20 Ga Aluminized Steel
20 Ga aluminized steel is a versatile specification widely used across automotive, HVAC, and heating equipment industries. With a nominal thickness of 0.91 mm, standard widths up to 1524 mm, and flexible sheet or coil formats, it provides excellent corrosion resistance, formability, and heat durability.
- Description
Description
20 gauge aluminized steel refers to aluminized steel sheet with a nominal thickness of 20 gauge, commonly used in automotive, HVAC, heating appliances, and industrial fabrication. The sheet is coated with an aluminum or aluminum–silicon alloy layer to improve corrosion resistance, heat reflectivity, and oxidation performance.
20 gauge is one of the most widely used thicknesses because it offers a strong balance between strength, workability, and heat resistance.
20 Gauge Thickness and Metric Conversion
In aluminized steel, 20 Ga corresponds to the following typical thickness:
| Gauge (Ga) | Inch (in) | Millimeter (mm) |
|---|---|---|
| 20 Ga | 0.0359 in | 0.91 mm |
Thickness may vary slightly based on manufacturing tolerance.
Common Width Options for 20 Ga Aluminized Steel
Aluminized steel sheet is available in several standard widths to support different processing needs:
24 in (610 mm)
36 in (914 mm)
40 in (1016 mm)
48 in (1219 mm)
60 in (1524 mm)
Custom widths can also be offered depending on coil processing capability.
Standard Lengths (Sheets) or Coil Supply
20 Ga aluminized steel is commonly supplied as:
1. Sheets
Typical cut-to-length sizes include:
48″ × 96″ (1219 × 2438 mm)
48″ × 120″ (1219 × 3048 mm)
36″ × 96″ (914 × 2438 mm)
36″ × 120″ (914 × 3048 mm)
Custom lengths available up to 6000 mm depending on processing lines
2. Coils
Inner diameter (ID): 508 mm or 610 mm
Coil weight: Based on thickness and width; can be light or full-width coils
Aluminized Steel Types Available in 20 Gauge
20 Ga aluminized steel is typically produced in two types:
| Type | Coating | Key Features |
|---|---|---|
| Type 1 (Al-Si coating) | Aluminum–Silicon alloy (approx. 5–11% Si) | Higher heat resistance, excellent oxidation resistance |
| Type 2 (Pure Al coating) | Nearly pure aluminum | Superior atmospheric corrosion resistance |
Both types are widely used depending on whether heat resistance or corrosion resistance is the main priority.
Coating Weight Options for 20 Ga Aluminized Steel
Typical coating weight ranges:
| Coating Designation | Total Aluminum Coating (Both Sides) | Application Notes |
|---|---|---|
| T1-40 | ~120 g/m² | Automotive exhaust, heaters |
| T1-25 | ~75 g/m² | HVAC, ductwork, household appliances |
| T2-40 | ~120 g/m² | Outdoor structures, chimneys |
| T2-25 | ~75 g/m² | General atmospheric protection |
Available coating weights depend on region and production standards.
Dimensional Tolerances for 20 Gauge Aluminized Steel
Typical tolerances (may vary by mill standard):
Thickness tolerance: ±0.04–0.06 mm
Width tolerance: ±2–3 mm
Flatness tolerance: Depends on sheet width and length
Coating weight tolerance: As per ASTM or EN standard requirements
These tolerances ensure stability during forming, stamping, bending, and welding.
Common Applications of 20 Ga Aluminized Steel
Because of its balanced thickness, 20 gauge aluminized steel is widely used in:
Automotive exhaust components
Heat shields and thermal covers
Furnace and oven parts
HVAC ducting and ventilation systems
Fireplace and heating equipment
Water heaters and combustion chambers
Industrial fabrications and enclosures
It provides consistent performance under moderate to high temperatures.
