Steel A709 HPS100W
ASTM A709 HPS100W
A709 Grade HPS100W is a quenched-and-tempered high-performance weathering steel plate developed for US highway bridge girders needing 100 ksi yield with good weldability.
Reference datasheet — A709 HPS100W is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the QT condition
A709 HPS100W tempers and conditions
A709 HPS100W is supplied in 3 conditions, soft to hard. QT is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
over 65 mm to 100 mm (2-1/2 to 4 in) | Heavy-gauge Q&T plate; ASTM A709 permits reduced 620 MPa minimum yield above 65 mm thickness. | 680 | 780 | 20 | 22 HRC | 6.6 % IACS |
QTDefault Quenched and tempered | Standard supply condition for HPS 100W bridge girder flange and web plates up to 65 mm. | 740 | 830 | 20 | 24 HRC | — |
Cooled from hot working, cold worked and naturally aged | Order with the T (non-fracture-critical) Charpy supplement when the member is redundant but low-temperature service applies. | 740 | 830 | 20 | 24 HRC | 6.6 % IACS |
Supply forms, finishes and certifications
Ways A709 HPS100W is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
F2 | Fracture-critical member CVN certification, Temperature Zone 2 | Certification |
F3 | Fracture-critical member CVN certification, Temperature Zone 3 | Certification |
What is A709 HPS100W?
A709 Grade HPS100W is a quenched-and-tempered high-performance weathering steel plate developed for US highway bridge girders needing 100 ksi yield with good weldability. Default QT properties are 740 MPa yield, 830 MPa tensile, 20 % elongation and about 255 HB (24 HRC); plate is supplied in QT, heavy-thickness and bridge toughness classes (T2, F2, F3). Weldability is high for the strength class (score 72) but formability is low (32), and corrosion protection depends on a stable patina that requires drainage detailing. A514 Grade B covers non-weathering 100 ksi work. A709 HPS100W has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). A709 HPS100W has a yield strength of 740 MPa (107 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 83% of steel grades. Elongation at break is 20% and the elastic modulus is 200 GPa (29 Msi).
What is A709 HPS100W used for?
- bridge girders
- structural weldments
- highway infrastructure
Advantages
- Tough — resists crack growth — 200 MPa·√m (182 ksi·√in), better than 100% of steel grades
- Good corrosion resistance — 26/100, better than 93% of steel grades
- High strength — 740 MPa (107 ksi), better than 83% of steel grades
- Readily welded — 72/100, better than 75% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
- Difficult to machine — 38/100, worse than 80% of steel grades
- Low electrical conductivity — 6.6 % IACS, worse than 76% of steel grades
A709 HPS100W properties
Typical room-temperature values for A709 HPS100W-QT; bars are the position among steel grades.
Physical3
A709 HPS100W has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
A709 HPS100W has a yield strength of 740 MPa (107 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 83% of steel grades. Elongation at break is 20% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
A709 HPS100W is rated for continuous service to 400°C (752 °F). It conducts heat at 38 W/m·K (22 BTU/hr·ft·°F), worse than 69% of steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).
Electrical3
A709 HPS100W conducts electricity at 6.6 % IACS, worse than 76% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (26/100), better than 93% of steel grades.
Sustainability4
Producing a kilogram of A709 HPS100W takes about 31 MJ of energy and emits 2.3 kg of CO₂ — more than 64% of steel grades. Typical recycled content is 30%.
Manufacturability5
A709 HPS100W's machinability is fair (38/100, worse than 80% of steel grades); weldability very good (72/100); formability poor (32/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. A709 HPS100W is highlighted; hover a dot for its name, or open the interactive family chart.
Working with A709 HPS100W
Is A709 HPS100W easy to machine?
Machine as a ~250 HB Q&T plate: rigid setups, carbide inserts at 60–110 m/min, generous feed, plenty of coolant; drill and ream holes rather than punch in fracture-critical members.
Can A709 HPS100W be welded?
Excellent weldability for its strength class — use AWS D1.5 low-hydrogen 100 ksi consumables, control heat input (typically 1.2–2.4 kJ/mm) and preheat/interpass per plate thickness to avoid HAZ softening and hydrogen cracking.
Can A709 HPS100W be formed, bent or molded?
Hot-rolled Q&T plate: cold-form only with large bend radii (≥3–4t transverse to rolling) or press-brake hot; avoid flame straightening above the tempering temperature.
A709 HPS100W chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Clow carbon for weldability | ≤ 0.08 | 0.06 |
| Mn | 0.95 – 1.5 | 1.2 |
| P | ≤ 0.02 | 0.01 |
| Sultra-low S for through-thickness toughness | ≤ 0.01 | 0 |
| Si | 0.15 – 0.35 | 0.25 |
| Cuweathering + precipitation strengthening | 0.9 – 1.2 | 1.05 |
| Ni | 0.65 – 0.9 | 0.8 |
| Cr | 0.45 – 0.7 | 0.6 |
| Mo | 0.4 – 0.65 | 0.5 |
| V | 0.04 – 0.08 | 0.06 |
| Al | 0.02 – 0.05 | 0.03 |
| N | ≤ 0.02 | 0.01 |
| Fe | balance |
What surface finishes work on A709 HPS100W?
Normally used uncoated so a stable weathering patina develops (detail for drainage and avoid chloride splash); where coated, blast to SSPC-SP10 and apply a zinc-rich/epoxy/urethane bridge system.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel A709 HPS100W in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- A709 Grade HPS100W
How much does A709 HPS100W cost?
A709 HPS100W is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
A709 HPS100W — frequently asked
What is A709 HPS100W used for?
A709 HPS100W is typically used for bridge girders, structural weldments and highway infrastructure. In short: weathering 100 ksi bridge plate; best weldability at 100 ksi; bridge toughness classes.
What is the yield strength of A709 HPS100W?
A709 HPS100W has a typical yield strength of 740 MPa (107 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 83% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is A709 HPS100W easy to machine?
Not especially — machinability is rated fair (38/100, worse than 80% of steel grades). Machine as a ~250 HB Q&T plate: rigid setups, carbide inserts at 60–110 m/min, generous feed, plenty of coolant; drill and ream holes rather than punch in fracture-critical members.
Can A709 HPS100W be welded?
Yes — weldability is rated very good (72/100). Excellent weldability for its strength class — use AWS D1.5 low-hydrogen 100 ksi consumables, control heat input (typically 1.2–2.4 kJ/mm) and preheat/interpass per plate thickness to avoid HAZ softening and hydrogen cracking.
What surface finishes work on A709 HPS100W?
Normally used uncoated so a stable weathering patina develops (detail for drainage and avoid chloride splash); where coated, blast to SSPC-SP10 and apply a zinc-rich/epoxy/urethane bridge system.
Can A709 HPS100W be formed, bent or molded?
Hot-rolled Q&T plate: cold-form only with large bend radii (≥3–4t transverse to rolling) or press-brake hot; avoid flame straightening above the tempering temperature.
What is the maximum service temperature of A709 HPS100W?
A709 HPS100W is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between A709 HPS100W-QT and A709 HPS100W-T2?
QT is the default condition — standard supply condition for HPS 100W bridge girder flange and web plates up to 65 mm. T2: order with the T (non-fracture-critical) Charpy supplement when the member is redundant but low-temperature service applies. Yield strength is 740 MPa in QT versus 740 MPa in T2.
How much does A709 HPS100W cost?
A709 HPS100W is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM A709/A709M — Standard Specification for Structural Steel for Bridges — ASTM International (2021)
- AASHTO M 270M/M 270 — Structural Steel for Bridges — AASHTO (2020)
- AWS D1.5/D1.5M Bridge Welding Code — AWS/AASHTO (2020)
- High Performance Steel Designers' Guide (HPS 70W / HPS 100W) — FHWA / AISI (2002)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- AASHTO LRFD Bridge Design Specifications (material constants) — AASHTO (2020)
- Mysteel / SMM — Mysteel (2026)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.