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Nickel Alloy Incoloy 925 CW+A-140

Supply condition

UNS N09925

CW+A-140 = cW+A 140 ksi

Highest strength level, used for high-load fasteners, springs and thin-wall pressure parts; hardness approaches sour-service limits so verify against ISO 15156 envelope.

High cost $$$$

Values for the CW+A-140 condition

Other Incoloy 925 tempers and conditions

Incoloy 925 is listed in 4 conditions; see the grade overview at Incoloy 925.

Compare all 4 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Solution annealed (≈1010 °C, rapid cool), non-aged
Softest condition — pick for cold forming, deep drawing, welding of tube/sheet, or as stock to be aged after machining.38076045185 HB—
STA 110 ksi
Lower-strength aged grade for sour-service parts where maximum toughness and lowest hardness (≤32 HRC) are wanted.8201,0703030 HRC—
STA-120Default
STA 120 ksi
The standard stocked condition for downhole tools, packers, hangers and fasteners in H₂S service (≤38 HRC per ISO 15156).8901,1702633 HRC—
CW+A-140This page
CW+A 140 ksi
Highest strength level, used for high-load fasteners, springs and thin-wall pressure parts; hardness approaches sour-service limits so verify against ISO 15156 envelope.1,0301,2752038 HRC—

What is Incoloy 925 CW+A-140?

Incoloy 925 CW+A-140 is Incoloy 925 supplied in the CW+A-140 condition — highest strength level, used for high-load fasteners, springs and thin-wall pressure parts; hardness approaches sour-service limits so verify against ISO 15156 envelope. Incoloy 925 CW+A-140 has a yield strength of 1,030 MPa (149 ksi) and a tensile strength of 1,275 MPa (185 ksi) — stronger than 96% of nickel alloy grades. Elongation at break is 20% and the elastic modulus is 200 GPa (29 Msi). Incoloy 925 CW+A-140 has a density of 8.08 g/cm³ (0.292 lb/in³), lighter than 81% of nickel alloy grades. It melts at 1,311°C (2,392 °F). STA-120 is the default condition FabDigit quotes; CW+A-140 is available on request or by drawing note.

Advantages

  • High strength — 1,030 MPa (149 ksi), better than 96% of nickel alloy grades
  • Tough — resists crack growth — 120 MPa·√m (109.2 ksi·√in), better than 75% of nickel alloy grades

Limitations

  • Limited ductility — 20%, worse than 76% of nickel alloy grades
  • Limited service temperature — 540°C (1,004 °F), worse than 75% of nickel alloy grades
  • Limited formability — 20/100, worse than 75% of nickel alloy grades

Incoloy 925 CW+A-140 properties

Typical room-temperature values for Incoloy 925 CW+A-140; 13 are specific to this condition. Other listed values are Incoloy 925 reference data and may not represent this condition. Bars are the position among nickel alloy grades.

Physical3

Incoloy 925 CW+A-140 has a density of 8.08 g/cm³ (0.292 lb/in³), lighter than 81% of nickel alloy grades. It melts at 1,311°C (2,392 °F).

Density8.08 g/cm³0.29 lb/in³
Melting Point (Solidus)1,311°C2,392 °F
Liquidus Temperature1,366°C2,491 °F

Mechanical15

Incoloy 925 CW+A-140 has a yield strength of 1,030 MPa (149 ksi) and a tensile strength of 1,275 MPa (185 ksi) — stronger than 96% of nickel alloy grades. Elongation at break is 20% and the elastic modulus is 200 GPa (29 Msi).

Elastic (Young's) Modulus200 GPa29 Msi
Shear Modulus77 GPa11.2 Msi
Bulk Modulus182 GPa26.4 Msi
Poisson's Ratio0.32
Tensile Strength (Ultimate)1,275 MPa185 ksi
Yield Strength (0.2% offset)1,030 MPa149 ksi
Elongation at Break20%
Reduction in Area40%
Shear Strength700 MPa102 ksi
Fatigue Strength (Endurance Limit)520 MPa75.4 ksi
Fracture Toughness (K_IC)120 MPa·√m109 ksi·√in
Charpy V-Notch Impact (RT)55 J40.6 ft·lbf
Hardness, Brinell355 HB
Hardness, Rockwell C38 HRC
Hardness, Vickers375 HV

Thermal6

Incoloy 925 CW+A-140 is rated for continuous service to 540°C (1,004 °F). It conducts heat at 11.4 W/m·K (6.59 BTU/hr·ft·°F), better than 53% of nickel alloy grades. Thermal expansion is 12.9 µm/m·K (7.17 µin/in·°F).

Thermal Conductivity11.4 W/m·K6.6 BTU/hr·ft·°F
Specific Heat Capacity435 J/kg·K0.1 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)12.9 µm/m·K7.2 µin/in·°F
Latent Heat of Fusion290 J/g125 BTU/lb
Max Service Temperature (continuous)540°C1,004 °F
Min Service Temperature-196°C-321 °F

Electrical3

Incoloy 925 CW+A-140 conducts electricity at 1.5 % IACS, better than 59% of nickel alloy grades.

Electrical Conductivity1.5 % IACS
Electrical Resistivity1.16×10⁻⁶ Ω·m45.7 µΩ·in
Magnetic Responsenon-magnetic (austenitic; relative permeability ≈1.002–1.01 in solution-annealed and aged states)

Chemical & Environmental3

Corrosion resistance is very good (82/100), better than 67% of nickel alloy grades.

Galvanic Potential (seawater, vs SCE)-0.1 V
Corrosion ResistanceVery good82/100
Chemical Resistance SummaryExcellent in sour (H₂S/CO₂/Cl⁻) oilfield brines, sulfuric and phosphoric acid, and against chloride SCC; Mo+Cr give good pitting/crevice resistance (PREN ≈ 30–33) but below alloy 625/718 in hot concentrated oxidizing acids and strong HF.

Sustainability4

Producing a kilogram of Incoloy 925 CW+A-140 takes about 160 MJ of energy and emits 12 kg of CO₂ — less than 53% of nickel alloy grades. Typical recycled content is 30%.

Embodied Energy (primary production)160 MJ/kg68,788 BTU/lb
Embodied Carbon (primary production)12 kg CO₂/kg
Embodied Water400 L/kg47.9 gal/lb
Typical Recycled Content30%

Manufacturability8

Incoloy 925 CW+A-140's machinability is poor (17/100, worse than 69% of nickel alloy grades); weldability fair (45/100); formability poor (20/100).

MachinabilityPoor17/100
Machinability Rating (AISI 1212 = 100 %)10%
WeldabilityFair45/100
Formability (cold)Poor20/100
CastabilityPoor25/100
Brazeability / SolderabilityFair45/100
PolishabilityVery good75/100
Anodizing Responsen/a — nickel alloy, not anodized; electropolishing or passivation used instead

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

Working with Incoloy 925 CW+A-140

Is Incoloy 925 easy to machine?

Machine in the solution-annealed state where possible; aged material needs rigid setups, positive-rake carbide or ceramic tooling, low speed (15–25 m/min carbide), heavy feed to cut under the work-hardened layer and flood coolant.

Can Incoloy 925 be welded?

GTAW/GMAW with alloy 625, 725 or matching 925 filler, low heat input and no preheat; re-solution + age after welding to restore full strength, and avoid welding in the aged condition for critical parts.

Can Incoloy 925 be formed, bent or molded?

Cold form only in the annealed condition (high work-hardening rate, ~2× the force of 304); hot work 1040–1180 °C with finishing above ~950 °C, then solution anneal and age.

What surface finishes work on Incoloy 925?

Not anodizable — use pickling/passivation, electropolish or mechanical polish; the Cr-rich passive film gives good as-machined corrosion behaviour, and shot peening is common on threaded downhole parts.

Incoloy 925 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
NiNi+Co basis in some specs42 – 4644
Cr19.5 – 22.521
Mo2.5 – 3.53
Cu1.5 – 32
Tiγ′ former1.9 – 2.42.1
Al0.1 – 0.50.3
Nboptional/residual in some specs≤ 0.5—
Mn≤ 10.4
Si≤ 0.50.2
C≤ 0.030.01
S≤ 0.030
P≤ 0.030.01
Feremainder, 22 % min≥ 22 (balance)—

Incoloy 925 CW+A-140 — frequently asked

What is Incoloy 925 CW+A-140 used for?

Incoloy 925 CW+A-140 is typically used for oilfield fasteners, downhole tools, subsea components and pump/valve shafts. In short: age-hardenable Alloy 825; sour-service high-strength grade; stronger than 825, harder to machine.

What is the yield strength of Incoloy 925 CW+A-140?

Incoloy 925 CW+A-140 has a typical yield strength of 1,030 MPa (149 ksi) and a tensile strength of 1,275 MPa (185 ksi) — stronger than 96% of nickel alloy grades. Strength varies by condition: see the 4 listed tempers.

Is Incoloy 925 CW+A-140 easy to machine?

Not especially — machinability is rated poor (17/100, worse than 69% of nickel alloy grades). Machine in the solution-annealed state where possible; aged material needs rigid setups, positive-rake carbide or ceramic tooling, low speed (15–25 m/min carbide), heavy feed to cut under the work-hardened layer and flood coolant.

Can Incoloy 925 CW+A-140 be welded?

With care — weldability is rated fair (45/100). GTAW/GMAW with alloy 625, 725 or matching 925 filler, low heat input and no preheat; re-solution + age after welding to restore full strength, and avoid welding in the aged condition for critical parts.

What surface finishes work on Incoloy 925 CW+A-140?

Not anodizable — use pickling/passivation, electropolish or mechanical polish; the Cr-rich passive film gives good as-machined corrosion behaviour, and shot peening is common on threaded downhole parts.

Can Incoloy 925 CW+A-140 be formed, bent or molded?

Cold form only in the annealed condition (high work-hardening rate, ~2× the force of 304); hot work 1040–1180 °C with finishing above ~950 °C, then solution anneal and age.

What is the maximum service temperature of Incoloy 925 CW+A-140?

Incoloy 925 CW+A-140 is rated for continuous use to about 540°C (1,004 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between Incoloy 925 STA-120 and Incoloy 925-SA?

STA-120 is the default condition — the standard stocked condition for downhole tools, packers, hangers and fasteners in H₂S service (≤38 HRC per ISO 15156). SA: softest condition — pick for cold forming, deep drawing, welding of tube/sheet, or as stock to be aged after machining. Yield strength is 890 MPa in STA-120 versus 380 MPa in SA.

Sources

  1. INCOLOY alloy 925 technical bulletin — Special Metals Corporation (2004)
  2. ASTM B805 — Precipitation-hardening nickel alloy (UNS N09925) bar, forgings and forging stock for sour service — ASTM International (2018)
  3. ANSI/NACE MR0175/ISO 15156-3 — Cracking-resistant CRAs for H₂S-containing environments — NACE/ISO (2020)
  4. API 6ACRA — Age-hardened nickel-based alloys for oil and gas drilling and production equipment — API (2015)
  5. ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)

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.