- Grade / Alloy
- AZ31B
- EN / W.Nr.
- —
- AISI / SAE
- —
- UNS
- —
- Family
- Magnesium alloy
Chemical composition
Chemical composition
Composition limitsPublished principal alloying-element limits for AZ31B sheet, plate and coil; not a complete list of trace-element limits.
| Element | Content (% by mass) |
|---|---|
| AlAluminium | 2.5–3.5 |
| ZnZinc | 0.7–1.3 |
| MnManganese | 0.2–1 |
| MgMagnesium | Balance |
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 kind of material is AZ31B?
Magnesium is the base metal of AZ31B, with aluminium and zinc contributing to mechanical characteristics. At approximately 1.78 g/cm³, it is lighter than an equal volume of aluminium. This is useful where reducing component mass matters. Finished-part weight also depends on the thickness and geometry needed for its duty, but low density remains the central material advantage.
Applications where low weight matters
Portable equipment housings, vehicle parts and certain aerospace components are among its applications. Reducing mass can be valuable in parts that move or are handled frequently. Sheet and plate products suit lightweight bodies with large surfaces. The ability to contribute to low-weight components while retaining their mechanical function helps explain the established role of this alloy.
Surface and environment
Environmental moisture and salt matter alongside the low density of magnesium. AZ31B parts are used with suitable protective surfaces in many applications. Contact with other metals can also affect surface behaviour. Appropriate environmental protection therefore complements the mechanical characteristics of the alloy in a lightweight housing or other component.
Difference from AZ61 and AZ91
AZ31B differs from other magnesium alloys such as AZ61 and AZ91 in aluminium and zinc contents. These changes affect characteristics and product forms. Markings such as O and H24 on AZ31B sheet or plate identify material condition rather than separate alloys. The same grade can consequently be supplied in conditions offering different strength and formability.
Typical application areas
Lightweight equipment housings, aerospace and automotive parts.
Product and cutting options
Relevant product forms for this material are listed below. Availability varies with grade and dimensions.