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Stainless Steel ZG40Cr25Ni12Si2-SA

Heat-treated state

ASTM HH

SA = solution annealed 1050–1150 °C, water quenched

Choose when maximum room-temperature ductility/impact toughness or machining before service is required; dissolves grain-boundary carbide network.

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Values for the SA condition

Other ZG40Cr25Ni12Si2 tempers and conditions

ZG40Cr25Ni12Si2 is listed in 4 conditions; see the grade overview at ZG40Cr25Ni12Si2.

Compare all 4 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
SAThis page
Solution annealed 1050–1150 °C, water quenched
Choose when maximum room-temperature ductility/impact toughness or machining before service is required; dissolves grain-boundary carbide network.28059026170 HB1.9 % IACS
FDefault
As fabricated
Standard supply condition for furnace hardware; HH is normally used as-cast because service temperature itself homogenizes the structure.31060018185 HB1.9 % IACS
Centrifugally cast tube/ring
Pick for radiant tubes, rolls and rings — columnar centrifugal structure gives sounder walls and somewhat higher strength than static sand casting.33064015195 HB1.9 % IACS
Aged / service-exposed
Reference condition for design of parts that have seen long exposure at 650–900 °C — strength stays high but room-temperature ductility collapses.380620419 HRC2 % IACS

What is ZG40Cr25Ni12Si2-SA?

ZG40Cr25Ni12Si2-SA is ZG40Cr25Ni12Si2 heat treated to SA — choose when maximum room-temperature ductility/impact toughness or machining before service is required; dissolves grain-boundary carbide network. ZG40Cr25Ni12Si2-SA has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 75% of stainless steel grades. Elongation at break is 26% and the elastic modulus is 185 GPa (26.8 Msi). ZG40Cr25Ni12Si2-SA has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,370°C (2,498 °F). F 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

  • Hard to polish — 45/100, worse than 96% of stainless steel grades
  • Limited formability — 14/100, worse than 92% of stainless steel grades
  • Low electrical conductivity — 1.9 % IACS, worse than 84% of stainless steel grades
  • Difficult to weld — 45/100, worse than 79% of stainless steel grades
  • Low strength — 280 MPa (40.6 ksi), worse than 75% of stainless steel grades

ZG40Cr25Ni12Si2-SA properties

Typical room-temperature values for ZG40Cr25Ni12Si2-SA; 22 are specific to this condition. Other listed values are ZG40Cr25Ni12Si2 reference data and may not represent this condition. Bars are the position among stainless steel grades.

Physical3

ZG40Cr25Ni12Si2-SA has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,370°C (2,498 °F).

Density7.7 g/cm³0.28 lb/in³
Melting Point (Solidus)1,370°C2,498 °F
Liquidus Temperature1,410°C2,570 °F

Mechanical15

ZG40Cr25Ni12Si2-SA has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 75% of stainless steel grades. Elongation at break is 26% and the elastic modulus is 185 GPa (26.8 Msi).

Elastic (Young's) Modulus185 GPa26.8 Msi
Shear Modulus72 GPa10.4 Msi
Bulk Modulus154 GPa22.3 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)590 MPa85.6 ksi
Yield Strength (0.2% offset)280 MPa40.6 ksi
Elongation at Break26%
Reduction in Area32%
Compressive Strength290 MPa42.1 ksi
Shear Strength390 MPa56.6 ksi
Fatigue Strength (Endurance Limit)220 MPa31.9 ksi
Charpy V-Notch Impact (RT)38 J28 ft·lbf
Hardness, Brinell170 HB
Hardness, Rockwell B86 HRB
Hardness, Vickers180 HV

Thermal6

ZG40Cr25Ni12Si2-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 16.5 µm/m·K (9.17 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)16.5 µm/m·K9.2 µin/in·°F
Latent Heat of Fusion265 J/g114 BTU/lb
Max Service Temperature (continuous)1,050°C1,922 °F
Min Service Temperature-30°C-22 °F

Electrical3

ZG40Cr25Ni12Si2-SA conducts electricity at 1.9 % IACS, worse than 84% of stainless steel grades.

Electrical Conductivity1.9 % IACS
Electrical Resistivity9×10⁻⁷ Ω·m35.4 µΩ·in
Magnetic Responseweakly magnetic

Chemical & Environmental3

Corrosion resistance is good (60/100), worse than 58% of stainless steel grades.

Galvanic Potential (seawater, vs SCE)-0.1 V
Corrosion ResistanceGood60/100
Chemical Resistance SummaryExcellent scaling resistance in oxidizing air/combustion gas to ~1050 °C; fair in low-sulfur reducing gas; poor in high-sulfur or strongly carburizing/nitriding atmospheres and in chloride-bearing aqueous media (pitting, SCC).

Sustainability4

Producing a kilogram of ZG40Cr25Ni12Si2-SA takes about 52 MJ of energy and emits 4.8 kg of CO₂ — less than 76% of stainless steel grades. Typical recycled content is 75%.

Embodied Energy (primary production)52 MJ/kg22,356 BTU/lb
Embodied Carbon (primary production)4.8 kg CO₂/kg
Embodied Water190 L/kg22.8 gal/lb
Typical Recycled Content75%

Manufacturability7

ZG40Cr25Ni12Si2-SA's machinability is poor (32/100, worse than 62% of stainless steel grades); weldability fair (45/100); formability not recommended (14/100).

MachinabilityPoor32/100
Machinability Rating (AISI 1212 = 100 %)34%
WeldabilityFair45/100
Formability (cold)Not recommended14/100
CastabilityVery good78/100
Brazeability / SolderabilityFair35/100
PolishabilityFair45/100

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

Working with ZG40Cr25Ni12Si2-SA

Is ZG40Cr25Ni12Si2 easy to machine?

Machine in the solution-annealed state where possible; use rigid setups, positive-rake carbide (C2/K20 or coated), low speed 15–30 m/min and heavy positive feed to cut under the work-hardened layer, with abundant coolant.

Can ZG40Cr25Ni12Si2 be welded?

Weldable by SMAW/GTAW/FCAW with 25Cr-12Ni (E309/ER309) or over-alloyed 25Cr-20Ni filler; preheat 150–250 °C for heavy or service-aged sections, keep interpass low, and re-solution-treat aged parts before repair welding to avoid σ-phase cracking.

Can ZG40Cr25Ni12Si2 be formed, bent or molded?

Cast only — sand, shell or investment casting with generous risers and chills; no cold forming, and hot straightening must be done above ~1000 °C followed by fast cooling.

What surface finishes work on ZG40Cr25Ni12Si2?

Shot blast and pickle/passivate to remove casting scale; not anodizable, and mechanical polishing is limited by coarse dendritic grains and carbides — a protective in-service Cr₂O₃/SiO₂ scale forms naturally on first heating.

ZG40Cr25Ni12Si2 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/carbide strengthening0.3 – 0.50.4
Siimproves scaling resistance1 – 2.51.8
Mn≤ 21
Pimpurity≤ 0.04—
Simpurity≤ 0.03—
Cr24 – 2725.5
Ni11 – 1412.5
Moresidual, restricted≤ 0.5—
Febalance—

ZG40Cr25Ni12Si2-SA — frequently asked

What is ZG40Cr25Ni12Si2-SA used for?

ZG40Cr25Ni12Si2-SA is typically used for furnace grates, heat-treatment fixtures, burner components and high-temperature process castings. In short: ASTM HH equivalent; lower-nickel heat-resistant casting; stronger than HK.

What is the yield strength of ZG40Cr25Ni12Si2-SA?

ZG40Cr25Ni12Si2-SA has a typical yield strength of 280 MPa (40.6 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 75% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.

Is ZG40Cr25Ni12Si2-SA easy to machine?

Not especially — machinability is rated poor (32/100, worse than 62% of stainless steel grades). Machine in the solution-annealed state where possible; use rigid setups, positive-rake carbide (C2/K20 or coated), low speed 15–30 m/min and heavy positive feed to cut under the work-hardened layer, with abundant coolant.

Can ZG40Cr25Ni12Si2-SA be welded?

With care — weldability is rated fair (45/100). Weldable by SMAW/GTAW/FCAW with 25Cr-12Ni (E309/ER309) or over-alloyed 25Cr-20Ni filler; preheat 150–250 °C for heavy or service-aged sections, keep interpass low, and re-solution-treat aged parts before repair welding to avoid σ-phase cracking.

What surface finishes work on ZG40Cr25Ni12Si2-SA?

Shot blast and pickle/passivate to remove casting scale; not anodizable, and mechanical polishing is limited by coarse dendritic grains and carbides — a protective in-service Cr₂O₃/SiO₂ scale forms naturally on first heating.

Can ZG40Cr25Ni12Si2-SA be formed, bent or molded?

Cast only — sand, shell or investment casting with generous risers and chills; no cold forming, and hot straightening must be done above ~1000 °C followed by fast cooling.

What is the maximum service temperature of ZG40Cr25Ni12Si2-SA?

ZG40Cr25Ni12Si2-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 ZG40Cr25Ni12Si2-F and ZG40Cr25Ni12Si2 Aged?

F is the default condition — standard supply condition for furnace hardware; HH is normally used as-cast because service temperature itself homogenizes the structure. Aged: reference condition for design of parts that have seen long exposure at 650–900 °C — strength stays high but room-temperature ductility collapses. Yield strength is 310 MPa in F versus 380 MPa in Aged.

Sources

  1. ASTM A297/A297M — Steel Castings, Iron-Chromium and Iron-Chromium-Nickel, Heat Resistant, for General Application (Grade HH) — ASTM International (2020)
  2. ASTM A608/A608M — Centrifugally Cast Iron-Chromium-Nickel High-Alloy Tubing for Pressure Application at High Temperatures — ASTM International (2018)
  3. ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (Heat-Resistant Castings) — ASM International (1990)
  4. Steel Castings Handbook, High Alloy Data Sheets — Heat Series — Steel Founders' Society of America (2004)

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.