Stainless Steel 317LM
AISI/SAE 317LM · UNS S31725
317LM (UNS S31725) is a low-carbon austenitic stainless steel in the 3xx family, a higher-molybdenum variant of 317L that uses the extra Mo to improve pitting and crevice corrosion resistance in chloride-bearing media.
Reference datasheet — 317LM is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the Annealed condition
317LM tempers and conditions
317LM is supplied in 5 conditions, soft to hard. Annealed is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault solution annealed (~1040–1120 °C, water quenched) plate/sheet | Standard stock condition for all corrosion service — maximum corrosion resistance, ductility and weldability. | 290 | 600 | 50 | 165 HB | — |
weld metal / HAZ, no post-weld heat treatment | Typical fabricated condition; low carbon avoids sensitisation, but use over-alloyed filler (ER317L or Ni-base 625) to offset Mo segregation. | 350 | 600 | 35 | 180 HB | 2.2 % IACS |
Cold Drawn / cold finished bar (annealed then lightly drawn) | Bar stock for shafts, fasteners and machined fittings needing better tolerance and higher yield than annealed. | 460 | 700 | 30 | 210 HB | — |
Quarter hard | Choose when structural strength must roughly double with only moderate loss of formability. | 600 | 900 | 20 | 25 HRC | — |
Half hard | Highest commonly stocked cold-worked strength level for springs, clamps and strapping; forming is limited to gentle bends. | 800 | 1,070 | 14 | 32 HRC | 2.2 % IACS |
Supply forms, finishes and certifications
Ways 317LM is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
Annealed-CR-Sheet | Cold Rolled, Annealed sheet | Supply form |
Annealed-HR-Plate | Hot Rolled, Annealed & Pickled plate | Supply form |
Annealed-Tube | Annealed seamless / welded tube & pipe | Supply form |
What is 317LM?
317LM (UNS S31725) is a low-carbon austenitic stainless steel in the 3xx family, a higher-molybdenum variant of 317L that uses the extra Mo to improve pitting and crevice corrosion resistance in chloride-bearing media. It is supplied as annealed hot-rolled plate, cold-rolled sheet, tube and cold-drawn bar; annealed material gives 290 MPa yield, 600 MPa tensile, 50 % elongation and 165 HB (82 HRB), with service to 800 °C. It welds without pre- or post-weld heat treatment but machines slowly because the austenite is gummy and work-hardens, and it costs more than 316L. Where chlorides are more aggressive, step up to 317LMN or a 6 % Mo superaustenitic. 317LM has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,375°C (2,507 °F). 317LM has a yield strength of 290 MPa (42.1 ksi) and a tensile strength of 600 MPa (87 ksi) — weaker than 72% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 200 GPa (29 Msi).
What is 317LM used for?
- pulp bleach plants
- seawater equipment
- chemical process piping
Advantages
- Ductile — tolerates forming and impact — 50%, better than 90% of stainless steel grades
- Forms and bends easily — 78/100, better than 90% of stainless steel grades
- Polishes to a fine finish — 80/100, better than 89% of stainless steel grades
- Readily welded — 85/100, better than 87% of stainless steel grades
- Tough — resists crack growth — 200 MPa·√m (182 ksi·√in), better than 86% of stainless steel grades
317LM properties
Typical room-temperature values for 317LM-Annealed; bars are the position among stainless steel grades.
Physical3
317LM has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,375°C (2,507 °F).
Mechanical15
317LM has a yield strength of 290 MPa (42.1 ksi) and a tensile strength of 600 MPa (87 ksi) — weaker than 72% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
317LM is rated for continuous service to 800°C (1,472 °F). It conducts heat at 14.2 W/m·K (8.2 BTU/hr·ft·°F), worse than 76% of stainless steel grades. Thermal expansion is 16.5 µm/m·K (9.17 µin/in·°F).
Electrical3
317LM conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (78/100), better than 84% of stainless steel grades.
Sustainability4
Producing a kilogram of 317LM takes about 58 MJ of energy and emits 5.2 kg of CO₂ — more than 66% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
317LM's machinability is fair (38/100, better than 63% of stainless steel grades); weldability excellent (85/100); formability very good (78/100).
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. 317LM is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 317LM
Is 317LM easy to machine?
Gummy and strongly work-hardening — use rigid setups, positive-rake sharp carbide, heavy constant feed, 20–35 % lower surface speed than 304, and flood high-lubricity coolant.
Can 317LM be welded?
Readily welded by GTAW/GMAW/SMAW with no pre- or post-weld heat treatment; use ER/E317L or over-alloyed Ni-base (625/C-276) filler for full weld-metal corrosion resistance and keep interpass temperature below ~150 °C.
Can 317LM be formed, bent or molded?
Cold forms well but needs ~20–30 % more force and greater springback allowance than 304; hot work at 1150–1200 °C followed by solution anneal and water quench.
317LM 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 |
|---|---|---|
| Clow-carbon, sensitisation resistant | ≤ 0.03 | 0.02 |
| Mn | ≤ 2 | 1.5 |
| Si | ≤ 0.75 | 0.5 |
| P | ≤ 0.05 | 0.03 |
| S | ≤ 0.03 | 0 |
| Cr | 18 – 20 | 19 |
| Ni | 13.5 – 17.5 | 15 |
| Mo | 4 – 5 | 4.5 |
| N | ≤ 0.1 | 0.05 |
| Fe | balance |
What surface finishes work on 317LM?
Pickle and passivate (nitric or nitric–HF) after hot work or welding to restore the passive film; polishes to a bright mirror finish, no anodising applicable.
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).
Passivation
Organic Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel 317LM in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S31725
How much does 317LM cost?
317LM is a premium-cost stainless steel ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
317LM — frequently asked
What is 317LM used for?
317LM is typically used for pulp bleach plants, seawater equipment and chemical process piping. In short: higher-Mo 317L upgrade; chloride pitting resistance; weldable without PWHT.
What is the yield strength of 317LM?
317LM has a typical yield strength of 290 MPa (42.1 ksi) and a tensile strength of 600 MPa (87 ksi) — weaker than 72% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is 317LM easy to machine?
Not especially — machinability is rated fair (38/100, better than 63% of stainless steel grades). Gummy and strongly work-hardening — use rigid setups, positive-rake sharp carbide, heavy constant feed, 20–35 % lower surface speed than 304, and flood high-lubricity coolant.
Can 317LM be welded?
Yes — weldability is rated excellent (85/100). Readily welded by GTAW/GMAW/SMAW with no pre- or post-weld heat treatment; use ER/E317L or over-alloyed Ni-base (625/C-276) filler for full weld-metal corrosion resistance and keep interpass temperature below ~150 °C.
What surface finishes work on 317LM?
Pickle and passivate (nitric or nitric–HF) after hot work or welding to restore the passive film; polishes to a bright mirror finish, no anodising applicable.
Can 317LM be formed, bent or molded?
Cold forms well but needs ~20–30 % more force and greater springback allowance than 304; hot work at 1150–1200 °C followed by solution anneal and water quench.
What is the maximum service temperature of 317LM?
317LM is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 317LM cost?
317LM is a premium-cost stainless steel ($$$), cheaper than about 51% 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.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip — ASTM International (2023)
- ASTM A312/A312M — Seamless, Welded and Heavily Cold Worked Austenitic Stainless Steel Pipes — ASTM International (2022)
- ASTM A276/A479 — Stainless Steel Bars and Shapes — ASTM International (2022)
- ASTM A666 — Annealed or Cold-Worked Austenitic Stainless Steel Sheet, Strip, Plate and Flat Bar — ASTM International (2015)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.13B: Corrosion — Materials — ASM International (2005)
- 317L / 317LM / 317LMN austenitic stainless datasheets — Outokumpu / Sandvik / North American Stainless (2022)
- GB/T 24511 / GB/T 4237 (00Cr19Ni13Mo4 ) (2017)
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.