Among the many finishing options for aluminium extrusion products, powder coating is the most favoured, durable, and cost-effective alternative. Whether for products used in the home or in commercial businesses, powder coating increases protection from cold, heat, corrosion, scratching or even bleaching under the hot sun.
This technologically advanced finishing method is becoming popular in India. Whether it is used for aerospace products, exercise equipment, furniture tubes or vending machines, a decorative and environment-friendly finish is a valuable asset.
Process of Powder Coating Aluminium Extrusion Products
Powder coating finishes on aluminum extrusion products involve a systematic process, which starts with the pre-process inspection to check for any surface anomalies or damages. The rest of the process is covered primarily in three steps as follows:
- Pre-Treatment: The most important part of the process, this defines the durability and longevity of the end product. It involves the removal of dust, grease, or any other foreign particles using chemical and mechanical methods. This ensures that the surface is clean for enhanced adhesion and to prevent flaking.
- Powder Application: The powder used in the process is the fine mixture of coloured pigment and resin, which is commonly applied with an electrostatic spray gun. The powder is given a positive charge that causes it to bond to the electrically grounded surface of the product. Other powder coating methods are fluidized bed, electrostatic magnetic brush and electrostatic discs methods.
- Curing: The object is heated in an oven for a set duration at a fixed temperature, causing the powder to melt uniformly, thus forming a hard coating when cooled.
Powder coating finishes on aluminium extrusion products can be categorized into thermosets and thermoplastics. The polymers used most commonly are acrylics, polyester, epoxy, and the hybrid polyester-epoxy.
Advantages of Powder Coating Finishes
Powder coating finishes offer a number of benefits in addition to their cost effectiveness:
- The coating is fusion bonded and forms a thicker coating, providing better protection and longer product life.
- Since there are no solvents used, no volatile organic compounds (VOC) are released into the atmosphere, which makes the process more environmentally friendly than liquid finishing.
- Powder coating does not involve harmful carcinogens, unlike the liquid spray paint finish method.
- The wastes produced during the process can be recycled or disposed of in an environmentally friendly manner.
- Powder coating processes require significantly less energy for production.
Powder coating is an excellent alternative for creating a functional and beautiful finish for aluminium extrusion products.