Stainless Steel HC
UNS J92605 · ASTM A297 Grade HC
HC (UNS J92605, ASTM A297 Grade HC) is a 26-30Cr heat- and corrosion-resistant cast ferritic alloy for furnace and combustion equipment exposed to oxidizing atmospheres up to about 1090 °C.
Reference datasheet — HC 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 F condition
HC tempers and conditions
HC is supplied in 4 conditions, soft to hard. F is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Stress relieved | Choose for dimensionally critical or heavily machined castings to relieve casting and welding stresses; slightly softer, marginally more ductile. | 420 | 640 | 14 | 195 HB | 2.2 % IACS |
FDefault As fabricated | Standard supply condition for furnace hardware; used directly after cleaning and stress relief of risers. | 450 | 690 | 12 | 205 HB | 2.2 % IACS |
Centrifugally cast | Pick for radiant tubes, rolls and cylindrical retorts needing sounder, finer-grained walls than static sand castings. | 470 | 720 | 14 | 210 HB | 2.2 % IACS |
After prolonged high-temperature service exposure | Design reference for parts already in service: strength holds up but room-temperature toughness and ductility collapse from sigma-phase and 475 °C embrittlement. | 520 | 720 | 2 | 20 HRC | 2.2 % IACS |
Supply forms, finishes and certifications
Ways HC is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
A297-MIN | A297 minimum | Certification |
What is HC?
HC (UNS J92605, ASTM A297 Grade HC) is a 26-30Cr heat- and corrosion-resistant cast ferritic alloy for furnace and combustion equipment exposed to oxidizing atmospheres up to about 1090 °C. Typical values are 450 MPa yield, 690 MPa tensile, 12% elongation and 205 HB; it is ordered as-cast (F), to A297 minimums, stress relieved, aged or centrifugally cast. Low nickel limits creep strength and leaves the alloy brittle at room temperature after high-temperature exposure, and the coarse-grained HAZ after welding is crack-sensitive. Grade HD (28Cr-5Ni) is the next step up when more hot strength is required. HC has a density of 7.6 g/cm³ (0.275 lb/in³), lighter than 98% of stainless steel grades. It melts at 1,385°C (2,525 °F). HC has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 690 MPa (100 ksi) — stronger than 70% of stainless steel grades. Elongation at break is 12% and the elastic modulus is 200 GPa (29 Msi).
What is HC used for?
- furnace parts
- combustion chamber components
- heat treatment fixtures
- kiln hardware
Advantages
- High service temperature — 1,090°C (1,994 °F), better than 93% of stainless steel grades
- Low embodied carbon — 3.8 kg CO₂/kg, better than 77% of stainless steel grades
- Conducts heat well — 21 W/m·K (12.1 BTU/hr·ft·°F), better than 76% of stainless steel grades
Limitations
- Limited formability — 8/100, worse than 97% of stainless steel grades
- Hard to polish — 45/100, worse than 96% of stainless steel grades
- Limited ductility — 12%, worse than 95% of stainless steel grades
- Difficult to weld — 30/100, worse than 88% of stainless steel grades
HC properties
Typical room-temperature values for HC-F; bars are the position among stainless steel grades.
Physical3
HC has a density of 7.6 g/cm³ (0.275 lb/in³), lighter than 98% of stainless steel grades. It melts at 1,385°C (2,525 °F).
Mechanical15
HC has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 690 MPa (100 ksi) — stronger than 70% of stainless steel grades. Elongation at break is 12% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
HC is rated for continuous service to 1,090°C (1,994 °F). It conducts heat at 21 W/m·K (12.1 BTU/hr·ft·°F), better than 76% of stainless steel grades. Thermal expansion is 10.8 µm/m·K (6 µin/in·°F).
Electrical3
HC conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 58% of stainless steel grades.
Sustainability4
Producing a kilogram of HC takes about 55 MJ of energy and emits 3.8 kg of CO₂ — more than 50% of stainless steel grades. Typical recycled content is 75%.
Manufacturability8
HC's machinability is poor (32/100, worse than 62% of stainless steel grades); weldability poor (30/100); formability not recommended (8/100).
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 stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. HC is highlighted; hover a dot for its name, or open the interactive family chart.
Working with HC
Is HC easy to machine?
Machine with rigid setups, sharp carbide tooling, low speed and heavy positive feed to cut under the abrasive Cr-carbide network; avoid dwelling to prevent work hardening.
Can HC be welded?
Weldable with 26Cr-type or high-Ni (ERNiCr) filler using 150–260 °C preheat, low heat input and post-weld anneal near 790 °C to restore some ductility; expect brittle coarse-grained HAZ.
Can HC be formed, bent or molded?
A casting alloy only — sand and investment cast with generous fillets and controlled solidification; no cold forming, and hot working is impractical.
HC 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 |
|---|---|---|
| CASTM A297 max | ≤ 0.5 | 0.35 |
| Cr | 26 – 30 | 28 |
| Ni | ≤ 4 | 1.5 |
| Si | ≤ 2 | 1.2 |
| Mn | ≤ 1 | 0.7 |
| Moresidual, not intentionally added | ≤ 0.5 | |
| P | ≤ 0.04 | |
| S | ≤ 0.04 | |
| Fe | balance |
What surface finishes work on HC?
Shot-blast or pickle plus passivate for scale removal; leave uncoated for furnace service since the self-forming chromia scale is the protective layer — painting and plating are pointless above 500 °C.
Surface treatments FabDigit runs on stainless 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).
Passivation
Organic Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel HC in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- J92605
- ASTM
- A297 Grade HC
How much does HC cost?
HC is a premium-cost stainless steel ($$$), cheaper than about 51% 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.
HC — frequently asked
What is HC used for?
HC is typically used for furnace parts, combustion chamber components, heat treatment fixtures and kiln hardware. In short: low-nickel heat-resisting casting; 1090 °C oxidizing service; brittle after thermal exposure.
What is the yield strength of HC?
HC has a typical yield strength of 450 MPa (65.3 ksi) and a tensile strength of 690 MPa (100 ksi) — stronger than 70% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is HC easy to machine?
Not especially — machinability is rated poor (32/100, worse than 62% of stainless steel grades). Machine with rigid setups, sharp carbide tooling, low speed and heavy positive feed to cut under the abrasive Cr-carbide network; avoid dwelling to prevent work hardening.
Can HC be welded?
Not readily — weldability is rated poor (30/100). Weldable with 26Cr-type or high-Ni (ERNiCr) filler using 150–260 °C preheat, low heat input and post-weld anneal near 790 °C to restore some ductility; expect brittle coarse-grained HAZ.
What surface finishes work on HC?
Shot-blast or pickle plus passivate for scale removal; leave uncoated for furnace service since the self-forming chromia scale is the protective layer — painting and plating are pointless above 500 °C.
Can HC be formed, bent or molded?
A casting alloy only — sand and investment cast with generous fillets and controlled solidification; no cold forming, and hot working is impractical.
What is the maximum service temperature of HC?
HC is rated for continuous use to about 1,090°C (1,994 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between HC-F and HC Aged?
F is the default condition — standard supply condition for furnace hardware; used directly after cleaning and stress relief of risers. Aged: design reference for parts already in service: strength holds up but room-temperature toughness and ductility collapse from sigma-phase and 475 °C embrittlement. Yield strength is 450 MPa in F versus 520 MPa in Aged.
How much does HC cost?
HC is a premium-cost stainless steel ($$$), cheaper than about 51% 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 A297/A297M — Steel Castings, Iron-Chromium and Iron-Chromium-Nickel, Heat Resistant, for General Application — ASTM International (2019)
- ASTM A608/A608M — Centrifugally Cast Iron-Chromium-Nickel High-Alloy Tubing for Pressure Application at High Temperatures — ASTM International (2018)
- ASM Specialty Handbook: Heat-Resistant Materials — Cast Heat-Resistant Alloys (ACI H-series) — ASM International (1997)
- ASM Handbook Vol.1 — Cast Stainless Steels — ASM International (1990)
- Steel Founders' Society of America — High Alloy Data Sheets, Heat Series — SFSA (2004)
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.