---
title: "304 Stainless Steel Threaded Bar, M6 to M45 | Laxcon Steels"
source: "https://www.laxconsteels.com/products/threaded-bars/aisi-304/"
description: "AISI 304 stainless steel threaded bar, M6 to M45, made to order by Laxcon Steels, India: composition, equivalents, standards and what the order states."
---
# AISI 304 Threaded Bars

*[Home](https://www.laxconsteels.com/) > [Products](https://www.laxconsteels.com/products/) > [Threaded Bars](https://www.laxconsteels.com/products/threaded-bars/) > AISI 304*

AISI 304 threaded bar is fully threaded 18/8 stainless bar, M6 to M45, used for hangers, tie rods and anchor fixings.

M6 to M45 Austenitic stainless steel Made to order

## AISI 304 threaded bar

AISI 304 threaded bar is bar rolled in the general purpose austenitic stainless steel and threaded along its whole length, M6 to M45, or 1/4 to 1-3/4 inch, in lengths to 6 metres. The chromium forms the passive oxide film that keeps the thread from rusting in air, water and food service, and the nickel holds the austenitic structure. The grade carries no deliberate molybdenum, so where the fixing sits in seawater, de-icing salt or a chloride process stream, 316 threaded bar in class A4 resists pitting better and is the usual step up. Where a long welded assembly cannot be annealed afterwards, the lower carbon of 304L is chosen instead. For dry, damp and mild outdoor fixing work 304 covers the duty. Laxcon Steels rolls the thread to order.

The bar is supplied solution annealed, heated and cooled fast so the chromium carbides return into solution, which leaves it soft, ductile and non-magnetic. It cannot be hardened by heat treatment and takes strength only from cold work, and rolling the thread is itself cold work, so a rolled thread is stronger than a cut one and can read slightly magnetic. ISO 3506-1 sets class A2-70 at 700 MPa tensile strength and 450 MPa proof strength, and the annealed class A2-50 at 500 MPa and 210 MPa. ASTM A193 grade B8 Class 1 is carbide solution treated at 515 MPa tensile and 205 MPa yield. Typical uses are pipe hangers and building services supports, tie and anchor rods, frames in dairy and food plant, and studs cut to length.

Composition limits in weight percent are carbon 0.08 maximum, manganese 2.0 maximum, sulphur 0.03 maximum, phosphorus 0.045 maximum, silicon 0.75 maximum, chromium 18.0 to 20.0, nickel 8.0 to 10.5 and nitrogen 0.1 maximum.

## AISI 304 threaded bar supply conditions

| Property | Value |
| --- | --- |
| Size range | M 6 - M 45 (1/4" - 1-3/4") |
| Threading Method | Thread Rolling |
| Threading condition | Fully Threaded |
| Tolerance | ASME B1.1 & B1.13M |
| Thread Type | ANSI B1.1 Class 2A Fit |
| Length | Up to 6 metres |
| Grade | AISI 304 (304, SS 304, SUS 304, 1.4301) |
| Family | Austenitic stainless steel |
| Supply | Made to order in this grade; every published size of the form |

## Composition of AISI 304

| Element | Symbol | Minimum % | Maximum % |
| --- | --- | --- | --- |
| Carbon | C |  | 0.08 |
| Manganese | Mn |  | 2.0 |
| Sulphur | S |  | 0.03 |
| Phosphorus | P |  | 0.045 |
| Silicon | Si |  | 0.75 |
| Chromium | Cr | 18.0 | 20.0 |
| Nickel | Ni | 8.0 | 10.5 |
| Nitrogen | N |  | 0.1 |

Composition, weight percent, balance iron. From the Laxcon Steels grade reference.

## Equivalents of AISI 304

| Standard | Designation |
| --- | --- |
| UNS | S30400 |
| EN number | 1.4301 (X5CrNi18-10) |
| JIS | SUS 304 |

Equivalence means nearest counterpart, not identity: each standards body sets its own composition window, so the limits of the standard named on the order govern.

## Pitting resistance

The pitting resistance equivalent number of AISI 304 runs from 18.0 at the specified minimum chromium, molybdenum and nitrogen to 21.6 at the maxima, computed as PREN = Cr + 3.3Mo + 16N (International Molybdenum Association). It ranks resistance to chloride pitting against other austenitic and duplex grades and nothing else: it does not predict crevice corrosion, stress corrosion cracking or service life. The [pitting resistance reference](https://www.laxconsteels.com/grades/pitting-resistance/) carries the full table.

## Governing standards

| Property | Value |
| --- | --- |
| ISO 3506-1 | Mechanical properties of corrosion-resistant stainless steel fasteners: the A2-70, A2-80, A4-70 and A4-80 property classes. |
| ASTM A193/A193M | Alloy-steel and stainless steel bolting for high temperature or high pressure service: the B8 and B8M classes. |
| ASME B1.1 | Unified inch screw threads: the 2A external thread class. |
| ASME B1.13M | Metric screw threads, M profile. |
| EN 10088-3 | Stainless steels: technical delivery conditions for semi-finished products, bars, rods, wire, sections and bright products for general purposes. Composition, heat treatment condition and mechanical properties per grade. |
| EN 10204 | Metallic products, types of inspection documents: the 2.2 test report and the 3.1 and 3.2 inspection certificates a purchase order can call for. |

## Property classes of AISI 304 threaded bar

| Marking | Standard | Minimum tensile strength | Minimum 0.2 percent proof stress | Condition |
| --- | --- | --- | --- | --- |
| A2-50 | ISO 3506-1 | 500 MPa | 210 MPa | annealed |
| A2-70 | ISO 3506-1 | 700 MPa | 450 MPa | cold worked |
| A2-80 | ISO 3506-1 | 800 MPa | 600 MPa | high strength cold worked |
| B8 Class 1 | ASTM A193 | 515 MPa | 205 MPa | carbide solution treated |
| B8 Class 2 (up to 19 mm) | ASTM A193 | 860 MPa | 655 MPa | solution treated and strain hardened |

ISO 3506-1 classes apply to thread diameters up to M39 for class 50 and to M24 for classes 70 and 80 unless the standard's larger-diameter tables are invoked; ASTM A193 Class 2 properties fall with diameter above 19 mm.

## Ordering AISI 304 threaded bar

An enquiry for this bar states the grade and governing standard (AISI 304 to ISO 3506-1 or ASTM A193 grade B8, with EN 10088-3 for the bar itself), the property class and condition, the thread size and form to ASME B1.13M or ASME B1.1 class 2A, the cut length within the 6 metre maximum, the quantity, the certificate type to EN 10204, and any test to be reported, such as PMI confirmation of grade.

## Other grades in Threaded Bars

- [**AISI 316** The molybdenum-bearing austenitic grade](https://www.laxconsteels.com/products/threaded-bars/aisi-316/)

## AISI 304 in other forms

- [**Hot Rolled Round Bars** hot rolled round bar](https://www.laxconsteels.com/products/hot-rolled-round-bars/aisi-304/)
- [**HRAP Flat Bars** flat bar](https://www.laxconsteels.com/products/hrap-flat-bars/aisi-304/)
- [**HRAP Equal Angles** equal angle](https://www.laxconsteels.com/products/hrap-equal-angles/aisi-304/)
- [**Channels** channel](https://www.laxconsteels.com/products/channels/aisi-304/)
- [**Square Bright Bars** square bright bar](https://www.laxconsteels.com/products/square-bright-bars/aisi-304/)
- [**Hexagonal Bright Bars** hexagonal bright bar](https://www.laxconsteels.com/products/hexagonal-bright-bars/aisi-304/)

[Threaded Bars: every size](https://www.laxconsteels.com/products/threaded-bars/) [AISI 304 composition and equivalents](https://www.laxconsteels.com/grades/aisi-304/) [Weight calculator](https://www.laxconsteels.com/weight-calculator/) [Send the RFQ](https://www.laxconsteels.com/contact/?product=threaded-bars)