Stainless Steel S41425-T (Quenched and tempered)
Heat-treated state
UNS S41425
Lower-strength Q&T condition with maximum toughness and the widest sour-service envelope (hardness held ≤ 28 HRC).
Values for the T condition
Other S41425 tempers and conditions
S41425 is listed in 5 conditions; see the grade overview at S41425.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softened delivery condition for machining, forming or as an intermediate before final Q&T. | 570 | 760 | 24 | 22 HRC | — |
TThis page Quenched and tempered | Lower-strength Q&T condition with maximum toughness and the widest sour-service envelope (hardness held ≤ 28 HRC). | 690 | 850 | 19 | 25 HRC | 2.5 % IACS |
HTDefault Quenched and double tempered | Standard high-strength delivery condition for downhole tubulars, wellhead and valve parts requiring 95 ksi class yield with ≤ 32 HRC. | 810 | 930 | 17 | 29 HRC | 2.5 % IACS |
quenched and tempered to 110 ksi (758 MPa) minimum yield | Higher-strength oilfield tubular grade (super 13Cr 110) for deeper wells; sour-service window is narrower than the 95 ksi class. | 810 | 950 | 18 | 32 HRC | — |
quenched and tempered to 125 ksi (862 MPa) minimum yield | Maximum-strength condition offered for sweet high-pressure wells; not qualified for most sour environments because hardness exceeds typical MR0175 caps. | 900 | 1,030 | 16 | 35 HRC | — |
What is S41425-T?
S41425-T is S41425 heat treated to T — lower-strength Q&T condition with maximum toughness and the widest sour-service envelope (hardness held ≤ 28 HRC). S41425-T has a yield strength of 690 MPa (100 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 92% of stainless steel grades. Elongation at break is 19% and the elastic modulus is 200 GPa (29 Msi). S41425-T has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F). HT is the default condition FabDigit quotes; T is available on request or by drawing note.
Advantages
- Conducts heat well — 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades
- High strength — 690 MPa (100 ksi), better than 92% of stainless steel grades
- Low embodied carbon — 3.4 kg CO₂/kg, better than 91% of stainless steel grades
Limitations
- Needs corrosion protection — 45/100, worse than 85% of stainless steel grades
- Limited ductility — 19%, worse than 81% of stainless steel grades
S41425-T properties
Typical room-temperature values for S41425-T; 40 are specific to this condition. Other listed values are S41425 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
S41425-T has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
S41425-T has a yield strength of 690 MPa (100 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 92% of stainless steel grades. Elongation at break is 19% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
S41425-T is rated for continuous service to 480°C (896 °F). It conducts heat at 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades. Thermal expansion is 10.8 µm/m·K (6 µin/in·°F).
Electrical3
S41425-T conducts electricity at 2.5 % IACS, better than 75% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 85% of stainless steel grades.
Sustainability4
Producing a kilogram of S41425-T takes about 53 MJ of energy and emits 3.4 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 40%.
Manufacturability7
S41425-T's machinability is fair (42/100, better than 79% of stainless steel grades); weldability very good (70/100); formability fair (35/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with S41425-T
Is S41425 easy to machine?
Machine in the tempered condition with rigid setups, sharp carbide tooling, low speed / heavy feed and flood coolant; the gummy low-carbon martensite work-hardens and rubs if feeds are too light.
Can S41425 be welded?
Readily weldable (GTAW/GMAW) with low heat input and matching supermartensitic or superduplex/Ni-base filler; a post-weld temper at about 600–650 °C restores HAZ toughness and keeps hardness under NACE limits.
Can S41425 be formed, bent or molded?
Hot forge/ring-roll at roughly 1150–900 °C followed by full austenitise-quench-temper; cold forming is limited to mild bending due to the high yield strength.
What surface finishes work on S41425?
Passivate or electropolish per ASTM A967 after machining; the fine martensitic structure takes a good mechanical polish, and shot peening or nitriding can be added for wear surfaces.
S41425 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 |
|---|---|---|
| Cultra-low carbon for weldability and SSC resistance | ≤ 0.05 | 0.02 |
| Mn | 0.5 – 1 | 0.7 |
| Si | ≤ 0.5 | 0.25 |
| P | ≤ 0.02 | 0.01 |
| Slow S for sour service | ≤ 0.01 | 0 |
| Cr | 11.5 – 13.5 | 12.5 |
| Ni | 4 – 6 | 5 |
| Mo | 1.5 – 2.5 | 2 |
| Cu | ≤ 0.3 | 0.1 |
| Naustenite stabiliser / strengthener | 0.01 – 0.1 | 0.05 |
| Fe | balance | — |
S41425-T — frequently asked
What is S41425-T used for?
S41425-T is typically used for oil country tubular goods (OCTG), downhole tools, sour-service wellhead components and high-strength oilfield fasteners. In short: weldable high-strength 13Cr; sour-service martensitic grade; stronger than S41500.
What is the yield strength of S41425-T?
S41425-T has a typical yield strength of 690 MPa (100 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 92% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is S41425-T easy to machine?
Not especially — machinability is rated fair (42/100, better than 79% of stainless steel grades). Machine in the tempered condition with rigid setups, sharp carbide tooling, low speed / heavy feed and flood coolant; the gummy low-carbon martensite work-hardens and rubs if feeds are too light.
Can S41425-T be welded?
Yes — weldability is rated very good (70/100). Readily weldable (GTAW/GMAW) with low heat input and matching supermartensitic or superduplex/Ni-base filler; a post-weld temper at about 600–650 °C restores HAZ toughness and keeps hardness under NACE limits.
What surface finishes work on S41425-T?
Passivate or electropolish per ASTM A967 after machining; the fine martensitic structure takes a good mechanical polish, and shot peening or nitriding can be added for wear surfaces.
Can S41425-T be formed, bent or molded?
Hot forge/ring-roll at roughly 1150–900 °C followed by full austenitise-quench-temper; cold forming is limited to mild bending due to the high yield strength.
What is the maximum service temperature of S41425-T?
S41425-T is rated for continuous use to about 480°C (896 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between S41425-HT and S41425-A?
HT is the default condition — standard high-strength delivery condition for downhole tubulars, wellhead and valve parts requiring 95 ksi class yield with ≤ 32 HRC. A: softened delivery condition for machining, forming or as an intermediate before final Q&T. Yield strength is 810 MPa in HT versus 570 MPa in A.
Sources
- ASTM A479/A479M — Stainless Steel Bars and Shapes for Pressure Vessels — ASTM (2023)
- ASTM A276/A276M — Stainless Steel Bars and Shapes — ASTM (2017)
- ANSI/NACE MR0175 / ISO 15156-3 — Cracking-resistant CRAs for H2S-containing environments — NACE/ISO (2020)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Super 13Cr martensitic stainless OCTG datasheets (13Cr-5Ni-2Mo) — Nippon Steel / JFE / Vallourec (2021)
- GB/T 1220 / SY/T oilfield tubular material specifications — SAC / NEA China (2007)
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.