310S — what the data actually supports

Data completeness: partial. Last verified 19 August 2026.

Designations

310S is bought for what it does hot, so this page carries elevated temperature rows and no room temperature ones — the datasheet consulted has no room temperature mechanical table at all, which is itself the most honest thing it says about the grade. Twenty-five percent chromium builds an oxide scale that survives to 1050 °C in air; the nineteen percent nickel keeps the structure austenitic while it does so.

Properties, with what each one rests on

7 sourced values, 4 gaps named. Publishing the gaps is more useful than filling them from an aggregator that does not say where its numbers came from. The routes to filling them are the standard itself, a mill datasheet, or a mill certificate for your actual heat — which supersedes both at E5.

Where the numbers come from

Maximum service temperature in air. This is the mill’s own recommendation printed in its datasheet, not a limit set by a standard, and it is quoted for air. Change the atmosphere — sulphur, carburising, cyclic heating — and the number moves, in the wrong direction. Do not carry it onto a drawing without the atmosphere written next to it.

Proof strength Rp0.2, minimum at 100 °C. The table is headed as EN 10095 minimum values. Note what it implies: at 100 °C this grade is already weaker than plain 304 is at room temperature. Heat resistance is about scale, not about strength.

Proof strength Rp0.2, minimum at 600 °C. Forty percent of the figure the same EN 10095 table gives at 100 °C. Above roughly 600 °C the governing property stops being yield and becomes creep, which no source on this page supplies.

Why we do not just copy an aggregator. Because then this page would be a worse copy of MatWeb with no way for you to tell which rows to trust, and the one thing we have that MatWeb does not is the evidence column. Our coverage and its limits.

What 310S is usually chosen for

Furnace internals, radiant tubes, burner components, kiln furniture and heat treatment fixtures — the parts that live in a hot oxidising atmosphere and are replaced on a schedule rather than designed for a service life. Its high chromium and nickel keep the scale adherent through cycling, and that is what it is bought for.

And what it is usually rejected for

Sulphur, carburising atmospheres and cost. Nickel forms low-melting sulphides, so the same composition that makes 310S good in air makes it poor in a sulphur-bearing flue. It also embrittles after long exposure in the sigma phase range, so a part that has to be handled cold after service is a bad application.

The number to be more careful with than any of the above is the difference between a specified minimum and a typical value — a floor the standard guarantees, versus what a supplier’s production usually does. The full version, and the most expensive routine mistake in material data.

Compare

310S vs 253ma

What this page does not cover

• No room temperature values at all, which is the datasheet’s position, not an omission on this page.
• No creep or creep rupture data, which governs design above roughly 600 °C.
• The maximum service temperature is a supplier recommendation for air, not a standard limit.
• No sulphidation or carburisation data.
• Composition limits, not established.

Generated from data/materials/310s.yaml. Regenerate rather than editing this file by hand — edits here are lost on the next build.