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Stainless Steel CK35MN-SA (Solution annealed)

Heat-treated state

ASTM CK35MN

Choose when maximum ductility, toughness and aqueous corrosion resistance are needed before service; dissolves the as-cast carbide network.

High cost $$$$

Values for the SA condition

Other CK35MN tempers and conditions

CK35MN is listed in 4 conditions; see the grade overview at CK35MN.

Compare all 4 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
SAThis page
Solution annealed
Choose when maximum ductility, toughness and aqueous corrosion resistance are needed before service; dissolves the as-cast carbide network.23048038170 HB2 % IACS
Statically sand/investment cast shape
Standard route for valve bodies, grates, fixtures and complex furnace hardware where section thickness varies.24549530183 HB2 % IACS
ACDefault
Spheroidize annealed
Standard supply condition for heat-resistant service — carbides in the as-cast network actually aid creep strength.25050030185 HB2 % IACS
Stress relieved
Use on large or welded castings to relieve residual stress and reduce distortion before machining; does not restore ductility.25049526187 HB2.1 % IACS

What is CK35MN-SA?

CK35MN-SA is CK35MN heat treated to SA — choose when maximum ductility, toughness and aqueous corrosion resistance are needed before service; dissolves the as-cast carbide network. CK35MN-SA has a yield strength of 230 MPa (33.4 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 99% of stainless steel grades. Elongation at break is 38% and the elastic modulus is 193 GPa (28 Msi). CK35MN-SA has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,370°C (2,498 °F). AC is the default condition FabDigit quotes; SA is available on request or by drawing note.

Advantages

  • High service temperature — 1,050°C (1,922 °F), better than 91% of stainless steel grades

Limitations

  • Low strength — 230 MPa (33.4 ksi), worse than 99% of stainless steel grades
  • Hard to polish — 55/100, worse than 89% of stainless steel grades
  • Difficult to weld — 45/100, worse than 79% of stainless steel grades
  • Low electrical conductivity — 2 % IACS, worse than 77% of stainless steel grades

CK35MN-SA properties

Typical room-temperature values for CK35MN-SA; 23 are specific to this condition. Other listed values are CK35MN reference data and may not represent this condition. Bars are the position among stainless steel grades.

Physical3

CK35MN-SA has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,370°C (2,498 °F).

Density7.75 g/cm³0.28 lb/in³
Melting Point (Solidus)1,370°C2,498 °F
Liquidus Temperature1,420°C2,588 °F

Mechanical15

CK35MN-SA has a yield strength of 230 MPa (33.4 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 99% of stainless steel grades. Elongation at break is 38% and the elastic modulus is 193 GPa (28 Msi).

Elastic (Young's) Modulus193 GPa28 Msi
Shear Modulus75 GPa10.9 Msi
Bulk Modulus155 GPa22.5 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)480 MPa69.6 ksi
Yield Strength (0.2% offset)230 MPa33.4 ksi
Elongation at Break38%
Reduction in Area42%
Shear Strength300 MPa43.5 ksi
Fatigue Strength (Endurance Limit)195 MPa28.3 ksi
Fracture Toughness (K_IC)120 MPa·√m109 ksi·√in
Charpy V-Notch Impact (RT)55 J40.6 ft·lbf
Hardness, Brinell170 HB
Hardness, Rockwell B85 HRB
Hardness, Vickers178 HV

Thermal6

CK35MN-SA is rated for continuous service to 1,050°C (1,922 °F). It conducts heat at 14.5 W/m·K (8.38 BTU/hr·ft·°F), worse than 72% of stainless steel grades. Thermal expansion is 15.9 µm/m·K (8.83 µin/in·°F).

Thermal Conductivity14.5 W/m·K8.4 BTU/hr·ft·°F
Specific Heat Capacity500 J/kg·K0.12 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)15.9 µm/m·K8.8 µin/in·°F
Latent Heat of Fusion270 J/g116 BTU/lb
Max Service Temperature (continuous)1,050°C1,922 °F
Min Service Temperature-100°C-148 °F

Electrical3

CK35MN-SA conducts electricity at 2 % IACS, worse than 77% of stainless steel grades.

Electrical Conductivity2 % IACS
Electrical Resistivity8.5×10⁻⁷ Ω·m33.5 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is good (62/100), worse than 52% of stainless steel grades.

Galvanic Potential (seawater, vs SCE)-0.1 V
Corrosion ResistanceGood62/100
Chemical Resistance SummaryExcellent resistance to dry high-temperature oxidation, combustion gases and low-sulphur flue gas; good in hot nitric/oxidizing acids. Not recommended for chlorides or reducing sulphidizing atmospheres, and intergranular attack is likely after service in the 600–900 °C carbide-precipitation range.

Sustainability4

Producing a kilogram of CK35MN-SA takes about 60 MJ of energy and emits 4.5 kg of CO₂ — more than 70% of stainless steel grades. Typical recycled content is 65%.

Embodied Energy (primary production)60 MJ/kg25,795 BTU/lb
Embodied Carbon (primary production)4.5 kg CO₂/kg
Embodied Water180 L/kg21.6 gal/lb
Typical Recycled Content65%

Manufacturability8

CK35MN-SA's machinability is poor (31/100, worse than 65% of stainless steel grades); weldability fair (45/100); formability fair (35/100).

MachinabilityPoor31/100
Machinability Rating (AISI 1212 = 100 %)33%
WeldabilityFair45/100
Formability (cold)Fair35/100
CastabilityVery good70/100
Brazeability / SolderabilityFair45/100
PolishabilityGood55/100
Anodizing Responsen/a — ferrous alloy; use passivation or high-temperature aluminizing instead

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with CK35MN-SA

Is CK35MN easy to machine?

Rigid setups, low speed with heavy positive feed, sharp carbide or ceramic tooling and flood coolant; the work-hardening austenite plus interdendritic carbides cause rapid edge wear, so avoid dwelling and interrupted light cuts.

Can CK35MN be welded?

Weldable with matching 25Cr-20Ni (ER310/E310-type) filler using low heat input, small stringer beads and interpass temperature control; fully austenitic ferrite-free weld metal is hot-crack sensitive and the high-carbon base is prone to HAZ carbide precipitation.

Can CK35MN be formed, bent or molded?

A casting grade only — not intended for cold forming; design generous fillets, uniform sections and adequate risers, allow ~2 % solidification shrinkage and avoid hot-tear-prone sharp corners.

What surface finishes work on CK35MN?

Grit blast plus pickle/passivate to remove casting scale; shot-peening or grinding improves fatigue, and aluminizing or diffusion coating extends life above 1000 °C in sulphur-bearing gas.

CK35MN 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.

ElementSpec limit (wt %)Nominal
Chigh carbon for creep strength; verify range against the current ASTM A351/A743 edition0.25 – 0.350.3
Mnmanganese-alloyed feature of this grade (partial Ni substitute / austenite stabilizer)1.5 – 42.5
Si≤ 1.51
CrCK-family chromium level, as CK2023 – 2725
Ni18 – 2220
Moresidual only≤ 0.50.2
Nnitrogen may be specified to strengthen the austenite≤ 0.20.1
P≤ 0.04—
S≤ 0.04—
Febalance—

CK35MN-SA — frequently asked

What is CK35MN-SA used for?

CK35MN-SA is typically used for high-temperature furnace castings, heat-resistant process equipment, heat treatment fixtures and trays, furnace rollers and rails, radiant tube and burner parts and kiln fittings. In short: manganese-alloyed CK20 substitute; lower nickel content; 1050 °C oxidation service.

What is the yield strength of CK35MN-SA?

CK35MN-SA has a typical yield strength of 230 MPa (33.4 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 99% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.

Is CK35MN-SA easy to machine?

Not especially — machinability is rated poor (31/100, worse than 65% of stainless steel grades). Rigid setups, low speed with heavy positive feed, sharp carbide or ceramic tooling and flood coolant; the work-hardening austenite plus interdendritic carbides cause rapid edge wear, so avoid dwelling and interrupted light cuts.

Can CK35MN-SA be welded?

With care — weldability is rated fair (45/100). Weldable with matching 25Cr-20Ni (ER310/E310-type) filler using low heat input, small stringer beads and interpass temperature control; fully austenitic ferrite-free weld metal is hot-crack sensitive and the high-carbon base is prone to HAZ carbide precipitation.

What surface finishes work on CK35MN-SA?

Grit blast plus pickle/passivate to remove casting scale; shot-peening or grinding improves fatigue, and aluminizing or diffusion coating extends life above 1000 °C in sulphur-bearing gas.

Can CK35MN-SA be formed, bent or molded?

A casting grade only — not intended for cold forming; design generous fillets, uniform sections and adequate risers, allow ~2 % solidification shrinkage and avoid hot-tear-prone sharp corners.

What is the maximum service temperature of CK35MN-SA?

CK35MN-SA is rated for continuous use to about 1,050°C (1,922 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between CK35MN-AC and CK35MN-SA?

AC is the default condition — standard supply condition for heat-resistant service — carbides in the as-cast network actually aid creep strength. SA: choose when maximum ductility, toughness and aqueous corrosion resistance are needed before service; dissolves the as-cast carbide network. Yield strength is 250 MPa in AC versus 230 MPa in SA.

Sources

  1. ASTM A351/A351M — Castings, Austenitic, for Pressure-Containing Parts — ASTM International (2018)
  2. ASTM A743/A743M — Castings, Iron-Chromium, Iron-Chromium-Nickel, Corrosion Resistant, for General Application — ASTM International (2019)
  3. High Alloy Data Sheets, Heat Series (CK-type / HK-type alloys) — Steel Founders' Society of America (2004)
  4. ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
  5. ASM Handbook Vol.13B — Corrosion: Materials — ASM International (2005)

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.