1.How does the coating material type affect service life?
Fluorocarbon coating (PVDF): A high-performance coating with a fluorine content of 70% or more. It boasts high molecular bond energy, strong UV resistance, and excellent acid and alkali resistance, with an outdoor lifespan of 20-30 years (e.g., building exteriors and high-altitude locations).
Silicon-modified polyester (SMP): Silicon-introduced to enhance weather resistance, resulting in a lifespan of 10-15 years. Suitable for moderate climates (e.g., inland urban factories).
Polyester (PE): A conventional civilian coating with moderate weather resistance and a lifespan of 5-10 years. Suitable for indoor environments or those with low UV and humidity (e.g., warehouse and workshop interior walls).
Other specialty coatings, such as polyvinyl chloride (PVC), offer excellent corrosion resistance but poor temperature resistance, with a lifespan of 8-12 years. Acrylic coatings offer weaker weather resistance, with a lifespan of 5-8 years.
2.How does coating thickness and uniformity affect service life?
Thickness: The topcoat thickness must be ≥20μm (normally 25-40μm), and the primer must be ≥5μm. Insufficient total coating thickness will result in insufficient "protection margin" and accelerated aging; excessive thickness (such as >60μm) may cause cracking due to stress.
Uniformity: Poor leveling of the coating, local coating leakage or pinholes will become a "breakthrough" for the invasion of corrosive media, significantly shortening the service life.
3.How do coating adhesion and flexibility affect service life?
When the adhesion (cross-cut test grade ≥1) is insufficient, the coating is prone to peeling due to temperature changes (thermal expansion and contraction) or external forces (such as vibration, impact), and loses its protective effect.
Coatings with poor flexibility (T-bend test ≤3T) are prone to cracking when the substrate is deformed, especially in low temperature or frequent temperature difference areas (such as winter in the north).
4.Do climate factors accelerate aging?
Ultraviolet radiation: The ultraviolet rays in high altitude (such as Tibet) and low latitude (such as Hainan) areas are strong, which will accelerate the breakage of the molecular chain of the coating, resulting in fading and powdering (such as PE coating in Hainan may powder to level 3 in 5 years).
Temperature and humidity: High temperature and high humidity (such as the rainy season in the south) will promote the hydrolysis of the coating and accelerate the growth of mold (polluting the surface); extreme temperature differences (such as -30℃ to 30℃ in the north) will cause the coating to expand and contract repeatedly, reducing adhesion.
Wind and sand and precipitation: Strong wind and sand (such as the northwest desert) will wear the surface of the coating (see the anti-wind and sand performance above); acid rain (pH <5.6) will corrode the coating (especially for PE coating, which may erode 2-3μm thickness each year).
5.How to prolong life?
Regular cleaning: Remove dust and oil from the surface every year (especially in industrial areas and coastal areas) to avoid reactions between pollutants and the coating.
Local repair: When damage to the coating (such as scratches or peeling) is found, seal it with special repair paint in time (matching the coating type, such as fluorocarbon repair paint for fluorocarbon coating).
Avoid mechanical damage: Prevent heavy objects from hitting and sharp objects from scratching to reduce human damage to the coating.