10F, Building B, Erqi Center, Erqi District,
Zhengzhou City, Henan Province, China
Coating is a process that paints layers of organic materials on the base metal. It makes the metal attractive and corrosion-resistant. There are four commonly-used coatings, including polyester (PE), silicone modified polyester (SMP), high durability polyester (HDP), and polyvinylidene fluoride (PVDF). Different coatings have different features and applications. Below are more details for your reference.
PE sheets are easy to process and have good adhesion. There are various colors to choose from. Besides, it’s the most cost-effective coating among other coating types. But its resistance to UV is poor. Therefore, the use of PE coating is limited. Its service life is 7-8 years.
2. Easy to process
4. Poor corrosion-resistance
Considering its good adhesion, PE is often used as a primer coat. While its resistance to corrosion is poor, it doesn’t suit the severe corrosive environment.
Polyester contains active groups -OH/-COOH, which can easily react with other polymers to improve the sunlight resistance and chalking properties of PE. Therefore, SMP has good color retention and heat resistance. Also, the corrosion resistance of SMP reaches 10-12 years. But its price is higher than that of PE. Because the adhesion and formability of silicone resin are not good, SMP color-coated steel sheets are not suitable for products that require multiple forming processes. Most of them are used for building roofs and exterior walls.
2. Heat resistant
It is often applied to roofing and exterior walls.
The outdoor weather resistance of HDP polyester coating is better than that of PE and SMP coatings, and its service life is up to 15 years. The high-durability polyester resin uses monomers containing cyclohexane structure during synthesis, which achieves a balance between the flexibility, weather resistance of the resin, and cost. At the same time, UV absorbers and hindered amines (HALS) are added to the paint formulation to improve the weather resistance of the film. Durable HDP coatings have been recognized by the market for high cost performance.
1. Higher UV resistance
HDP is widely used in the power and metallurgical industry, etc.
Due to the strong chemical bonding ability, PVDF coating has strong corrosiveness and color retention. Besides, its large molecular weight and linear structure offer great chemical resistance, and strong UV and heat resistance. Even in a typical environment, its service life can reach 20-25 years.
1. Excellent heat resistance
2. Great mechanical properties
3. Good resistance
It is often applied to chemical plants, power plants, and high-speed rail stations due to its excellent corrosion resistance and resistance to UV.
Below is a table to compare the performance.
|Coating Types||Hardness||Strength||Weather Resistance||Corrosion Resistance||Cost|
As mentioned, there are different types of paints on the market. You can choose a cost-effective one to suit your needs best.
You can also find a lot of paints brand, such as Nippon, Akzo Nobel, etc. You can select the one you like according to your budget.
Durability and heat resistance are influenced by the thickness of the coating. PVDF coating requires a thicker coating film, which makes steel products more durable. It has the best performance. If the environmental conditions are terrible, it is a suitable one for your project.
Color is the first concern for buildings. Your choice is mainly based on the surrounding environment and your preference. Besides, the light color paint has a stronger heat reflection. While dark colors are easy to fade when exposed to ultraviolet rays.
Painting is an affordable and effective method to protect the base metal from rusting and corrosion. It also makes the steel more smooth and more beautiful to meet the different requirements for different uses. Wanzhi Steel offers custom solutions, including paints, colors, designs, the thickness of coatings, etc. Welcome to contact us for details!