AZ91C (M11914) Magnesium

AZ91C magnesium is an alloy of magnesium. AZ91C is the ASTM designation for this material. M11914 is the UNS number.

It has four common variants, each represented as a separate material. The Material Properties section below shows ranges encompassing all variants. For more specific values, follow the links in the Variant Materials section.

Material Properties

Base Metal Price20 % rel

Density1.9 g/cm3 (120 lb/ft3)

Elastic (Young's, Tensile) Modulus48 GPa (7.0 x 106 psi)

Elongation at Break2.3 to 8.1 %

Melting Onset (Solidus)470 °C (880 °F)

Modulus of Resilience (Unit Resilience)75 to 180 kJ/m3

Poisson's Ratio0.29

Solidification (Pattern Maker's) Shrinkage1.3 %

Specific Heat Capacity990 J/kg-K

Strength to Weight Ratio89 to 140 kN-m/kg

Tensile Strength: Ultimate (UTS)170 to 270 MPa (25 to 39 x 103 psi)

Tensile Strength: Yield (Proof)85 to 130 MPa (12 to 19 x 103 psi)

Thermal Expansion26 µm/m-K

Unit Rupture Work (Ultimate Resilience)3.3 to 3.6 MJ/m3

The length of each bar compares the given value to the highest value in the database.

Alloy Composition

Magnesium (Mg)88.6 to 91.4 %

Aluminum (Al)8.1 to 9.3 %

Zinc (Zn)0.4 to 1.0 %

Manganese (Mn)0.13 to 0.35 %

Residuals0 to 0.3 %

Silicon (Si)0 to 0.3 %

Copper (Cu)0 to 0.1 %

Nickel (Ni)0 to 0.010 %

Further Reading

ASTM B199: Standard Specification for Magnesium-Alloy Permanent Mold Castings

ASTM B403: Standard Specification for Magnesium-Alloy Investment Castings

ASTM B80: Standard Specification for Magnesium-Alloy Sand Castings

Environmental Degradation of Advanced and Traditional Engineering Materials, Lloyd H. Hihara et al., 2014.