ASTM A276 / A276M: Standard Specification for Stainless Steel Bars and Shapes
ASTM A276 / A276M covers hot- and cold-finished stainless steel bars and shapes: rounds, squares, hexagons, plus hot-rolled or extruded angles, tees and channels. It's the ASTM International standard specification that lays out grades, conditions and mechanical requirements for general-purpose stainless bar. Crestflo machines instrumentation valve bodies, fitting bodies, manifold bodies and bar-stock thermowells from A276-family bar. Every part ships with an EN 10204 3.1 material test certificate and a heat number, and delivery runs 6–8 weeks.
Scope note: ASTM A276 covers stainless bars and shapes used as machining stock, not tube or pipe (ASTM A269 / A213 / A312), not forgings (ASTM A182), and not reinforcing bar or plate. It's the general-purpose bar spec. The pressure-vessel-qualified counterpart is ASTM A479. This page defines the standard itself, nothing more. Crestflo doesn't sell raw bar or mill product; it supplies finished instrumentation components machined from A276-conforming bar.
Request an ASTM A276 quote → · Reach Crestflo at sales@crestflousa.com · +1 346 594 9005
Also known as: ASTM A276 designations & related terms
Specifications and buyers write this standard many ways. The names below all point back to the same specification and its grades.
| Category | Terms covered |
|---|---|
| Primary designation | ASTM A276, A276, ASTM-A276, ASTM International A276 |
| Metric companion | ASTM A276/A276M, A276M, A 276, A276/A276M (M = SI / metric units) |
| Revision forms | ASTM A276-23, A276/A276M-23, A276 latest revision, A276-17, A276-16a, A276-15 |
| Full title | "Standard Specification for Stainless Steel Bars and Shapes" |
| Grade / UNS call-outs | A276 Type 304, A276 316, A276 316L, A276 Type 410, A276 430, A276 UNS S31600, A276 S30400, A276 XM-19 |
| Product-form phrasings | A276 round bar, A276 flat bar, A276 square bar, A276 hex bar, A276 shapes, A276 cold finished bar, A276 hot finished bar, A276 cold drawn bar, A276 bright bar, A276 black bar |
| Common phrasings | A276 spec, A276 standard, A276 specification, A276 stainless bar, A276 material, A276 bar stock, stainless steel bars ASTM A276 |
Standard at a glance: ASTM A276 attributes
| Attribute | Value (standard published reference) |
|---|---|
| Designation | ASTM A276 / A276M (the M companion gives SI / metric units) |
| Full title | "Standard Specification for Stainless Steel Bars and Shapes" |
| Issuing body | ASTM International, Committee A01 on Steel, Stainless Steel and Related Alloys |
| Current edition | ASTM revises A276 periodically (recent editions include A276/A276M-23); cite the current published edition your project specification requires |
| Scope | Hot-finished or cold-finished stainless bars (rounds, squares, hexagons) and hot-rolled or extruded shapes (angles, tees, channels) for general use |
| Explicitly excludes | Bars and billets for reforging, reinforcing bar, wire, tube and pipe, and plate/sheet/strip (covered by A666) |
| Grade families | Austenitic, ferritic and martensitic stainless steels (and some age-hardenable grades) |
| Grade identification | By type designation plus UNS number (e.g. Type 316 = UNS S31600) |
| Conditions | Condition A (annealed); Condition H (hardened); Condition T (hardened and tempered) |
| Chemical composition | By the referenced grade's UNS chemistry, A276 invokes the grade, it does not define a stand-alone chemistry |
| Mechanical requirements | Tensile strength, yield strength, elongation, reduction of area and hardness, by grade and condition |
| General requirements / tolerances | Dimensional tolerances (including straightness and surface finish) and general requirements per ASTM A484 / A484M, which A276 references |
| Test methods | Tension and hardness testing per ASTM A370; chemical analysis per the standard |
| Related product-form specs | A479 (pressure-vessel bar), A582 (free-machining bar), A484 (general requirements), A666 (plate/sheet/strip), A182 (forgings), A213/A269/A312 (tube/pipe) |
This standard's complete grade table, along with its numeric acceptance figures, is copyrighted and governed by the current edition. This page just summarizes scope, grades and representative requirements rather than reproducing that document. Values follow the applicable standard and can be adjusted to fit requirements.
What is ASTM A276?
ASTM A276 / A276M is the ASTM International standard specification covering hot- and cold-finished stainless steel bars and shapes used as general machining stock. The full title reads "Standard Specification for Stainless Steel Bars and Shapes." That "/A276M" tag isn't a separate document; it just restates the same requirements in SI (metric) units. So A276 and A276M amount to one specification expressed in two unit systems.
A276 lays out the grades, supply conditions, and mechanical and hardness requirements for stainless bar meant for general engineering and machined components, everything from valve stems to fitting blanks. Chemistry comes from the referenced grade, not from A276 itself. Order 316 bar to A276 and the composition limits trace back to UNS S31600. A276 is the general-purpose bar spec, so it ends up broader, and less restrictive, than the pressure-vessel bar spec ASTM A479, which ASME adopts as SA-479.
ASTM A276 scope: bars and shapes as machining stock
The specification covers two product families, in both hot-finished and cold-finished conditions.
- Bars, round, square and hexagon.
- Shapes, hot-rolled or extruded angles, tees and channels.
A276 leaves out bars and billets meant for reforging, along with reinforcing bar, wire, tube and pipe, and flat-rolled plate, sheet and strip, all of which fall under A666. This is machining and fabrication stock, the raw material behind machined fluid-system components. It isn't a tube, forging or pressure-vessel specification.
Where can I get the ASTM A276 PDF?
ASTM International holds the copyright and sells the full standard through its official webstore. What follows here is a summary of A276's scope, grades and requirements for engineering reference; it doesn't reproduce or distribute the copyrighted document itself. Anyone doing compliance work should buy the current official edition. Unofficial "free download" copies might be outdated, so don't rely on them.
ASTM A276 grades covered: types & UNS numbers
A276 lays out three families of stainless: austenitic, ferritic and martensitic, each tagged by type and UNS number. The austenitic 300-series grades do most of the instrumentation work. Martensitic grades like 410 and 416 come into play where you need more hardness or strength, valve stems being a good example. Crestflo trains people on each grade but only ever supplies it as an instrumentation form, whether that's a valve, fitting, manifold or thermowell. Bar stock or mill product isn't part of the offering.
| Grade / Type | UNS No. | Family | Typical instrumentation use | Material reference |
|---|---|---|---|---|
| 304 | S30400 | Austenitic | General corrosion-resistant bodies & blanks | 304 / 304L |
| 304L | S30403 | Austenitic (low-carbon) | Welded / sensitization-prone service | 304 / 304L |
| 316 | S31600 | Austenitic (Mo-bearing) | Valve & fitting bodies in aggressive media | 316 / 316L |
| 316L | S31603 | Austenitic (low-carbon) | Most-specified instrumentation grade | 316 / 316L |
| 321 / 347 | S32100 / S34700 | Austenitic (stabilized) | Elevated-temperature service | — |
| XM-19 (Nitronic 50) | S20910 | High-strength austenitic | High-strength, corrosion-resistant stems | — |
| 410 | S41000 | Martensitic | Hardenable stems & trim | — |
| 416 | S41600 | Martensitic (free-machining) | Machined stems & small parts | — |
| 431 | S43100 | Martensitic (high-strength) | High-strength shafts & stems | — |
| 430 | S43000 | Ferritic | General ferritic service | — |
| 446 | S44600 | Ferritic (heat-resistant) | Oxidation-resistant components | — |
The full grade list runs longer than what's shown here; it's fixed by the current edition of the standard. A276 also covers additional austenitic grades (302, 305, 309, 310, 317), ferritic grades (405, 429, 434) and martensitic grades (403, 414, 420, 440A/B/C). Check any specific grade against that edition. Values follow the applicable standard and can be adjusted to requirement.
ASTM A276 Type 304 & Type 316 (the common austenitic grades)
A276 Type 304 (UNS S30400) is the workhorse 18Cr-8Ni austenitic bar grade, specified wherever general corrosion resistance is enough. 304L (S30403) trims the carbon content, which keeps it from sensitizing during welding. Type 316 (S31600) brings molybdenum into the mix for better pitting resistance, and 316L (S31603) is the low-carbon counterpart. It's the grade most engineers reach for when specifying instrumentation in aggressive media.
For composition, properties and grade selection, check the 316 / 316L material page and the 304 / 304L material page. Need help choosing between them? The 304 vs 316 comparison lays out the differences.
ASTM A276 Type 410 & martensitic grades
A276 also deals with martensitic grades: 410 (S41000), the free-machining 416 (S41600), and higher-strength 431 (S43100). All three harden through heat treatment. Engineers call for them when a component needs more hardness or strength than an austenitic grade can offer, valve stems and trim being a good example, and they ship in the hardened (H) or hardened-and-tempered (T) condition rather than annealed.
ASTM A276 conditions: A (annealed), H (hardened), T (hardened & tempered)
A276 supplies the bar in defined heat-treatment conditions, and that condition sets the mechanical and hardness limits that apply.
| Condition | Meaning | Typically applies to |
|---|---|---|
| Condition A | Annealed, the softened supply condition | Austenitic and ferritic grades (e.g. 304, 316, 430) |
| Condition H | Hardened by heat treatment | Hardenable martensitic grades (e.g. 410, 416, 431) |
| Condition T | Hardened and tempered | Hardenable martensitic grades requiring tempered properties |
Condition A (annealed or solution-annealed) is the standard austenitic supply condition. Cold-worked or cold-drawn finishes, along with hardenable martensitic grades, can be ordered instead in Condition H or T. Values follow the applicable standard and can be adjusted to requirement.
ASTM A276 mechanical & hardness requirements (representative Condition A limits)
A276 spells out the minimums a grade and condition must hit: tensile strength, yield strength, elongation, reduction of area, plus a hardness ceiling. The table below gives representative annealed (Condition A) minima for the common austenitic grades.
| Grade | Tensile min | Yield min (0.2% offset) | Elongation min | Hardness max |
|---|---|---|---|---|
| 304 / 304L | 75 ksi (515 MPa) | 30 ksi (205 MPa) | 40% | ~201 HBW / 92 HRB |
| 316 | 75 ksi (515 MPa) | 30 ksi (205 MPa) | 40% | ~217 HBW / 95 HRB |
| 316L | 70 ksi (485 MPa) | 25 ksi (170 MPa) | 40% | ~217 HBW / 95 HRB |
Hardness limits shift with grade, section size and condition, and the current A276 edition sets those figures. Austenitic grades are capped in HBW (Brinell) or HRB (Rockwell B); hardened martensitic grades like 410, 416 and 431 are limited in HRC (Rockwell C) instead. Physical properties like density (about 8.0 g/cm³ for austenitics) come from the grade itself, not from A276. Values follow the applicable standard and can be adjusted to requirement, so check the governing limits against whichever edition your specification cites.
ASTM A276 chemical composition: specified by referenced grade
A276 doesn't spell out its own chemistry. Instead, it invokes each grade's UNS composition limits, so the composition of A276 Type 316 bar is simply the composition of UNS S31600. Below are representative nominal ranges (weight %) for the common austenitic grades. For full per-grade limits and corrosion data, check the material pages.
| Grade (UNS) | C max | Cr | Ni | Mo |
|---|---|---|---|---|
| 304 (S30400) | 0.08 | 18.0–20.0 | 8.0–10.5 | — |
| 304L (S30403) | 0.030 | 18.0–20.0 | 8.0–12.0 | — |
| 316 (S31600) | 0.08 | 16.0–18.0 | 10.0–14.0 | 2.0–3.0 |
| 316L (S31603) | 0.030 | 16.0–18.0 | 10.0–14.0 | 2.0–3.0 |
Full per-grade limits, including Mn, Si, P, S and N, come from the referenced UNS grade chemistry. As for international equivalents, treat the EN/DIN Werkstoff and JIS cross-references as directional only: 316 lines up with EN 1.4401 (W.Nr. 1.4401, JIS SUS316), 316L with EN 1.4404, 304 with EN 1.4301 (JIS SUS304), and 304L with EN 1.4307. Check the governing specification before treating any of these as an exact match across standards. The whole thing can be adjusted to suit requirements.
ASTM A276 vs A479 vs A582 vs A484: related specifications
The stainless bar specs mostly come down to product qualification and general-requirements role, not grade. The same UNS chemistry can show up across every one of them.
| Specification | Covers | Typical use | Differs from A276 by |
|---|---|---|---|
| ASTM A276 | Stainless bars & shapes (general) | General machining stock, the material Crestflo machines | — |
| ASTM A479 | Stainless bars & shapes for boilers & pressure vessels | Pressure-retaining components; adopted as ASME SA-479 | Pressure-vessel-qualified; code-adopted, stricter |
| ASTM A582 | Free-machining stainless bars | High-volume screw-machine parts | Free-machining grades optimized for machinability |
| ASTM A484 | General requirements for stainless bars, billets & forgings | Tolerances, testing & general rules A276 references | The umbrella general-requirements spec, not a product spec |
| ASTM A666 | Stainless plate, sheet & strip | Flat-rolled product | Different product form (flat-rolled, not bar) |
In short: A276 covers general-purpose stainless bar and shapes. A479 (SA-479) is for pressure-vessel-qualified bar and shapes. A582 handles free-machining bar. A484 is the general-requirements umbrella that A276 references. Match by UNS number first, then by whatever specification your service and code demand. There's no single "equivalent" to A276, equivalence runs by grade, meaning the same UNS chemistry showing up in another spec or form. See the A276 vs A479 detail, and for forged product, check ASTM A182.
Related standards & product forms
A276 belongs to a family of stainless product-form specifications. To pick the right one, start with the product form your part actually needs.
| Standard | Product form | Reference page |
|---|---|---|
| ASTM A276 | General stainless bars & shapes | This page |
| ASTM A479 | Bars & shapes for pressure vessels (SA-479) | ASTM A479 |
| ASTM A182 | Forgings, flanges, forged fittings | ASTM A182 |
| ASTM A213 | Seamless ferritic/austenitic boiler & heat-exchanger tube | ASTM A213 |
| ASTM A269 | Seamless & welded austenitic instrumentation tubing | ASTM A269 |
| ASTM A312 | Seamless & welded austenitic pipe | ASTM A312 |
For sour service, A276 grade selection carries NACE MR0175 / ISO 15156 requirements on top of the base spec. A bar spec alone won't get you sour-service compliance. Check the sour-service selection guide for details.
ASTM A276 testing, traceability & NACE conformance
Crestflo adds documentation and verification a QA or spec reviewer needs before signing off on a delivered part, on top of what A276 itself demands. A276 calls for tension and hardness testing (per ASTM A370), chemical analysis and product marking to the grade.
| Requirement | How Crestflo satisfies it |
|---|---|
| Grade verification | PMI (positive material identification) on the delivered component, in addition to the mill's heat and product analysis |
| Mechanical / condition proof | Annealed (Condition A) for austenitic grades, or hardened (H / T) for martensitic grades; tensile and hardness reportable to requirement |
| Documentation / traceability | EN 10204 3.1 material test certificate as standard (3.2 on request), with a heat/lot number on every part |
| Independent verification | In-house NDT; destructive testing at ISO/IEC 17025-accredited labs; third-party inspection on request |
| Sour-service overlay | Where the service is sour, grades supplied to NACE MR0175 / ISO 15156 hardness and material requirements, with the qualified condition documented |
Full EN 10204 MTC mechanics and our country-of-origin & TAA position each get their own page. Need datasheets or CAD models? Customers can request them directly.
Crestflo instrumentation parts machined from A276-family bar
Crestflo doesn't sell A276 bar as raw stock. What it does is machine finished instrumentation components from A276-family stainless and alloy bar, so the part carries the invoked ASTM grade and its certification, and it arrives ready to install.
| Crestflo component | Typical bar grade | Certification |
|---|---|---|
| Bar-stock & forged valve bodies and stems | 316/316L, 304/304L, 410, 431, XM-19 | EN 10204 3.1 MTC (3.2 on request), heat number, PMI |
| Manifold bodies (2 / 3 / 5-valve) | 316/316L, 6Mo, duplex | 3.1 MTC, 100% seat & shell leak test |
| Compression tube fitting bodies | 316/316L, high-nickel alloys, titanium | 3.1 MTC, tested for interchange per ASTM F1387 |
| Bar-stock thermowells | 316/316L, 304/304L | 3.1 MTC, heat number |
- Instrumentation valve bodies: needle, ball, check/NRV and bleed valves, offered in bar-stock and forged-body construction. They're qualified to the applicable valve standards, ASME B16.34 and API, not the compression-fitting standard.
- Manifold bodies: 2-valve, 3-valve and 5-valve configurations. Every one gets 100% seat and shell leak testing.
- Compression tube fitting bodies: machined from A276-family bar and tested for interchange per ASTM F1387. Available in imperial and metric sizes, up to 2" (50 mm) OD.
- Bar-stock thermowells: flanged and threaded, machined from solid bar. Lengths run up to 1 m.
Grades in the families above are available across these forms, from 316/316L and 304/304L to 904L, Duplex 2205 and high-nickel alloys, supplied only as instrumentation components, not bar, sheet or plate.
Why Crestflo for A276-conforming instrumentation
The pedigree is on the paper. Components come machined from A276-family bar. Each one ships with an EN 10204 3.1 MTC (3.2 on request) and a heat number stamped on every part, so the traceability a spec or QA audit demands is already there.
The A276 grades actually cover the range. Think 304/304L, 316/316L, 410/431 martensitics, XM-19, and others, all supplied as finished instrumentation forms.
It's a drop-in replacement, and it's proven. Fittings get tested for interchange per ASTM F1387. Valves and manifolds are qualified to ASME B16.34 / API. A spec'd line can be swapped out without a redesign.
Lead time is what actually moves projects along. Standard items sit in ready stock; specials get made to order. Delivery runs 6-8 weeks, against the 20-plus weeks that's typical from the majors.
- Honest origin. Indian origin; US / European melt available on request, with full material traceability.
- Small MOQ and private label, both imperial and metric, customizable to requirement.
- Certified quality system: ISO 9001 / 14001 / 45001 & PED certified.
Crestflo is the instrumentation arm of a four-decade-old export house recognized by the Government of India, with a long track record delivering across the Middle East. It's a manufacturing pedigree behind a focused, US-serving instrumentation brand. We Engineer Confidence.
Request an ASTM A276 quote
Send your requirement to Crestflo's Engineering Team, grade/UNS, product form, size and quantity, plus any condition (A / H / T) or NACE overlay, and they'll confirm the conforming grade, condition and documentation for your part.
RFQ, tell us what you need:
- Name
- Company name
- Phone
- Requirement description (product, grade, size, quantity, service conditions)
Secondary paths: request a sample · become a distributor · contact Crestflo.
US contact: sales@crestflousa.com · +1 346 594 9005 · Houston, TX.
Frequently asked questions
What is ASTM A276?
ASTM A276 / A276M is the ASTM International standard covering hot- and cold-finished stainless steel bars, whether round, square, or hexagonal, along with shapes like angles, tees, and channels meant for general machining stock. It lays out the grades, supply conditions, and mechanical and hardness requirements. Chemistry, though, comes from the referenced grade, not from A276 itself.
What is the difference between ASTM A276 and ASTM A479?
Both cover stainless bars and shapes, but A276 is the general-purpose specification. A479 covers bars and shapes meant for boilers and other pressure vessels, and it's been adopted into the ASME code as SA-479. Order pressure-vessel work to A479 / SA-479. General machining stock gets ordered to A276.
What does ASTM A276 specify for Type 304 stainless steel?
For Type 304 (UNS S30400) in the annealed condition, A276 sets minimum tensile and yield strength, minimum elongation and a maximum hardness. Representative annealed limits run around 75 ksi tensile, 30 ksi yield, 40% elongation and roughly 201 HBW. Check the exact figures against the current edition. See the 304 / 304L material page.
What grades does ASTM A276 cover?
Austenitic grades (304, 304L, 316, 316L, 321, 347, XM-19), ferritic grades (430, 446) and martensitic grades (410, 416, 431) round out the list, each tagged by type and UNS number. The current edition fixes the complete list; consult the grade table above for the full picture.
What is Condition A in ASTM A276?
Condition A stands for annealed, the softened supply condition standard for austenitic and ferritic grades. Hardenable martensitic grades, on the other hand, can be supplied hardened (Condition H) or hardened-and-tempered (Condition T) instead.
Does ASTM A276 define chemical composition?
Not by itself. A276 pulls in the composition limits of the grade it references, so the makeup of A276 Type 316 bar matches UNS S31600. For the full composition and corrosion data, check the relevant material page, such as 316 / 316L or 304 / 304L.
Is A286 the same as 18/8 stainless steel?
No. "18/8" describes roughly 18% chromium / 8% nickel austenitic stainless, such as Type 304. A286 (UNS S66286) is different: an iron-nickel-chromium precipitation-hardening superalloy. It isn't 18/8, and it isn't the same thing as the ASTM A276 standard either.
What is the latest edition of ASTM A276?
ASTM revises A276 on a periodic basis, and recent editions include A276/A276M-23. Confirm the current published edition against the ASTM catalog. Cite the revision your project specification requires, because edition references vary by contract.
Is ASTM A276 bar suitable for sour (H₂S) service?
A276 sets the bar's grade and mechanical requirements, but it doesn't by itself confer sour-service compliance. For H₂S service, the material and its hardness must also meet NACE MR0175 / ISO 15156, a standard Crestflo can supply to, with the qualified condition documented.
Does Crestflo supply parts made from A276-conforming bar with certification?
Crestflo machines instrumentation valve bodies, stems, fitting bodies, manifold bodies and bar-stock thermowells from A276-family stainless and alloy bar. Every part ships with an EN 10204 3.1 MTC, 3.2 available on request, and heat-number traceability comes standard. PMI is available too. Crestflo supplies finished instrumentation components, not raw bar or mill product.
Where can I download the ASTM A276 PDF?
ASTM International owns the copyright on the full standard and sells it through its official webstore. This page just summarizes A276's scope, grades and requirements; it doesn't reproduce or distribute the document itself.
Explore related standards, materials & products
Standards: Standards hub · ASTM A479 · ASTM A182 · ASTM A213 · ASTM A269 · ASTM A312 · ASME B16.34 · NACE MR0175 · EN 10204 MTC
Materials: 316 / 316L · 304 / 304L · 904L · Duplex 2205 · Super Duplex 2507 · Alloy 20
Products: Instrumentation valves · Tube fittings · Thermowells · 3-valve manifold
Guides: 304 vs 316 · 316 vs 316L · material selection by service