When sourcing coated steel for roofing, siding, or industrial fabrication, one of the most critical decisions is choosing between galvalume steel coil AZ50 vs AZ150. These two coating grades—defined by their aluminum‑zinc alloy mass per square meter—directly impact corrosion resistance, formability, and project lifespan. As a leading galvalume supplier China, ChinaCNU Steel produces both AZ50 and AZ150 from our ISO‑certified Qingdao factory, backed by 15+ years export experience to over 50 countries. This guide breaks down every difference so you can select the right aluzinc steel coil for your budget and performance needs.
Understanding Galvalume Coating: AZ50 and AZ150 Defined
Galvalume, also known as aluzinc steel coil, is a 55% aluminum‑zinc alloy coating applied to cold‑rolled steel. The “AZ” designation refers to the coating mass: AZ50 means 50 g/m² total coating (both sides), while AZ150 means 150 g/m². This coating is the primary defense against corrosion, especially in metal roofing coil applications where exposure to rain, salt, and UV is constant. At ChinaCNU Steel, our galvalume steel coil AZ50 vs AZ150 products meet ASTM A792 and are available with FOB pricing from our Tianjin Xingang port.
Galvalume Steel Coil Az50 Vs Az150 Price Trend (USD/Ton) – Last 12 Months
Data: ChinaCNU Steel Market Research | FOB Tianjin Reference Price
How Coating Mass Affects Performance
The AZ150 galvalume grade offers three times the coating weight of AZ50. This directly translates to superior barrier protection: the thicker alloy layer prevents oxygen and moisture from reaching the steel substrate. For galvalume steel coil AZ50 vs AZ150 decisions, environments with high humidity, industrial pollution, or coastal salt spray demand the heavier coating. Conversely, AZ50 works well in dry, interior, or sheltered applications where cost efficiency is prioritized.
Key Differences: Corrosion Resistance, Formability, and Lifespan
When comparing galvalume steel coil AZ50 vs AZ150, three factors dominate: corrosion resistance, formability during fabrication, and expected service life. Below is a data‑driven comparison based on ASTM standards and real‑world field data from ChinaCNU Steel’s export projects.
| Property | AZ50 (50 g/m²) | AZ150 (150 g/m²) |
|---|---|---|
| Total coating mass (both sides) | 50 g/m² | 150 g/m² |
| Coating thickness per side | ~7 µm | ~21 µm |
| Salt spray resistance (ASTM B117) | ~500 hours | ~1,500 hours |
| Typical service life (rural/industrial) | 8–12 years | 20–25 years |
| Formability (bending, roll‑forming) | Excellent (thin coating) | Good (thicker coating) |
| Common applications | Interior panels, ducts, light roofing | Exterior roofing, coastal structures, agricultural buildings |
| Relative cost per ton (FOB Tianjin) | Baseline | +12–18% |
As the table shows, AZ150 galvalume delivers three times the corrosion resistance in accelerated tests. For metal roofing coil used in coastal or high‑humidity regions, the extra investment in AZ150 pays back through reduced maintenance and replacement costs. ChinaCNU Steel supplies both grades with ISO certified quality control, ensuring consistent coating adhesion and spangle appearance.
When to Choose AZ50 vs AZ150: Application Guide
Selecting between galvalume steel coil AZ50 vs AZ150 depends on your project’s environment, fabrication requirements, and budget. Here are the most common scenarios based on our 15+ years export experience.
AZ50: Best for Interior and Light‑Duty Exteriors
AZ50 is the economical choice for applications where the coil is not directly exposed to weather. Examples include HVAC ductwork, ceiling panels, interior partitions, and temporary roofing. Because the coating is thinner, AZ50 aluzinc steel coil bends and stamps more easily without cracking—ideal for complex profiles. For buyers with a MOQ 25 tons, AZ50 offers the lowest FOB pricing per ton.
AZ150: The Standard for Long‑Life Roofing and Siding
For permanent metal roofing coil installations—especially in coastal, industrial, or agricultural zones—AZ150 is the industry benchmark. The thicker coating withstands salt fog, acid rain, and UV degradation for decades. ChinaCNU Steel’s AZ150 galvalume is commonly specified for warehouse roofs, livestock barns, and solar panel mounting structures. Our Qingdao factory can supply AZ150 in thicknesses from 0.3 mm to 2.0 mm, with ISO certified tensile and yield properties.
Why ChinaCNU Steel Is Your Trusted Galvalume Supplier China
With 15+ years export to over 50 countries, ChinaCNU Steel has built a reputation for consistent quality and reliable delivery. Our Qingdao factory operates advanced continuous hot‑dip coating lines that produce galvalume steel coil AZ50 vs AZ150 to ASTM A792, EN 10147, and JIS G3321 standards. Every coil is tested for coating weight, adhesion, and surface finish before shipment.
We offer competitive FOB pricing with flexible payment terms and a strict MOQ 25 tons per specification. Whether you need slit coils, sheets, or custom lengths, our team provides technical support to match the right grade to your project. Our ISO certified quality management system ensures traceability from raw material to final packing.
Frequently Asked Questions
1. Can AZ50 be used for roofing in coastal areas?
We do not recommend AZ50 for direct coastal exposure. The thin coating (50 g/m²) will show red rust within 3–5 years in salt‑laden air. For coastal roofing, always choose AZ150 galvalume or a thicker coating grade.
2. What is the price difference between AZ50 and AZ150 per ton?
Based on current FOB pricing from our Qingdao factory, AZ150 typically costs 12–18% more than AZ50. The exact difference depends on thickness, width, and order volume. Contact ChinaCNU Steel for a live quote with your specifications.
3. Does AZ150 still form well for roll‑forming machines?
Yes. Although AZ150 has a thicker coating, modern roll‑formers handle it without issue. The coating is ductile and adheres well during bending. For very tight radii (e.g., 0.5 mm inner bend), we recommend testing a sample first.
4. How do I verify the coating weight of AZ50 or AZ150?
ChinaCNU Steel provides mill test certificates (MTC) with every coil. The coating weight is verified by gravimetric analysis per ASTM A792. You can also request third‑party inspection at the Qingdao factory before shipment.
5. What is the MOQ for galvalume steel coil from ChinaCNU Steel?
Our standard MOQ 25 tons per specification. For mixed containers (e.g., AZ50 and AZ150 in one order), we can accommodate with a minimum of 10 tons per grade. We also support trial orders for new buyers.
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