1.How does coating material affect the ability to resist wind and sand wear?
The coating of color-coated coils usually consists of a primer (adhesion layer) and a topcoat (functional layer). The topcoat material is the key to wear resistance:
Polyester (PE): a conventional civilian-grade coating with medium wear resistance and a pencil hardness of about 2H-3H, suitable for areas with weak wind and sand (such as the eastern coastal areas).
Silicon-modified polyester (SMP): Silicon elements are introduced on the basis of PE, and the hardness is increased to 3H-4H. The wear resistance is better than PE and can adapt to medium wind and sand environments (such as inland cities).
Polyvinylidene fluoride (PVDF, fluorocarbon coating): an industrial-grade high-performance coating with a stable molecular structure, a pencil hardness of 4H-5H, and excellent impact resistance. It is the preferred choice for wind and sand wear resistance and is suitable for strong wind and sand areas (such as the northwest and around the desert).
Special enhanced coating: Some manufacturers will add ceramic particles and wear-resistant additives (such as aluminum oxide) to the topcoat to further improve the anti-friction ability, and the wear resistance can be increased by 30%-50%.
2.How do coating thickness and adhesion affect resistance to wind and sand wear?
Coating Thickness: Topcoat thickness is typically 20-50μm. Thicker coatings (e.g., 40μm and above) provide greater "wear margin," but adhesion must be maintained (as measured by a cross-cut test, with a grade of ≥1). Otherwise, the coating is susceptible to flaking due to wind and sand impact.
Primer Function: Primers (such as epoxy primers) enhance adhesion to the substrate, preventing overall coating detachment and indirectly ensuring durability and resistance to wear.
3.How do substrate properties affect resistance to wind-blown sand abrasion?
The corrosion resistance of the substrate (such as cold-rolled steel, hot-dip galvanized steel, and galvanized steel) will affect the performance of the coating after wear:
Galvanized/galvanized substrate: Even if the coating is partially worn, the zinc layer can form a sacrificial anode protection, delaying the corrosion of the substrate and extending the overall life;
Cold-rolled substrate: Without coating protection, the coating is prone to rust directly after wear, and is not suitable for high wind and sand environments.
4.What are the differences in wear resistance in different scenarios?
Low wind and sand areas (such as southern cities): PE or SMP coatings can meet surface integrity for more than 10 years, with only slight gloss decay and no obvious scratches.
Medium wind and sand areas (such as the North China Plain): SMP or thin fluorocarbon coatings (30-40μm) can last for 8-15 years, and minor scratches may appear locally, but it does not affect the overall protection.
High wind and sand areas (such as Xinjiang and the surrounding deserts of Inner Mongolia): Thick fluorocarbon coatings (≥40μm) or enhanced coatings are required, combined with aluminum-zinc-plated substrates, which can resist strong wind and sand impacts and have a service life of 15-20 years; if ordinary PE coatings are used, the coating may be damaged and the substrate may rust in 3-5 years.
5.What are the practical measures to improve resistance to wind and sand wear?
Prioritize high-performance coatings: Directly choose PVDF fluorocarbon coatings (thickness ≥ 40μm) or enhanced SMP coatings with wear-resistant additives.
Weather-resistant substrates: Use galvanized aluminum substrates (zinc content ≥ 150g/㎡) to improve the coating's corrosion resistance after wear.
Optimize installation techniques: Ensure the panel surface is flat during installation to reduce localized wear caused by wind and sand vortexes; seal corners and joints to prevent wind and sand from entering through gaps.
Regular maintenance: Clean the surface annually to prevent dust accumulation and the formation of "abrasives"; and apply specialized repair paint to areas of wear.