Stainless Steel 439
AISI/SAE 439 · UNS S43035 · EN 1.4510, X3CrTi17 · JIS SUS430LX, SUS439 · GB 022Cr17Ti, 022Cr18Ti
439 is a titanium-stabilized 17% Cr ferritic stainless (S43035, 1.4510, X3CrTi17, SUS430LX/SUS439) with low carbon, so it resists intergranular corrosion after welding without a post-weld anneal.
Values for the Annealed condition
439 tempers and conditions
439 is supplied in 2 conditions, soft to hard. Annealed is the default FabDigit quotes; the values on this page are for it.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault cold rolled, annealed and pickled (2B/2D sheet, standard supply) | Standard stocked condition for forming, welding and general fabrication of sheet, strip and tube. | 310 | 485 | 30 | 150 HB | 2.9 % IACS |
TR 1/4 Hard | Choose when extra stiffness, flatness and springback control are wanted for roll-formed or lightly bent parts. | 480 | 580 | 15 | 10 HRC | 2.9 % IACS |
Supply forms, finishes and certifications
Ways 439 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
Tube-Ann | Welded tube, bright annealed | Supply form |
BA | Bright annealed | Surface finish |
HRAP | Hot rolled, annealed and pickled | Surface finish |
What is 439?
439 is a titanium-stabilized 17% Cr ferritic stainless (S43035, 1.4510, X3CrTi17, SUS430LX/SUS439) with low carbon, so it resists intergranular corrosion after welding without a post-weld anneal. It is stocked as sheet, strip and tube in annealed, BA, HRAP, TR-1/4H and tube-annealed conditions, with 310 MPa yield, 485 MPa tensile, 30% elongation, 150 HB and service to 815 °C, and it deep-draws and roll-forms well (formability score 72). Chloride pitting resistance is lower than the Mo-bearing 434/436, and elongation and springback are less favourable than 304. Move to 436 where added pitting resistance is needed. 439 has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,425°C (2,597 °F). 439 has a yield strength of 310 MPa (45 ksi) and a tensile strength of 485 MPa (70.3 ksi) — weaker than 63% of stainless steel grades. Elongation at break is 30% and the elastic modulus is 200 GPa (29 Msi).
What is 439 used for?
- Automotive exhaust manifolds and tubing
- Solar absorber panels
- Appliance and water-heater tubing
- Heat exchanger tubes and shells
- Catering and kitchen equipment panels
- Roofing, gutters and cladding
- Welded ducting and flue components
Advantages
- Low embodied carbon — 3.4 kg CO₂/kg, better than 91% of stainless steel grades
- Easy to machine — 50/100, better than 90% of stainless steel grades
- High electrical conductivity — 2.9 % IACS, better than 87% of stainless steel grades
- Readily welded — 82/100, better than 84% of stainless steel grades
- Forms and bends easily — 72/100, better than 84% of stainless steel grades
Limitations
- Needs corrosion protection — 48/100, worse than 80% of stainless steel grades
- Low fracture toughness — 80 MPa·√m (72.8 ksi·√in), worse than 79% of stainless steel grades
439 properties
Typical room-temperature values for 439-Annealed; bars are the position among stainless steel grades.
Physical3
439 has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
439 has a yield strength of 310 MPa (45 ksi) and a tensile strength of 485 MPa (70.3 ksi) — weaker than 63% of stainless steel grades. Elongation at break is 30% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
439 is rated for continuous service to 815°C (1,499 °F). It conducts heat at 24 W/m·K (13.9 BTU/hr·ft·°F), better than 81% of stainless steel grades. Thermal expansion is 10.4 µm/m·K (5.78 µin/in·°F).
Electrical3
439 conducts electricity at 2.9 % IACS, better than 87% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (48/100), worse than 80% of stainless steel grades.
Sustainability4
Producing a kilogram of 439 takes about 50 MJ of energy and emits 3.4 kg of CO₂ — less than 80% of stainless steel grades. Typical recycled content is 65%.
Manufacturability7
439's machinability is fair (50/100, better than 90% of stainless steel grades); weldability very good (82/100); formability very good (72/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. 439 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 439
Is 439 easy to machine?
Machines like 430 — soft and slightly gummy; use sharp positive-rake carbide, rigid setups, moderate speed with heavy coolant to avoid built-up edge and work-hardened skin.
Can 439 be welded?
Very good with GTAW/GMAW/laser/resistance methods; Ti stabilization prevents sensitization so no post-weld anneal is normally needed, but keep heat input and interpass temperature low to limit grain coarsening and use 409/439 or 316L filler.
Can 439 be formed, bent or molded?
Good deep-drawing and roll-forming behaviour with low ridging/roping thanks to Ti stabilization; allow for lower elongation and higher springback than 304 and avoid sharp bends across the rolling direction in heavy gauge.
Manufacturability
The process limits FabDigit applies to 439. Every 439 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Better50 / 100 |
|---|---|
| ISO material group | M.1 |
| Cutting speed (rough / finish) | 150 / 180 m/min |
| Minimum wall | 0.8 mm |
| Minimum internal radius | 1.5 mm |
| Drill depth limit | 4× diameter |
| Best surface (machined / polished) | Ra 1.6 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Better72 / 100 |
|---|---|
| Weldability | Fair82 / 100 |
| Bendable | Yes |
439 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 |
|---|---|---|
| Cextra-low carbon for weld ductility | ≤ 0.03 | 0.02 |
| Si | ≤ 1 | 0.4 |
| Mn | ≤ 1 | 0.4 |
| P | ≤ 0.04 | 0.03 |
| S | ≤ 0.03 | 0 |
| Cr | 17 – 19 | 17.8 |
| Niresidual | ≤ 0.5 | 0.25 |
| Timin = 0.20 + 4(C+N) stabilization | 0.2 – 1.1 | 0.35 |
| N | ≤ 0.03 | 0.02 |
| Al | ≤ 0.15 | 0.05 |
| Fe | balance |
What surface finishes work on 439?
Pickle and passivate after hot work; takes bright-annealed, No.4 brushed and electropolished finishes well, and accepts painting or PVD coatings — do not anodize.
Surface treatments FabDigit runs on stainless steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Plating
Organic Coating
CVD Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel 439 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S43035
- EN / DIN / Werkstoff-Nr.
- 1.4510X3CrTi171.4520
- GB (China)
- 022Cr17Ti022Cr18Ti0Cr17Ti
- JIS
- SUS430LXSUS439
How much does 439 cost?
439 is a premium-cost stainless steel ($$$), cheaper than about 58% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
439 — frequently asked
What is 439 used for?
439 is typically used for automotive exhaust manifolds and tubing, solar absorber panels, appliance and water-heater tubing, heat exchanger tubes and shells, catering and kitchen equipment panels and roofing, gutters and cladding. In short: stabilized weldable ferritic stainless.
What is the yield strength of 439?
439 has a typical yield strength of 310 MPa (45 ksi) and a tensile strength of 485 MPa (70.3 ksi) — weaker than 63% of stainless steel grades. Strength varies by condition: see the 2 listed tempers.
Is 439 easy to machine?
Reasonably — machinability is rated fair (50/100, better than 90% of stainless steel grades). Machines like 430 — soft and slightly gummy; use sharp positive-rake carbide, rigid setups, moderate speed with heavy coolant to avoid built-up edge and work-hardened skin.
Can 439 be welded?
Yes — weldability is rated very good (82/100). Very good with GTAW/GMAW/laser/resistance methods; Ti stabilization prevents sensitization so no post-weld anneal is normally needed, but keep heat input and interpass temperature low to limit grain coarsening and use 409/439 or 316L filler.
What surface finishes work on 439?
Pickle and passivate after hot work; takes bright-annealed, No.4 brushed and electropolished finishes well, and accepts painting or PVD coatings — do not anodize.
Can 439 be formed, bent or molded?
Good deep-drawing and roll-forming behaviour with low ridging/roping thanks to Ti stabilization; allow for lower elongation and higher springback than 304 and avoid sharp bends across the rolling direction in heavy gauge.
What is the maximum service temperature of 439?
439 is rated for continuous use to about 815°C (1,499 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 439 cost?
439 is a premium-cost stainless steel ($$$), cheaper than about 58% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in 439?
Yes — 439 is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet and Strip (UNS S43035) — ASTM International (2023)
- ASTM A268/A268M — Seamless and Welded Ferritic Stainless Steel Tubing (TP439) — ASTM International (2022)
- EN 10088-2 — Stainless steels: technical delivery conditions for sheet/plate (1.4510 X3CrTi17) — CEN (2014)
- GB/T 3280 (022Cr18Ti) — SAC (2015)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- 439 / 1.4510 ferritic stainless steel product data — Outokumpu / Cleveland-Cliffs (AK Steel) (2021)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.