AISI 310 stainless steel is a high-alloy austenitic stainless steel developed for oxidation resistance and mechanical stability at elevated temperatures. Its characteristic 25Cr-20Ni chemistry gives it substantially higher chromium and nickel content than common 304 stainless steel. This data sheet focuses on the material's chemical composition, annealed mechanical properties, physical properties, high-temperature behavior, fabrication characteristics, and applicable ASTM product standards.

AISI 310 Chemical Composition

The high chromium and nickel content is the defining feature of this alloy. Chromium supports the formation of a protective oxide scale during high-temperature exposure, while nickel stabilizes the austenitic structure and contributes to toughness and elevated-temperature performance.

These values represent commonly published Type 310 chemistry limits. The applicable ASTM specification should be used for the final chemical acceptance criteria because requirements can differ by product form and specification. ([bssa.org.uk](https://bssa.org.uk/bssa_articles/chemical-compositions-of-aisi-astm-asme-and-uns-austenitic-stainless-steel-grades/?utm_source=chatgpt.com))

Annealed Mechanical Properties

310 is normally supplied in an annealed condition for many flat-product applications. Annealing restores a stable austenitic structure and improves ductility after processing. Representative minimum mechanical requirements for commonly specified flat products are shown below.

These figures should be read as specification-oriented reference values rather than guaranteed properties for every product. Thickness, product form, testing direction, and the governing ASTM standard can affect the stated requirements. A mill test certificate should be used when a project requires certified mechanical results.

Physical Properties

The physical properties of 310 are important when the material is used in furnace structures, heat shields, heat-treatment fixtures, and components exposed to repeated temperature changes. Its density is higher than that of many common stainless grades because of its high alloy content.

The thermal expansion coefficient is temperature dependent, so a single value should not be used for detailed thermal-stress calculations across a wide temperature range. For precision furnace or heat-treatment designs, temperature-specific material data should be used.

Elevated-Temperature Properties

The main engineering advantage of 310 appears at elevated temperature. The high Cr-Ni alloy system provides good resistance to oxidation and scaling, while the austenitic matrix retains useful strength and toughness during heating.

For long-term exposure around 1000°C, however, oxidation resistance and mechanical strength should be considered separately. A material can resist surface oxidation while its load-bearing capability is progressively reduced by creep. Therefore, components carrying sustained loads at high temperature require creep and stress-rupture data rather than room-temperature tensile values alone.

Published technical references commonly place the oxidation-resistance capability of 310 near the 1100°C range under suitable conditions. This should not be interpreted as a universal allowable design temperature. Atmosphere, exposure time, component geometry, loading, thermal cycling, and surface condition all influence actual service life. ([sandmeyersteel.com](https://www.sandmeyersteel.com/alloy-310-310s-310h/?utm_source=chatgpt.com))

Creep and Long-Term High-Temperature Loading

Creep becomes an important design consideration when 310 components remain under stress for long periods at elevated temperatures. Creep is time-dependent deformation caused by sustained stress at high temperature. It can occur even when the applied stress is below the room-temperature yield strength.

For components such as furnace supports, racks, retorts, and structural fixtures, the designer should obtain temperature-specific creep or stress-rupture data whenever long-term loading is involved. A room-temperature tensile value such as 515 MPa does not describe the allowable stress at 1000°C.

Welding Characteristics

310 can be welded using conventional austenitic stainless-steel welding processes. TIG, MIG, and shielded metal arc welding are commonly used, with filler metals selected according to the base-metal grade, joint design, service temperature, and required properties.

For welding a 310 component, matching or appropriately selected 310-series filler metal is often considered when the weld must maintain comparable high-temperature performance. The exact filler should be confirmed from the welding procedure specification because oxidation environment, service temperature, joint restraint, and code requirements can change the preferred consumable.

Machining and Work Hardening

Machining 310 requires more attention than machining many carbon steels because austenitic stainless steel tends to work harden. If the cutting tool repeatedly rubs over the surface without maintaining sufficient cutting action, a hardened layer can develop and make subsequent cutting more difficult.

• Use sharp, rigid cutting tools.
• Maintain a positive cutting action instead of allowing prolonged rubbing.
• Apply appropriate cutting speed and feed for the selected tool material.
• Use adequate coolant where appropriate.
• Maintain stable workholding to minimize vibration and dimensional variation.

For precision components, machining parameters should be established according to the material condition, tooling system, geometry, and required surface finish rather than using generic carbon-steel cutting data.

ASTM Standards by Product Form

The correct ASTM specification depends on the product form. AISI 310 identifies the alloy, while the ASTM document establishes requirements for a particular product type.

ASTM A240, A312, and A276 should not be treated as interchangeable specifications. Each establishes requirements appropriate to a different product form. The purchase order should therefore state both the material grade and the applicable ASTM standard.

AISI 310 Purchasing Checklist

For industrial procurement, a complete specification prevents many material-identification problems. Buyers should confirm the following items before placing an order:

1. Grade: AISI Type 310 / UNS S31000.
2. Product standard: ASTM A240, A312, A276, or another applicable specification.
3. Product form: plate, sheet, coil, pipe, tube, bar, or fabricated component.
4. Dimensions: thickness, width, length, outside diameter, wall thickness, or bar diameter.
5. Surface: finish and surface condition appropriate to the application.
6. Heat treatment: annealed condition where required.
7. Inspection: chemical analysis, mechanical testing, dimensional inspection, and certification requirements.
8. Application: operating temperature, atmosphere, thermal cycling, and mechanical loading.

Industrial Supply of AISI 310 Stainless Steel

For industrial projects requiring multiple stainless grades or customized product forms, stainless steel products can be sourced according to the specified grade, dimensions, surface condition, and inspection requirements. Teda Ganghua provides stainless steel supply and processing support for industrial buyers, covering flat products, coils, pipes, tubes, bars, and related stainless-steel requirements.

When requesting a quotation or production confirmation, it is useful to provide the complete material designation together with dimensions, quantity, surface finish, service temperature, and certification requirements. This allows the material to be evaluated against the actual engineering application instead of relying only on the grade name.

Frequently Asked Questions

1. What is the chemical composition of AISI 310?

The main composition is approximately 24–26% chromium and 19–22% nickel, with carbon up to 0.25%, silicon up to 1.5%, and manganese up to 2.0%. Iron makes up the balance.

2. What are the mechanical properties of annealed AISI 310?

Common reference minimums for flat products include tensile strength of at least 515 MPa, yield strength of at least 205 MPa, and elongation of at least 40%. The exact values must be checked against the applicable product standard.

3. Can AISI 310 be used continuously at 1000°C?

It can be considered for high-temperature service around 1000°C when the atmosphere, loading, geometry, and thermal cycling are suitable. However, continuous temperature limits should be established from application-specific oxidation, creep, and stress-rupture data rather than from a single room-temperature property.

4. Which ASTM standard applies to AISI 310?

ASTM A240 is commonly used for plate, sheet, and strip. ASTM A312 covers stainless steel pipe, while ASTM A276 covers stainless steel bars. The correct standard depends on the product form.

5. Is AISI 310 difficult to machine?

It can be more difficult to machine than ordinary carbon steel because its austenitic structure can work harden. Sharp tooling, stable cutting conditions, suitable feeds and speeds, and effective cooling help reduce work-hardening problems.