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Stainless Steel S40975-TR (Temper Rolled)

Supply condition

UNS S40975

Slight cold work for improved flatness, stiffness and stretcher-strain suppression in roll-formed shells.

Standard cost $$

Values for the TR condition

Other S40975 tempers and conditions

S40975 is listed in 2 conditions; see the grade overview at S40975.

Compare all 2 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
ANNDefault
Annealed
Standard stocked condition for converter shells, exhaust tubing and stampings — maximum formability and weldability.25044030145 HB—
TRThis page
Temper Rolled
Slight cold work for improved flatness, stiffness and stretcher-strain suppression in roll-formed shells.35049022178 HB2.9 % IACS

What is S40975-TR?

S40975-TR is S40975 supplied in the TR condition — slight cold work for improved flatness, stiffness and stretcher-strain suppression in roll-formed shells. S40975-TR has a yield strength of 350 MPa (50.8 ksi) and a tensile strength of 490 MPa (71.1 ksi) — weaker than 52% of stainless steel grades. Elongation at break is 22% and the elastic modulus is 200 GPa (29 Msi). S40975-TR has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,450°C (2,642 °F). ANN is the default condition FabDigit quotes; TR is available on request or by drawing note.

Advantages

  • Easy to machine — 58/100, better than 97% of stainless steel grades
  • Low embodied carbon — 3.4 kg CO₂/kg, better than 91% of stainless steel grades
  • Conducts heat well — 24.9 W/m·K (14.4 BTU/hr·ft·°F), better than 87% of stainless steel grades
  • High electrical conductivity — 2.9 % IACS, better than 87% of stainless steel grades

Limitations

  • Needs corrosion protection — 42/100, worse than 90% of stainless steel grades
  • Hard to polish — 55/100, worse than 89% of stainless steel grades
  • Limited ductility — 22%, worse than 75% of stainless steel grades

S40975-TR properties

Typical room-temperature values for S40975-TR; 21 are specific to this condition. Other listed values are S40975 reference data and may not represent this condition. Bars are the position among stainless steel grades.

Physical3

S40975-TR has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,450°C (2,642 °F).

Density7.7 g/cm³0.28 lb/in³
Melting Point (Solidus)1,450°C2,642 °F
Liquidus Temperature1,510°C2,750 °F

Mechanical15

S40975-TR has a yield strength of 350 MPa (50.8 ksi) and a tensile strength of 490 MPa (71.1 ksi) — weaker than 52% of stainless steel grades. Elongation at break is 22% and the elastic modulus is 200 GPa (29 Msi).

Elastic (Young's) Modulus200 GPa29 Msi
Shear Modulus77 GPa11.2 Msi
Bulk Modulus160 GPa23.2 Msi
Poisson's Ratio0.28
Tensile Strength (Ultimate)490 MPa71.1 ksi
Yield Strength (0.2% offset)350 MPa50.8 ksi
Elongation at Break22%
Reduction in Area55%
Compressive Strength355 MPa51.5 ksi
Shear Strength320 MPa46.4 ksi
Fatigue Strength (Endurance Limit)250 MPa36.3 ksi
Charpy V-Notch Impact (RT)30 J22.1 ft·lbf
Hardness, Brinell178 HB
Hardness, Rockwell B88 HRB
Hardness, Vickers188 HV

Thermal6

S40975-TR is rated for continuous service to 675°C (1,247 °F). It conducts heat at 24.9 W/m·K (14.4 BTU/hr·ft·°F), better than 87% of stainless steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).

Thermal Conductivity24.9 W/m·K14.4 BTU/hr·ft·°F
Specific Heat Capacity460 J/kg·K0.11 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)11.7 µm/m·K6.5 µin/in·°F
Latent Heat of Fusion260 J/g112 BTU/lb
Max Service Temperature (continuous)675°C1,247 °F
Min Service Temperature-20°C-4 °F

Electrical3

S40975-TR conducts electricity at 2.9 % IACS, better than 87% of stainless steel grades.

Electrical Conductivity2.9 % IACS
Electrical Resistivity6×10⁻⁷ Ω·m23.6 µΩ·in
Magnetic Responseferromagnetic

Chemical & Environmental3

Corrosion resistance is fair (42/100), worse than 90% of stainless steel grades.

Galvanic Potential (seawater, vs SCE)-0.3 V
Corrosion ResistanceFair42/100
Chemical Resistance SummaryGood resistance to hot exhaust gas, oxidation and mild atmospheric exposure; free-rusting surface stain in humid/salted environments; poor in chlorides, seawater and reducing acids; suitable for condensate in exhaust systems but not for pitting-critical duty.

Sustainability4

Producing a kilogram of S40975-TR takes about 42 MJ of energy and emits 3.4 kg of CO₂ — less than 95% of stainless steel grades. Typical recycled content is 70%.

Embodied Energy (primary production)42 MJ/kg18,057 BTU/lb
Embodied Carbon (primary production)3.4 kg CO₂/kg
Embodied Water110 L/kg13.2 gal/lb
Typical Recycled Content70%

Manufacturability6

S40975-TR's machinability is good (58/100, better than 97% of stainless steel grades); weldability very good (76/100); formability good (65/100).

MachinabilityGood58/100
Machinability Rating (AISI 1212 = 100 %)68%
WeldabilityVery good76/100
Formability (cold)Good65/100
Brazeability / SolderabilityGood65/100
PolishabilityGood55/100

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

Working with S40975-TR

Is S40975 easy to machine?

Machines like a soft low-alloy steel but is somewhat gummy — use sharp, positive-rake carbide, rigid setups, 0.1–0.3 mm/rev feeds and flood coolant to avoid built-up edge.

Can S40975 be welded?

Readily GTAW/GMAW/resistance/laser welded without post-weld anneal thanks to Ti stabilization; keep heat input low to limit HAZ grain growth, use 409Cb/430Ti or 308L/309L filler, and back-purge to avoid oxidation.

Can S40975 be formed, bent or molded?

Excellent roll-forming, deep-drawing and tube-bending behaviour with r-value typical of stabilized ferritics; watch springback and roping/ridging on heavily drawn panels.

What surface finishes work on S40975?

Normally used as-pickled or aluminized/painted; can be bead-blasted or brushed, but it stains in salt exposure — passivation or coating is recommended for cosmetic outer parts.

S40975 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
Clow-carbon stabilized ferritic≤ 0.030.02
Mn≤ 10.4
Siaids high-temperature oxidation resistance≤ 10.5
P≤ 0.040.03
S≤ 0.020
Cr10.5 – 11.7511.2
Nideliberate Ni addition for toughness / HAZ ductility (distinguishes S40975 from S40910/S40920)0.5 – 10.75
TiTi ≥ 6×(C+N) for stabilization0.1 – 10.25
N≤ 0.030.02
Febalance—

S40975-TR — frequently asked

What is S40975-TR used for?

S40975-TR is typically used for catalytic converter shells, exhaust heat shields, welded exhaust tube and pipe, muffler shells, exhaust flanges and brackets and deep-drawn exhaust end caps. In short: most formable 409 variant; converter-shell workhorse; good weldability, no PWHT.

What is the yield strength of S40975-TR?

S40975-TR has a typical yield strength of 350 MPa (50.8 ksi) and a tensile strength of 490 MPa (71.1 ksi) — weaker than 52% of stainless steel grades. Strength varies by condition: see the 2 listed tempers.

Is S40975-TR easy to machine?

Reasonably — machinability is rated good (58/100, better than 97% of stainless steel grades). Machines like a soft low-alloy steel but is somewhat gummy — use sharp, positive-rake carbide, rigid setups, 0.1–0.3 mm/rev feeds and flood coolant to avoid built-up edge.

Can S40975-TR be welded?

Yes — weldability is rated very good (76/100). Readily GTAW/GMAW/resistance/laser welded without post-weld anneal thanks to Ti stabilization; keep heat input low to limit HAZ grain growth, use 409Cb/430Ti or 308L/309L filler, and back-purge to avoid oxidation.

What surface finishes work on S40975-TR?

Normally used as-pickled or aluminized/painted; can be bead-blasted or brushed, but it stains in salt exposure — passivation or coating is recommended for cosmetic outer parts.

Can S40975-TR be formed, bent or molded?

Excellent roll-forming, deep-drawing and tube-bending behaviour with r-value typical of stabilized ferritics; watch springback and roping/ridging on heavily drawn panels.

What is the maximum service temperature of S40975-TR?

S40975-TR is rated for continuous use to about 675°C (1,247 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between S40975-ANN and S40975-TR?

ANN is the default condition — standard stocked condition for converter shells, exhaust tubing and stampings — maximum formability and weldability. TR: slight cold work for improved flatness, stiffness and stretcher-strain suppression in roll-formed shells. Yield strength is 250 MPa in ANN versus 350 MPa in TR.

Sources

  1. ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip — ASTM International (2023)
  2. ASTM A268/A268M — Seamless and Welded Ferritic and Martensitic Stainless Steel Tubing — ASTM International (2022)
  3. ASTM A1010 / SAE J405 UNS designations for stainless steels — ASTM / SAE (2020)
  4. ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
  5. Type 409 / 409 Ni ferritic stainless steel product data — AK Steel / Cleveland-Cliffs (2020)
  6. Stainless steel grade datasheets (ferritic 4xx series) — Outokumpu / worldstainless (2022)

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.