- Grade / Alloy
- 1.4762
- EN / W.Nr.
- 1.4762X10CrAlSi25 / X10CrAl24
- AISI / SAE
- —
- UNS
- —
- Family
- Ferritic
Chemical composition
Chemical composition
Composition limitsComposition limits for heat-resisting steels within EN 10095.
| Element | Content (% by mass) |
|---|---|
| CCarbon | ≤ 0.12 |
| SiSilicon | 0.7–1.4 |
| MnManganese | ≤ 1 |
| PPhosphorus | ≤ 0.04 |
| SSulfur | ≤ 0.015 |
| CrChromium | 23–26 |
| AlAluminium | 1.2–1.7 |
Values describe the grade, not the analysis of a specific batch. The applicable product specification and material certificate determine acceptance. A dash does not mean zero.
What is 1.4762?
1.4762 is a high-chromium ferritic heat-resistant steel identified as X10CrAlSi25. Aluminium and silicon contribute to the protective role of chromium in hot service. Its applications are particularly associated with equipment exposed to hot gases. It belongs to the same broad material group as 1.4742 but has higher chromium content. Grade 1.4749, known as 446, can appear in related applications but has a different chemical definition.
Its role in sulfur-bearing gas environments
Hot-gas composition can change the properties required of metal in furnace and energy systems. The widespread use of nickel-bearing austenitic grades does not mean that one family suits every hot atmosphere. 1.4762 is a recognised ferritic option for elevated-temperature applications involving sulfur-bearing gases. Surface resistance in contact with the gas is an important part of its role. Carrying heavy mechanical loads at high temperature is a different property and cannot be inferred from gas resistance alone.
Low expansion in furnace components
Ferritic steels expand less with temperature than common austenitic stainless grades. This difference can be useful in a plate extending across a hot chamber or a component directing gas flow. The thermal behaviour of 1.4762 therefore matters alongside its high-chromium composition. Furnace internals, hot-gas baffles and protective components depend not only on their strength but also on how their dimensions change as temperature varies.
Why are 1.4762 and 446 separate grades?
Both materials have high chromium and heat-resistant characteristics, but that does not make them one alloy. 1.4762 belongs to the chromium-aluminium-silicon group, while 446 / 1.4749 is defined by different chemical limits. Their appearance side by side in commercial tables does not change the distinction. The difference between 1.4742 and 1.4762 is likewise more than a name. These grades address related hot-gas duties through separate alloy compositions.
Typical application areas
Furnace equipment, hot-gas elements and heat-protective components.
Product and cutting options
Relevant product forms for this material are listed below. Availability varies with grade and dimensions.