Engineers working in manufacturing industries always prefer some additional surface treatments on the exterior of final products. Such treatments not only enhance the mechanical and electrical properties of the substrates but also give them a glossy finish. Hence, it helps in improving the overall functionality of the parts.
According to research, BlueWeave Consulting revealed that the global surface treatment market is suspected of boosting at a CAGR of 6.1% in the coming years.
In this article, you’ll learn about some popular surface treatment methods used on metal and non-metal parts. So, let’s dive into the post!
What is Surface Treatment?
Surface treatment is a technique that enhances the physical appearance and functional properties of an object’s surface. In addition, to improve the decorative properties, the primary aim of surface treatment is to offer corrosion resistance, longevity, and friction reduction to the object.
Moreover, surface treatments can be described as removal (scraping or melting) and additive processes( painting). Different heat treatments applied on the substrates are also classified as surface treatments. Some common examples of surface treatment include painting different colors on automotive parts and printing information about the company on products.
What are Different Surface Treatment Methods Used In Manufacturing Industries?
Several surface treatment methods for metal parts are used in manufacturing industries. Yet, the following are some frequently used surface treatments:
As the name implies, cleaning is the surface treatment process that removes oil, burrs, surface oxides, and other foreign substances. The lifespan of painting and planting can be increased if performed after surface cleaning. However, blasting and honing are two cleaning processes you can use to attain both cleaning and polishing.
Blasting is a process in which high-speed rotating wheels or water pumps are used to propel small particles at the substrate surface. It results in the removal of rust, dirt, corrosion, heat-treat scale, flash-burn, and paint. It also prepares the surface for other surface treatment methods.
Honing is a cutting technique used to improve the geometry and surface quality of the workpiece by using grinding wheels. It mainly deals with the interior surfaces of tubes or cylinder bores.
Electroplating is the most effective surface treatment method for metals in most industries. One or more thin metal layers are coated on the substrate surface during electroplating. The parts which are to be painted (cathode) are present in a salt solution containing dissolved metal ions (anode).
As the electric current is provided, the metallic ions of the electrolyte carry a positive charge which is attracted by the negatively charged metal part. In this way, the metal is deposited on the substrate part. Generally, chromium, copper, cadmium, silver, nickel, gold, tin, and zinc metals are used for electroplating.
3. Electroless Plating
Likewise electroplating, electroless plating also deals with the application of metal layers on the substrate surface. However, electroless plating doesn’t use an external electrical charge. The metal to be applied is present in the solution and adheres to the workpiece without any external assistance. This process allows you to experience a uniform deposit of metal, even on complex-shaped components.
Some common types of electroless plating include:
- Electroless nickel plating
- Electroless nickel with PTFE
- Electroless copper plating
4. Chemical Treatment
The chemical treatment method involves chemical reactions to create thin films of sulfide and oxide on the parts. Black oxide acts as a standard surface treatment for stainless steel components. Furthermore, the passivation removes the free iron from these stainless steel parts.
Usually, chemical treatment deals with corrosion protection, metal coloring, and surface priming.
5. Anodic Oxidation
Anodic oxidation is the best surface treatment technique for light metals, especially aluminum and titanium. By following the electrolysis, the oxide films are formed. Being porous, they allow specific coloring and dyeing agents to improve physical appearance.
Yet, the anodization of aluminum parts is a common method used to prevent corrosion. The process gives rise to a relatively thick, hard ceramic coating on the substrate to ensure durability.
6. Hot Dipping
The hot dipping process deals with the formation of a film of molten metal on a product surface. The substrate is dipped into a molten metal bath at a high temperature and then lifted out. Typically, zinc, aluminum, tin plating, lead, or solder is used to form metallic films.
However, hot dip galvanizing is the frequently used method for various steel products, such as metal meshes, tubes, wire ropes, guard rails, and many more.
7. Vacuum Plating
The vacuum plating method includes vacuum evaporation, sputtering, and ion plating. The fundamental role of all these steps is to achieve the effect of electroplating by forming metal and non-metal films on the surface. Typically, ionized metals, nitrides, and oxides are produced under optimum conditions. Then the substrate is put into the vacuum chamber, and metals are deposited.
8. Thermal Spraying
Thermal spraying is the surface treatment method in which materials are heated, collided, and then mechanically bonded to the substrate surface. Typically, a feedstock usually made of metal or ceramic is injected into a flame, plasma stream, or electrical arc to melt.
Primarily, thermal spraying is preferred for more oversized products in order to protect against high temperatures. It is ideal to attain electrical conductivity, high or low friction, chemical resistance, lubricity, wear, and other surface characteristics.
Painting is a well-known surface treatment method that many people use to enhance the look of parts. In addition, it serves to build the corrosion resistance property of the workpiece. A wide range of techniques is available to apply the paint on the surfaces, such as spray painting, brushing, dipping, electrostatic painting, and powder coat paint.
According to the latest industry trends, many automotive industries consistently use robotic arms to paint their vehicles.
Advantages of Surface Treatment
Surface treatment of metals is done for some purposes. Here are the crucial advantages of this process:
1. Offers Corrosion Resistance
The chemical degradation of metals and alloys because of a reaction with environmental agents results in corrosion. It is a massive threat to manufacturing industries as it leads to the contamination of products, loss of efficiency, and complete damage to the metallic equipment.
Luckily, surface treatments do wonders for corrosion resistance. The coating of specific noble metals on the workpiece minimizes the exposure of the surface to oxygen and humidity. Consequently, the process of corrosion slows down.
2. Extends the Lifespan
The lifespan of the substrate is associated with corrosion resistance. The more the product is corrosion-resistant, the more it is durable. This implies that by adopting surface treatment methods, you can ensure the longevity of your company products.
Moreover, if the machines you use for the production are surface coated, they’ll save your investments as there’ll be no need to buy new machinery more often.
3. Reduces Friction
Typically, friction is a retarding force that resists the relative motion of two objects. Therefore, friction is responsible for slowing down the moving parts of a machine. However, in some cases, it may result in sparks that can ignite fires in your company.
In order to prevent such severe circumstances, surface treatment is the best solution. By surface coating, you can smoothen the objects and reduce friction between them. Doing so allows you to work in a safe and secure environment.
4. Wear and Tear Resistance
Ensuring wear and tear resistance should be one of your highest preferences. The surface treatment methods reduce the wear and tear of your machine equipment during operations. Primarily, the reduction in friction between two parts allows these objects to experience more wear and tear without the fear of sparking.
5. Enhance the Appearance
Another advantage of surface treatment is that it improves the decorative properties of the products. As a result, the appearance of the surface becomes more pleasing and attractive. You can paint different colors of your choice during the surface treatment.
In a nutshell, surface treatment is a crucial asset for most manufacturing industries. In order to ensure the durability and better finishing of the products, you must adopt suitable surface treatment methods in your manufacturing processes.