AZ31B: Wrought Magnesium Alloy for Lightweight Structural Sheet and Plate
ASTM B90 · Published: 2026-06-03 · Updated: July 2026
AZ31B (3% Al, 1% Zn) is the most widely used wrought magnesium alloy — the lowest-density structural metal commercially available (1.77 g/cm³, 33% lighter than aluminum). It is used for aircraft interior structures, laptop cases, camera bodies,...
AZ31B (3% Al, 1% Zn) is the most widely used wrought magnesium alloy — the lowest-density structural metal commercially available (1.77 g/cm³, 33% lighter than aluminum). It is used for aircraft interior structures, laptop cases, camera bodies, and automotive components where every gram of weight savings matters.
Quick Facts
| Category | Magnesium Alloy |
| Standard | ASTM B90 |
| Density | 1.77 g/cm³ |
| Yield Strength | 200 MPa |
| Tensile Strength | 255 MPa |
Global Equivalents & Cross-Reference
Related Materials
🧮 Material Weight Calculator
Calculate the weight based on this material's density: 1.77 g/cm³
Frequently Asked Questions
What are the limitations of magnesium alloys?
(1) Hexagonal close-packed (HCP) crystal structure limits cold formability — most forming must be done warm (200-300°C). (2) High reactivity — magnesium chips and dust are flammable; machining requires Class D fire extinguishers. (3) Galvanic corrosion — magnesium must be electrically isolated from steel fasteners with washers or coatings. (4) Higher raw material cost than aluminum.
References & International Standards
- ASTM International. Standard Specifications for Steel & Metal Alloys. astm.org
- International Organization for Standardization (ISO). Metallic Materials — Cross-Reference Database. iso.org
- American Iron and Steel Institute (AISI). Steel Grade Designations & Equivalents. steel.org
- European Committee for Standardization (CEN). EN Steel Standards & Numbering System. cencenelec.eu