Steel A182 FR
ASTM A182 FR · UNS K22035
ASTM A182 FR (UNS K22035, equivalent to A350 LF3) is a 3.5% nickel low-alloy forging steel engineered for guaranteed notch toughness at cryogenic and low temperatures.
Reference datasheet — A182 FR 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 N+T condition
A182 FR tempers and conditions
A182 FR is supplied in 3 conditions, soft to hard. N+T 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 |
|---|---|---|---|---|---|---|
Normalized | Normalized-only forgings for thin sections where tempering is not required and moderate strength suffices. | 330 | 505 | 27 | 150 HB | 7.5 % IACS |
N+TDefault Normalized and tempered | Standard mill-supplied condition for A182 FR flanges and fittings; best balance of strength and −46 °C notch toughness. | 355 | 520 | 26 | 160 HB | — |
Quenched and tempered | Choose for heavy-section forgings or when the highest low-temperature impact energy and through-thickness properties are needed. | 450 | 585 | 23 | 185 HB | — |
What is A182 FR?
ASTM A182 FR (UNS K22035, equivalent to A350 LF3) is a 3.5% nickel low-alloy forging steel engineered for guaranteed notch toughness at cryogenic and low temperatures. It is used for flanges, valve bodies and fittings in LNG and cold-service piping, with normalized-and-tempered values of 355 MPa yield, 520 MPa tensile, 26% elongation and about 160 HB (84 HRB); impact properties are qualified down to −46 °C. Maximum service temperature is 400 °C and the steel has no inherent corrosion resistance, so coating or plating is required; weldability is good with low-hydrogen consumables and 100–150 °C preheat. For ambient service, a carbon-steel A105 forging is the cheaper choice. A182 FR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,450°C (2,642 °F). A182 FR has a yield strength of 355 MPa (51.5 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 73% of steel grades. Elongation at break is 26% and the elastic modulus is 205 GPa (29.7 Msi).
What is A182 FR used for?
- LNG piping flanges
- Low-temperature valve bodies
- Cold-service fittings
Advantages
- Good corrosion resistance — 22/100, better than 90% of steel grades
- Ductile — tolerates forming and impact — 26%, better than 82% of steel grades
- Tough — resists crack growth — 120 MPa·√m (109.2 ksi·√in), better than 81% of steel grades
A182 FR properties
Typical room-temperature values for A182 FR-N+T; bars are the position among steel grades.
Physical3
A182 FR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,450°C (2,642 °F).
Mechanical15
A182 FR has a yield strength of 355 MPa (51.5 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 73% of steel grades. Elongation at break is 26% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
A182 FR is rated for continuous service to 400°C (752 °F). It conducts heat at 40 W/m·K (23.1 BTU/hr·ft·°F), worse than 64% of steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).
Electrical3
A182 FR conducts electricity at 7.5 % IACS, worse than 67% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (22/100), better than 90% of steel grades.
Sustainability4
Producing a kilogram of A182 FR takes about 26 MJ of energy and emits 2.1 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 30%.
Manufacturability7
A182 FR's machinability is good (58/100, better than 75% of steel grades); weldability good (65/100); formability fair (45/100).
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. A182 FR is highlighted; hover a dot for its name, or open the interactive family chart.
Working with A182 FR
Is A182 FR easy to machine?
Machines like normalized 4130/A350-class steel at ~60 % of AISI 1212; use rigid setups, carbide inserts and moderate speeds — copper content can cause slight gumminess in soft condition.
Can A182 FR be welded?
Weldable with low-hydrogen SMAW/GTAW/SAW using matching or 1–2 %Ni filler; preheat 100–150 °C, control interpass, and PWHT/temper at ~595–650 °C to restore −46 °C notch toughness.
Can A182 FR be formed, bent or molded?
Hot forge at 1050–1200 °C with finishing above 900 °C, then normalize (or quench) and temper; cold forming is limited and should be followed by stress relief.
A182 FR 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 |
|---|---|---|
| Cmax per ASTM A182 Grade FR | ≤ 0.2 | 0.15 |
| Mn | 0.4 – 1.06 | 0.8 |
| Si | 0.15 – 0.3 | 0.22 |
| Pimpurity limit | ≤ 0.05 | 0.02 |
| Simpurity limit | ≤ 0.05 | 0.01 |
| Niprovides low-temperature toughness | 1.6 – 2.24 | 1.9 |
| Cr | 0.7 – 1.1 | 0.9 |
| Cuatmospheric corrosion resistance | 0.75 – 1.25 | 1 |
| Fe | balance | — |
What surface finishes work on A182 FR?
Not anodizable — protect with shop primer, epoxy/zinc-rich paint, hot-dip galvanizing or electroless nickel; bare surfaces will form a weathering patina outdoors.
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 A182 FR in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- K22035
- ASTM
- A350 LF3
How much does A182 FR cost?
A182 FR is a standard-cost steel ($$), cheaper than about 71% 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.
A182 FR — frequently asked
What is A182 FR used for?
A182 FR is typically used for LNG piping flanges, low-temperature valve bodies and cold-service fittings. In short: cryogenic-toughness nickel forging; best weldability in family; qualified at −46 °C.
What is the yield strength of A182 FR?
A182 FR has a typical yield strength of 355 MPa (51.5 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 73% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is A182 FR easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Machines like normalized 4130/A350-class steel at ~60 % of AISI 1212; use rigid setups, carbide inserts and moderate speeds — copper content can cause slight gumminess in soft condition.
Can A182 FR be welded?
Yes — weldability is rated good (65/100). Weldable with low-hydrogen SMAW/GTAW/SAW using matching or 1–2 %Ni filler; preheat 100–150 °C, control interpass, and PWHT/temper at ~595–650 °C to restore −46 °C notch toughness.
What surface finishes work on A182 FR?
Not anodizable — protect with shop primer, epoxy/zinc-rich paint, hot-dip galvanizing or electroless nickel; bare surfaces will form a weathering patina outdoors.
Can A182 FR be formed, bent or molded?
Hot forge at 1050–1200 °C with finishing above 900 °C, then normalize (or quench) and temper; cold forming is limited and should be followed by stress relief.
What is the maximum service temperature of A182 FR?
A182 FR 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 A182 FR N+T and A182 FR-N?
N+T is the default condition — standard mill-supplied condition for A182 FR flanges and fittings; best balance of strength and −46 °C notch toughness. N: normalized-only forgings for thin sections where tempering is not required and moderate strength suffices. Yield strength is 355 MPa in N+T versus 330 MPa in N.
How much does A182 FR cost?
A182 FR is a standard-cost steel ($$), cheaper than about 71% 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 A182/A182M — Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Forged Fittings, and Valves and Parts — ASTM International (2023)
- ASTM A350/A350M — Carbon and Low-Alloy Steel Forgings Requiring Notch Toughness Testing (Grade LF9 comparison) — ASTM International (2022)
- ASME BPVC Section II Part D — Physical and allowable stress data for low-alloy steels — ASME (2023)
- ASME B16.5 / B16.34 — Pipe Flanges and Valve Material Groups — ASME (2020)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.13A — Corrosion: Fundamentals, Testing, and Protection (weathering steels) — ASM International (2003)
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.