ASME SA709 Grade HPS50W High-Performance Weathering Structural Steel Coil
ASME SA709 Grade HPS50W High-Performance Weathering Structural Steel Coil
Detailed properties, chemical composition, mechanical and thermal data for ASME SA709/SA709M Grade HPS50W high-strength low-alloy weathering steel coil used in structural and bridge engineering.
Hot rolling, controlled rolling (TMCP), normalizing possible
- Phone : +8618037372205
- Email : [email protected]
- WhatsApp: Contact via Whtsapp
- WeChat: +8618037372205
ASME SA709 Grade HPS50W High-Performance Weathering Structural Steel Coil Introduction
ASME SA709/SA709M Grade HPS50W is a high-performance structural steel grade within the ASME SA709 standard for carbon and low-alloy high-strength steel. It is specifically designed for bridge construction and other structural applications where enhanced atmospheric corrosion resistance (weathering) and superior weldability are required. The "HPS" designation indicates it meets toughness and chemical composition requirements of the AASHTO HPS (High Performance Steel) program. This grade offers a minimum yield strength of 50 ksi (345 MPa) and exhibits a protective rust-like patina when exposed to the environment, eliminating the need for painting in many cases. Typical delivery condition is hot-rolled or thermomechanically controlled rolled (TMCP).
ASME SA709 Grade HPS50W High-Performance Weathering Structural Steel Coil Chemical Composition
The steel is microalloyed with vanadium and aluminum for fine grain structure, combined with copper, chromium and nickel for enhanced atmospheric corrosion resistance. Low carbon and restricted phosphorus and sulfur ensure excellent weldability and toughness. The following limits apply to heat analysis as per ASME SA709/SA709M for Grade HPS50W.
| Element | Standard Value | Remarks |
|---|---|---|
| Carbon (C) | ≤ 0.11 % | |
| Manganese (Mn) | 1.10 – 1.35 % | |
| Phosphorus (P) | ≤ 0.020 % | |
| Sulfur (S) | ≤ 0.006 % | |
| Silicon (Si) | 0.30 – 0.50 % | |
| Copper (Cu) | 0.25 – 0.40 % | |
| Nickel (Ni) | 0.25 – 0.40 % | |
| Chromium (Cr) | 0.45 – 0.70 % | |
| Vanadium (V) | 0.04 – 0.08 % | |
| Aluminum (Al) | 0.010 – 0.040 % | |
| Nitrogen (N) | ≤ 0.015 % |
ASME SA709 Grade HPS50W High-Performance Weathering Structural Steel Coil Thermal and Electrical Physical Properties
Physical properties are typical for low-alloy structural steels and may vary slightly with processing. These values are for room temperature unless otherwise noted and are provided for general engineering purposes.
| Property | Typical Value | Unit | Condition / Temperature |
|---|---|---|---|
| Density (ρ) | 7.85 | g/cm³ | 20 °C |
| Elastic Modulus (E) | 200 | GPa | Room temperature |
| Shear Modulus (G) | 80 | GPa | Room temperature |
| Poisson's Ratio (ν) | 0.3 | Room temperature | |
| Thermal Expansion Coefficient (α) | 12.0 | μm/m·°C | 20 – 100 °C |
| Thermal Conductivity (λ) | 45 | W/m·K | 20 °C |
| Specific Heat Capacity | 480 | J/kg·K | 20 °C |
| Electrical Resistivity (ρ_e) | 0.20 | μΩ·m | 20 °C |
ASME SA709 Grade HPS50W High-Performance Weathering Structural Steel Coil Mechanical Properties
Tensile and yield strength requirements depend on product thickness. Elongation is measured on 200 mm (8 in.) gauge for sheets/plates and on 50 mm (2 in.) gauge for shapes. Bend test is performed per ASTM A6/A6M. Notch toughness (KV) is an optional supplementary requirement typically specified for bridge applications (e.g., 27 J at -20°C).
| Property | Required Value | Unit | Test Condition |
|---|---|---|---|
| Yield Strength (ReH) | ≥ 345 | MPa | Thickness ≤ 100 mm |
| Tensile Strength (Rm) | ≥ 485 | MPa | Thickness ≤ 100 mm |
| Elongation (A) | ≥ 18 | % | Gauge 200 mm, Thickness ≤ 100 mm |
| Elongation (A) | ≥ 21 | % | Gauge 50 mm, Thickness ≤ 100 mm |
| Bend Test | d = 1.5t | Thickness ≤ 20 mm | |
| Bend Test | d = 2.0t | Thickness > 20 mm to 25 mm | |
| Bend Test | d = 2.5t | Thickness > 25 mm to 50 mm | |
| Impact Toughness (KV) | ≥ 27 (typical) | J | At specified temperature (e.g., -20°C), optional |
ASME SA709 Grade HPS50W High-Performance Weathering Structural Steel Coil Fully Equivalent Material Standards and Substitute Grades
| Country/Region | Standard | Grade | Remarks |
|---|---|---|---|
| United States | ASTM A709/A709M | Grade HPS50W | Identical chemical and mechanical requirements; SA709 adopted from ASTM A709. |
ASME SA709 Grade HPS50W High-Performance Weathering Structural Steel Coil Application Introduction
ASME SA709 HPS50W is primarily used in structural applications that demand high strength, excellent weldability, and atmospheric corrosion resistance. The grade is a preferred material for modern steel bridges where lifecycle cost reduction through elimination of paint systems is desired. It can be fabricated into a wide range of components using standard shop practices.
Product Applications: Bridge girders, trusses and arches, Highway signage and gantry structures, Architectural exposed steel frames, Welded structural columns and beams, Stiffened plate panels, Tubular sections for structures
Processed into products: Welded built-up I- and box-girders, Stiffeners and cross-frames, Bolted connections and splice plates, Bearing plates and base plates, Diaphragms and lateral bracings, Stay-in-place formwork decks
Application industries: Bridge and highway construction, Heavy civil engineering, Building and infrastructure, Transmission and telecommunication towers, Shipbuilding (limited to non-marine exposure structures), Industrial plants and equipment
ASME SA709 Grade HPS50W High-Performance Weathering Structural Steel Coil Similar or Comparable Substitute Materials
The following grades are not identical but offer comparable strength and weathering characteristics. Direct substitution requires verification of chemical ranges and supplementary requirements.
| Country/Region | Standard | Grade | Remarks |
|---|---|---|---|
| United States | ASTM A709/A709M | Grade 50W (non-HPS) | Similar strength and weathering; HPS grade offers tighter chemistry and mandatory toughness. |
| European Union | EN 10025-5 | S355J2W+N or +AR | Similar yield strength and weathering; different alloy system, may require weldability adjustments. |
| Japan | JIS G 3114 | SMA490AW | Weathering steel with comparable strength; check toughness availability. |
| China | GB/T 4171 | Q355NH | Comparable weathering steel with min. yield 355 MPa; not HPS microalloyed. |
Notes:
- Atmospheric corrosion resistance relies on the formation of a protective oxide layer; suitable for most environments except marine immersion or heavily industrial acidic conditions.
- Preheat and interpass temperature control are recommended for welding thick sections to avoid hydrogen-induced cracking.
- Optional Supplementary Requirements (e.g., S5 for Charpy V-notch testing, S18 for maximum carbon equivalent) are commonly invoked in bridge specifications.
- Mechanical properties of hot-rolled coils may vary through thickness; property verification testing should follow the governing SA709 standard.
- Share
