How to Select Steel Coils for Construction in the Middle East’s High-Temperature Environment

With the rapid development of infrastructure and the construction industry in the Middle East, the quality and performance of construction materials are increasingly being prioritized. As a critical material in building structures and decoration, the performance of steel coils directly impacts the safety and durability of buildings. The Middle East’s unique climate, characterized by extremely high summer temperatures, high air salinity, and intense ultraviolet radiation, poses stringent challenges for steel coil materials. Selecting appropriate steel coils suitable for the high-temperature environment of the Middle East has become a core challenge in ensuring project quality and durability.

1.Environmental Characteristics of High-Temperature Regions in the Middle East and Challenges for Steel Coils  

Extreme High Temperatures  

The Middle East experiences extremely high summer temperatures, with temperatures consistently above 40°C and occasionally exceeding 50°C during peak periods. High temperatures not only accelerate the aging of steel coil coatings but may also affect the mechanical properties of steel, such as reducing its strength and toughness, leading to structural deformation or fatigue.

High Salt Content in the Air  

Many regions in the Middle East are near the ocean, resulting in high salt content in the air. The salt fog environment accelerates the corrosion process of steel. Ordinary steel and coatings are prone to erosion in such environments, causing rust and peeling, which affects structural safety and appearance.

Ultraviolet radiation and dry climate

Prolonged exposure to strong ultraviolet radiation can cause organic coatings to decompose, age, and crack. Prolonged exposure can cause the coating to lose its adhesion, thereby accelerating the corrosion process of the steel. A dry climate may cause the coating to crack and peel off, reducing its corrosion-resistant effectiveness.

2.Key performance indicators for steel coil selection

Given the aforementioned environmental characteristics, steel coil selection should prioritize the following performance indicators:

Corrosion resistance performance

Coating thickness: The zinc layer thickness is the core factor for corrosion resistance in galvanized steel coils. For hot-dip galvanized steel coils, a zinc layer thickness of ≥275 g/m² is recommended to enhance resistance to salt fog corrosion.

Aluminum-zinc alloy coating: This coating offers excellent corrosion resistance and high-temperature performance, making it suitable for coastal salt fog environments.

Multi-layer organic coating protection: Color-coated steel coils typically use a multi-layer protection system consisting of primer, intermediate coat, and topcoat, providing excellent UV resistance and weatherability, thereby extending corrosion protection lifespan.

High-temperature resistance

Coating stability: In high-temperature environments, ordinary coatings may soften, bubble, or crack. PVDF coatings offer excellent UV and high-temperature resistance, making them the preferred choice for high-temperature buildings.

Steel substrate thermal stability: Select steel coils optimized through heat treatment processes to maintain high strength and good toughness, preventing performance degradation caused by high temperatures.

Mechanical Properties

Strength Grade: High-strength steel coils compliant with ASTM, EN, or GB standards are selected to meet structural load requirements.

Toughness and Ductility: Ensures formability and impact resistance during construction and use.

Thermal Expansion Coefficient

The thermal expansion coefficients of the steel and coating are matched to minimize coating cracks and steel deformation caused by extreme temperature differences.

3.Common Types of Steel Coils Used in Middle Eastern Construction

Hot-dip galvanized steel coils

Hot-dip galvanized steel coils form a zinc layer protective coating by immersing the steel coils in molten zinc, preventing oxidation of the base material. Their advantages include lower cost and reliable corrosion resistance, making them suitable for roof frameworks, structural steel, etc.

Application Recommendations: Select zinc layer thickness ≥275 g/m² to enhance corrosion resistance.

Disadvantages: The zinc layer is prone to oxidation in high-temperature and strong ultraviolet environments, so a protective coating is required.

Aluminum-zinc-coated steel coils

Aluminum-zinc-coated steel coils feature an aluminum-zinc alloy coating on the steel coil surface, offering excellent corrosion resistance and high-temperature performance. The aluminum layer blocks oxygen and moisture, while the zinc provides sacrificial protection.

Advantages: Superior high-temperature resistance compared to ordinary galvanized steel coils, particularly suitable for marine salt fog environments.

Application scenarios: Roofing, curtain walls, air conditioner housings, and other building components exposed to long-term environmental conditions.

Color-coated steel coils

Color-coated steel coils are produced by applying multiple layers of organic coatings to galvanized or aluminum-zinc-coated steel coils, combining corrosion resistance with aesthetic appeal.

Coating materials: PVDF coatings, known for their excellent high-temperature and UV resistance, are widely used in high-temperature environments such as the Middle East.

Functional advantages: Prevents UV damage and salt fog corrosion, maintains vibrant colors, and meets architectural aesthetic requirements.

4.Considerations for Selecting Steel Coils

Product Certification and Standards: Ensure that the steel coils comply with international or local quality standards to guarantee reliable material performance.

Supplier Qualifications and Services: Prioritize suppliers with extensive export experience and technical support capabilities.

Packaging and Transportation: High-temperature and salt fog environments impose stringent packaging requirements. Steel coils should be packaged using moisture-proof and salt fog-resistant specialized packaging to prevent damage during transportation and storage.

The harsh environmental conditions in the Middle East’s high-temperature regions impose stringent performance requirements on steel coils used in construction. By scientifically selecting steel coils with appropriately thick zinc coatings, excellent corrosion resistance, and high-temperature-resistant coatings, the safety and service life of building structures can be significantly enhanced. Combining galvanized steel coils with color-coated steel coils in residential roof applications not only meets corrosion resistance requirements but also ensures that the building’s exterior remains aesthetically pleasing and clean over the long term.