Stainless Steel 1.4958 CR-A
Finish state
EN 1.4958 · UNS N08810 · also Incoloy 800H
CR-A = cold rolled sheet/strip, annealed
Thin gauge sheet and strip for furnace muffles, radiant tubes and formed components requiring a smooth surface.
Values for the CR-A condition
Other 1.4958 tempers and conditions
1.4958 is listed in 6 conditions; see the grade overview at 1.4958.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Forged and solution annealed | Heavy forged sections for headers, flanges and pigtail fittings in reformer service; grain size controlled for creep design. | 215 | 510 | 40 | 145 HB | 1.7 % IACS |
SADefault Solution annealed | Standard supply condition for plate, tube and pipe used in creep-range service; gives the coarse grain required for 800H creep properties. | 220 | 520 | 45 | 140 HB | — |
Cold drawn then solution annealed bar/tube | Precision seamless tube and bright bar restored to full 800H creep condition after cold drawing. | 225 | 520 | 45 | 140 HB | 1.7 % IACS |
Hot rolled plate, solution annealed and pickled | Heavy plate for furnace retorts, headers and pressure parts; slightly higher strength than thin annealed product. | 240 | 540 | 42 | 150 HB | 1.7 % IACS |
CR-AThis page Cold rolled sheet/strip, annealed | Thin gauge sheet and strip for furnace muffles, radiant tubes and formed components requiring a smooth surface. | 250 | 550 | 45 | 145 HB | 1.7 % IACS |
Cold drawn | Choose for close-tolerance bar and small-bore tubing where higher room-temperature strength and better surface finish are wanted; not for long-term creep service without re-anneal. | 400 | 620 | 30 | 11 HRC | 1.7 % IACS |
What is 1.4958 CR-A?
1.4958 CR-A is 1.4958 supplied in the CR-A condition — thin gauge sheet and strip for furnace muffles, radiant tubes and formed components requiring a smooth surface. 1.4958 CR-A has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 91% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 196 GPa (28.4 Msi). 1.4958 CR-A has a density of 7.94 g/cm³ (0.287 lb/in³), heavier than 78% of stainless steel grades. It melts at 1,357°C (2,475 °F). SA is the default condition FabDigit quotes; CR-A is available on request or by drawing note.
Advantages
- High service temperature — 1,100°C (2,012 °F), better than 96% of stainless steel grades
- Forms and bends easily — 75/100, better than 87% of stainless steel grades
- Readily welded — 80/100, better than 80% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- Poor heat conductor — 11.5 W/m·K (6.64 BTU/hr·ft·°F), worse than 97% of stainless steel grades
- High embodied carbon — 6.8 kg CO₂/kg, worse than 95% of stainless steel grades
- Low electrical conductivity — 1.7 % IACS, worse than 93% of stainless steel grades
- Low strength — 250 MPa (36.3 ksi), worse than 91% of stainless steel grades
1.4958 CR-A properties
Typical room-temperature values for 1.4958 CR-A; 22 are specific to this condition. Other listed values are 1.4958 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4958 CR-A has a density of 7.94 g/cm³ (0.287 lb/in³), heavier than 78% of stainless steel grades. It melts at 1,357°C (2,475 °F).
Mechanical15
1.4958 CR-A has a yield strength of 250 MPa (36.3 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 91% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 196 GPa (28.4 Msi).
Thermal5
1.4958 CR-A is rated for continuous service to 1,100°C (2,012 °F). It conducts heat at 11.5 W/m·K (6.64 BTU/hr·ft·°F), worse than 97% of stainless steel grades. Thermal expansion is 14.4 µm/m·K (8 µin/in·°F).
Electrical3
1.4958 CR-A conducts electricity at 1.7 % IACS, worse than 93% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (70/100), better than 68% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4958 CR-A takes about 90 MJ of energy and emits 6.8 kg of CO₂ — more than 94% of stainless steel grades. Typical recycled content is 40%.
Manufacturability7
1.4958 CR-A's machinability is poor (30/100, worse than 70% of stainless steel grades); weldability very good (80/100); formability very good (75/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4958 CR-A
Is 1.4958 easy to machine?
Machine like a tough austenitic: rigid setup, positive-rake carbide, low speed / heavy positive feed, flood coolant and no dwelling — the alloy work-hardens rapidly and is gummy.
Can 1.4958 be welded?
Readily welded by GTAW/GMAW/SMAW with Ni-Cr-Nb fillers (ERNiCr-3 / ENiCrFe-2); no preheat needed, keep interpass low and heat input moderate, post-weld heat treatment normally unnecessary.
Can 1.4958 be formed, bent or molded?
Good cold formability but ~1.5× the forming loads of 304 and high springback; hot work at 950–1200 °C and re-solution anneal at 1100–1180 °C to restore the coarse grain required for 800H creep properties.
What surface finishes work on 1.4958?
Pickle in HNO₃–HF or bright anneal to remove the tenacious Cr/Al/Ti oxide before service; can be ground and polished to a bright finish, not anodizable, plating rarely used.
1.4958 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 |
|---|---|---|
| Ccontrolled carbon distinguishes 800H from 800 (EN 1.4958 permits 0.03–0.08) | 0.05 – 0.1 | 0.07 |
| Si | ≤ 1 | 0.4 |
| Mn | ≤ 1.5 | 0.8 |
| P | ≤ 0.03 | — |
| S | ≤ 0.02 | — |
| Cr | 19 – 23 | 21 |
| Ni | 30 – 35 | 32 |
| Al | 0.15 – 0.6 | 0.4 |
| Ti | 0.15 – 0.6 | 0.4 |
| Cu | ≤ 0.75 | — |
| Febalance, 39.5 % min per ASTM B409/B408 | ≥ 39.5 (balance) | — |
1.4958 CR-A — frequently asked
What is 1.4958 CR-A used for?
1.4958 CR-A is typically used for reformer tubes, cracking furnace components, heat exchanger tubing and power generation piping. In short: creep-rated Alloy 800; coarse-grain 800H condition; pressure service to 1100 °C.
What is the yield strength of 1.4958 CR-A?
1.4958 CR-A has a typical yield strength of 250 MPa (36.3 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 91% of stainless steel grades. Strength varies by condition: see the 6 listed tempers.
Is 1.4958 CR-A easy to machine?
Not especially — machinability is rated poor (30/100, worse than 70% of stainless steel grades). Machine like a tough austenitic: rigid setup, positive-rake carbide, low speed / heavy positive feed, flood coolant and no dwelling — the alloy work-hardens rapidly and is gummy.
Can 1.4958 CR-A be welded?
Yes — weldability is rated very good (80/100). Readily welded by GTAW/GMAW/SMAW with Ni-Cr-Nb fillers (ERNiCr-3 / ENiCrFe-2); no preheat needed, keep interpass low and heat input moderate, post-weld heat treatment normally unnecessary.
What surface finishes work on 1.4958 CR-A?
Pickle in HNO₃–HF or bright anneal to remove the tenacious Cr/Al/Ti oxide before service; can be ground and polished to a bright finish, not anodizable, plating rarely used.
Can 1.4958 CR-A be formed, bent or molded?
Good cold formability but ~1.5× the forming loads of 304 and high springback; hot work at 950–1200 °C and re-solution anneal at 1100–1180 °C to restore the coarse grain required for 800H creep properties.
What is the maximum service temperature of 1.4958 CR-A?
1.4958 CR-A is rated for continuous use to about 1,100°C (2,012 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4958-SA and 1.4958-CD?
SA is the default condition — standard supply condition for plate, tube and pipe used in creep-range service; gives the coarse grain required for 800H creep properties. CD: choose for close-tolerance bar and small-bore tubing where higher room-temperature strength and better surface finish are wanted; not for long-term creep service without re-anneal. Yield strength is 220 MPa in SA versus 400 MPa in CD.
Sources
- ASTM B409 / B408 / B564 — Ni-Fe-Cr alloy plate, bar and forgings (UNS N08810) — ASTM International (2021)
- EN 10095 — Heat resisting steels and nickel alloys (X5NiCrAlTi31-20, 1.4958) — CEN (1999)
- INCOLOY alloy 800H & 800HT product datasheet — Special Metals Corporation (2004)
- ASM Handbook Vol. 1 — Heat-Resistant Alloys — ASM International (1990)
- ASME BPVC Section II Part D — allowable stresses for N08810 — ASME (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.