1.What are the differences in initial procurement costs?
Galvanized coil: Winner. As a commodity steel product, its base material cost and galvanizing process are very mature, resulting in low prices.
Aluminum alloy coil: Higher. The main reason is the high energy consumption and cost of bauxite refining and electrolytic aluminum production.
2.What is the difference between corrosion resistance and life cost?
Normal Atmospheric Environments (e.g., urban, rural):
Galvanized Coil: The zinc layer corrodes slowly; a zinc layer thickness of 80-275 g/m² can provide a lifespan of 10-30 years or more. High cost-effectiveness.
Aluminum Alloy Coil: A dense oxide film forms on the surface, resulting in an extremely slow corrosion rate and a lifespan of 50 years or more. High initial cost, but low annual cost per unit.
High Humidity, Coastal Chloride Ion Environments:
Galvanized Coil: The zinc layer reacts with chloride ions to form soluble zinc salts, accelerating consumption. "White rust" may appear, significantly shortening the lifespan.
Aluminum Alloy Coil (especially 3-series and 5-series): Much stronger resistance to chloride ion corrosion than galvanized steel. The preferred material for coastal areas, offering a significant lifespan advantage.
Industrial/Chemical Pollution Environments:
Galvanized Coil: Not resistant to acids and alkalis; corrosion accelerates in acid rain or alkaline environments.
Aluminum Alloy Coil: Better corrosion resistance, but attention must be paid to the corrosive effects of specific chemicals.
3.What are the differences between maintenance and replacement costs?
Galvanized coils: To extend their lifespan, or after corrosion occurs, they may require the application of anti-corrosion coatings, incurring material, labor, and downtime costs.
Aluminum alloy coils: Essentially a "one-time investment, lifetime maintenance-free" product, with maintenance costs approaching zero throughout their lifespan.
4.What are the differences in terminal residuals?
The recycling value of scrap galvanized steel is limited.
Scrap aluminum, on the other hand, is an "urban mine" with a high recycling value, typically reaching 70%-80% of the price of new aluminum ingots. Even after its designed lifespan, the aluminum alloy material itself remains a considerable asset.
5.What are the recommended materials for budget-sensitive, inland, general environments, and short-term use?
galvanized coil
The initial investment is minimal and can meet basic usage requirements.