01

Selection summary

Overview

316L combines the localized-corrosion benefit of molybdenum with a low carbon limit intended to reduce sensitization risk in welded assemblies. It is a common specification for process, pharmaceutical, food, coastal, and hygienic equipment, but it still requires environmental and surface-condition review.

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Engineering scope

This page separates standard-oriented limits from typical reference data. Purchase acceptance comes from the ordered specification and certified material test report.

02

Names and systems

Identity & standards

Common grade316L
UNS · canonicalS31603
EN · commonly-compared1.4404 (X2CrNiMo17-12-2)

Similar designations across ASTM, EN, JIS, and other systems are not automatically interchangeable. Product form and ordered standard control chemistry, properties, dimensions, condition, and testing.

03

Reference chemistry

Composition

ElementReference rangeWhy it matters
Carbon≤ 0.030%Reduced weld sensitization risk
Chromium16.0–18.0%Passive-film formation
Nickel10.0–14.0%Austenitic structure
Molybdenum2.0–3.0%Localized corrosion resistance

Concise grade-family reference only. Confirm every element limit against the current standard for the exact product ordered.

04

Condition matters

Reference properties

Yield strength≥ 170 MPa

Annealed flat product; ASTM-oriented summary

Tensile strength≥ 485 MPa

Annealed flat product; verify thickness and standard

Density≈ 8.0 g/cm³

Typical room-temperature reference

05

Environment first

Corrosion behavior

01

Improved pitting resistance compared with 304L in many chloride-bearing environments.

02

Not immune to seawater attack, chloride stress-corrosion cracking, or crevice corrosion.

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No material grade is universally corrosion-proof

Temperature, concentration, deposits, crevices, stress, surface finish, cleaning, and fabrication quality can change service performance.

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Service limits

Temperature & service

01

Review stress-corrosion cracking and code allowables for hot chloride service.

07

Delivery condition

Heat treatment & condition

01

316L is normally supplied solution annealed and rapidly cooled; low carbon limits sensitization risk but cannot repair heat tint, contamination, or an unsuitable weld procedure.

02

It is not thermally hardenable. Strength can rise through cold work, so annealed and cold-worked property sets must not be mixed.

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Process route

Fabrication

01

Well suited to welded fabrication; filler, purge, heat input, and cleaning remain procedure-controlled.

02

Excellent formability; machining must manage rapid work hardening.

Magnetic response: Normally low magnetic response when annealed; fabrication can create local response.

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Decision boundaries

Comparisons & substitution

01

316L commonly provides better chloride pitting resistance than 304L, yet warm stagnant seawater or crevice conditions may require a duplex or more highly alloyed grade.

02

Use 316 rather than 316L only when the ordered specification, fabrication route, and temperature design justify the higher-carbon grade.

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Where it is used

Applications

Pharmaceutical systemsChemical tanks and pipingCoastal fixturesFood-processing equipment
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Ordering scope

Product forms & standards

01

Plate, sheet, and strip under the applicable flat-product specification and ordered finish.

02

Bar, rod, shapes, and forgings under the product-specific stainless standard.

03

Seamless or welded pipe and tube under the ordered dimensional, service, and testing specification.

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Decision support

Selection guidance

Choose this grade when

  • A welded assembly needs more chloride resistance than 304L.
  • Cleanability, formability, and broad process-industry acceptance matter.

Review another grade when

  • Duplex strength can reduce section size.
  • The environment contains hot concentrated chlorides or stagnant seawater.
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Before ordering

Procurement checklist

01Order control

Name the governing product standard, edition, dimensions, tolerances, edge, finish, and delivery condition.

02Order control

Require the exact UNS designation and a material test report; a familiar trade name alone is not an acceptance criterion.

03Order control

Confirm corrosion environment, design temperature, fabrication route, inspection, certification, marking, and packaging before order release.

Ask for sourcing assistance from China
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Traceable evidence

Sources & review