely used in various industries particularly, architectural and industrial designs. For e.g. railway stations, shopping centers, stainless steel curtain walls, and fit-outs of high-end retail stores, cladding and profiles for hotels and casinos, facades, etc.
# Transport:
PVD coated stainless steel is used in the transport industry as well such as paneling on the trains, ceiling, skirting on trains, wall cladding to shipping, etc.
# Ironmongery
The colored steel can be used for small products such as display cases, furniture, lighting fixtures, to door handles and taps.
# Jewellery
The PVD process is heavily used in stainless steel jewelry for the purpose of achieving some beautiful and radiant colors. PVD stable colors used in jewelry are gold, rose gold, coffee, black, dark grey, and blue. These colors are used for their polished, satin or matt finish depending on the product’s surface polish finish.
Benefits
Wear and weather resistant: The PVD process does not alter that original structure and texture of the stainless steel. It enhances the durability of the product and cuts down on its maintenance. A number of applications which involve exposure to wear and weather resistant activities have kept the material pristine in its original form. However, it is to be noted that the color can be damaged if it is attacked very aggressively and, in many cases, may not be repairable.
Appearance: You will get an amazing selection of unique colours on the smooth surface. Consequently, it dispenses with the need for further processing. It keeps the surface shinier than the original materials. A lustrous surface makes the material look plush and luxurious The product will not suffer from any distortion.
Cost-effective: PVD method is very economical method that works similar to traditional electroplating and effectuates in producing similar results. It dispenses with the need of using abrasive cleaners. You can easily wipe the surface of the material with a soft cloth.
Environmentally friendly process: The biggest advantage of the PVD process is that is completely environmentally friendly than other alternatives like electroplating and painting. There is no residue, no gases, no water waste produced. It is important to note that the colouring process does not put any constraints on the recycling value of stainless steel.
Scratch Hardness: The Kuremence Scratch Tester tested the Load of cracking point by scratching 150mm per minute. The result showed that Ion coating was 3 times harder than a chemical coating on scratch resistant hardness.
Resistance to corrosion and oxidation: PVD coating makes the surface resistant to corrosion and oxidation caused as a result of factors such as peeling, discoloration, tarnishing, cracking or peeling under normal conditions. The coating shields the product from scorching sunlight, salty water, and humidity.
Flexibility: The material coated with PVD imparts a low modulus of elasticity as a result of which it becomes extremely flexible. The PVD process lends a good thermal conductivity. This means there is no peeling or flaking of the coating at the time of bending.
Durability: Since the PDV Coating shields the surface of the product from corrosion, it makes the material durable. It works as an amazing long-lasting alternative for a gold finish. When compared with electroplating it is 15 – 25 times more wear-resistant.
Safety: The coating has been safety tested for surgical devices and food processing.
Thin film hardness: The hardness has been tested via the Vickers hardness test and was it was concluded to be 10 times harder than stainless steel.
Characteristics
What materials are suitable for PVD Coating?
A wide array of materials is applied with PVD Coating such as glass, stainless steel, and porcelain. When Stainless steel is exposed to environmental factors such as humidity and other factors, over a period of time, it gets oxidised and fades away. But when stainless steel has been PVD coated:
- It will not react with environmental factors and thus will not get tarnished, oxidized or discolored in the presence of sunlight saltwater or humidity.
- It will be available in a wide range of colors, surface patterns, and finishes.
- It will become impervious to UV light and there will be no flaking, cracking or discoloration of the material.