Steel 316LSi
AISI/SAE ER316LSi · ISO G 19 12 3 L Si
316LSi (ER316LSi) is a low-carbon austenitic stainless filler wire in which raised silicon improves arc stability and weld-pool wetting, making it a standard GMAW consumable and a common WAAM feedstock.
Reference datasheet — 316LSi 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 AW condition
316LSi tempers and conditions
316LSi is supplied in 4 conditions, soft to hard. AW is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed after deposition | Choose when maximum ductility, homogeneity and corrosion resistance are needed and residual stress must be removed from a WAAM part. | 250 | 520 | 55 | 150 HB | 2.4 % IACS |
Wire-arc additive, as-built deposit | Multi-layer arc-deposited block/wall; expect columnar grains and modest anisotropy between build and travel directions. | 330 | 545 | 45 | 170 HB | 2.3 % IACS |
Stress relieved | Low-temperature stress relief for dimensionally sensitive WAAM parts where full solution annealing (distortion) is unacceptable. | 350 | 560 | 45 | 165 HB | 2.3 % IACS |
AWDefault As-welded deposit | Standard condition for GMAW/GTAW joints made with ER316LSi; use for typical fabricated stainless weldments. | 400 | 580 | 40 | 175 HB | 2.3 % IACS |
Supply forms, finishes and certifications
Ways 316LSi is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
WIRE-CD | Cold drawn / bright layer-wound spooled wire | Supply form |
What is 316LSi?
316LSi (ER316LSi) is a low-carbon austenitic stainless filler wire in which raised silicon improves arc stability and weld-pool wetting, making it a standard GMAW consumable and a common WAAM feedstock. As-deposited it gives 400 MPa yield and 580 MPa tensile strength with 40 % elongation at 88 HRB, with a corrosion resistance score of 74 and service to about 450 °C. It is used where molybdenum-bearing 316L corrosion performance is needed in printed or welded structures rather than in wrought bar. Silicate islands must be cleaned between passes, and the deposit machines like any gummy austenitic stainless; wrought 316L is the alternative when a rolled product form is acceptable. 316LSi has a density of 7.98 g/cm³ (0.288 lb/in³), heavier than 94% of steel grades. It melts at 1,390°C (2,534 °F). 316LSi has a yield strength of 400 MPa (58 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 60% of steel grades. Elongation at break is 40% and the elastic modulus is 195 GPa (28.3 Msi).
What is 316LSi used for?
- WAAM stainless builds
- pipe welding
- tank fabrication
Advantages
- Good corrosion resistance — 74/100, better than 100% of steel grades
- Ductile — tolerates forming and impact — 40%, better than 99% of steel grades
- Tough — resists crack growth — 160 MPa·√m (145.6 ksi·√in), better than 98% of steel grades
- Readily welded — 92/100, better than 93% of steel grades
- Forms and bends easily — 78/100, better than 91% of steel grades
Limitations
- Poor heat conductor — 15 W/m·K (8.67 BTU/hr·ft·°F), worse than 98% of steel grades
- Low electrical conductivity — 2.3 % IACS, worse than 98% of steel grades
- High embodied carbon — 5.2 kg CO₂/kg, worse than 96% of steel grades
- Difficult to machine — 40/100, worse than 77% of steel grades
316LSi properties
Typical room-temperature values for 316LSi-AW; bars are the position among steel grades.
Physical3
316LSi has a density of 7.98 g/cm³ (0.288 lb/in³), heavier than 94% of steel grades. It melts at 1,390°C (2,534 °F).
Mechanical16
316LSi has a yield strength of 400 MPa (58 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 60% of steel grades. Elongation at break is 40% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal6
316LSi is rated for continuous service to 450°C (842 °F). It conducts heat at 15 W/m·K (8.67 BTU/hr·ft·°F), worse than 98% of steel grades. Thermal expansion is 16 µm/m·K (8.89 µin/in·°F).
Electrical3
316LSi conducts electricity at 2.3 % IACS, worse than 98% of steel grades.
Chemical & Environmental3
Corrosion resistance is very good (74/100), better than 100% of steel grades.
Sustainability4
Producing a kilogram of 316LSi takes about 56 MJ of energy and emits 5.2 kg of CO₂ — more than 95% of steel grades. Typical recycled content is 70%.
Manufacturability8
316LSi's machinability is fair (40/100, worse than 77% of steel grades); weldability excellent (92/100); 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 steel family
Yield strength against density for every steel grade FabDigit runs. 316LSi is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 316LSi
Is 316LSi easy to machine?
Gummy, work-hardening austenitic deposit — use sharp positive-rake carbide, rigid setups, high feed/low speed and flood coolant; WAAM porosity/silicate inclusions can chip edges.
Can 316LSi be welded?
Excellent GMAW/GTAW behaviour with Ar+2%CO₂ or Ar+2%O₂ (pure Ar for TIG); keep interpass below ~150 °C, control heat input, and remove silicate islands between passes in multi-pass welds.
Can 316LSi be formed, bent or molded?
As-deposited material is ductile and cold-formable, but heavy cold work raises strength quickly and induces strain-induced martensite; anneal at ~1050 °C for severe forming.
316LSi 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 for sensitisation resistance | ≤ 0.03 | 0.02 |
| Cr | 18 – 20 | 19 |
| Ni | 11 – 14 | 12.3 |
| Mo | 2 – 3 | 2.5 |
| Mn | 1 – 2.5 | 1.7 |
| Sithe 'Si' addition: improves wetting and arc stability | 0.65 – 1 | 0.85 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Cu | ≤ 0.75 | 0.2 |
| Nnot limited in all standards | ≤ 0.08 | 0.04 |
| Fe | balance |
What surface finishes work on 316LSi?
Grind/machine to remove build layer ridges, then pickle-passivate (ASTM A967) or electropolish; no anodising — high Si can leave slightly duller weld surfaces than 316L.
Surface treatments FabDigit runs on 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).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel 316LSi in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- AISI / SAE
- ER316LSi
- ISO
- G 19 12 3 L Si
How much does 316LSi cost?
316LSi is a premium-cost 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.
316LSi — frequently asked
What is 316LSi used for?
316LSi is typically used for WAAM stainless builds, pipe welding and tank fabrication. In short: best-wetting 316L wire; standard WAAM stainless feedstock; low-carbon, Mo-bearing deposit.
What is the yield strength of 316LSi?
316LSi has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 60% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is 316LSi easy to machine?
Not especially — machinability is rated fair (40/100, worse than 77% of steel grades). Gummy, work-hardening austenitic deposit — use sharp positive-rake carbide, rigid setups, high feed/low speed and flood coolant; WAAM porosity/silicate inclusions can chip edges.
Can 316LSi be welded?
Yes — weldability is rated excellent (92/100). Excellent GMAW/GTAW behaviour with Ar+2%CO₂ or Ar+2%O₂ (pure Ar for TIG); keep interpass below ~150 °C, control heat input, and remove silicate islands between passes in multi-pass welds.
What surface finishes work on 316LSi?
Grind/machine to remove build layer ridges, then pickle-passivate (ASTM A967) or electropolish; no anodising — high Si can leave slightly duller weld surfaces than 316L.
Can 316LSi be formed, bent or molded?
As-deposited material is ductile and cold-formable, but heavy cold work raises strength quickly and induces strain-induced martensite; anneal at ~1050 °C for severe forming.
What is the maximum service temperature of 316LSi?
316LSi is rated for continuous use to about 450°C (842 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 316LSi-AW and 316LSi-SA?
AW is the default condition — standard condition for GMAW/GTAW joints made with ER316LSi; use for typical fabricated stainless weldments. SA: choose when maximum ductility, homogeneity and corrosion resistance are needed and residual stress must be removed from a WAAM part. Yield strength is 400 MPa in AW versus 250 MPa in SA.
How much does 316LSi cost?
316LSi is a premium-cost 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
- AWS A5.9/A5.9M — Bare Stainless Steel Welding Electrodes and Rods (ER316LSi) — AWS (2017)
- EN ISO 14343 — Welding consumables, wire electrodes for arc welding of stainless steels (G 19 12 3 L Si) — ISO (2017)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- ER316LSi solid wire all-weld-metal datasheets (ESAB / Böhler / Lincoln Electric) — various (2023)
- Published WAAM 316L/316LSi mechanical property studies (as-built and solution-annealed) — peer-reviewed literature (2022)
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.