# QE22A (QE22A-T6, 3.5106, M18220) Magnesium

QE22A magnesium is a magnesium alloy. Cited properties are appropriate for the T6 temper. To achieve this temper, the metal is solution heat-treated and artificially aged until it meets standard mechanical property requirements. QE22A is the ASTM designation for this material. M18220 is the UNS number.

It has a very high density among magnesium alloys. In addition, it has a fairly high melting temperature and a fairly high embodied energy.

The graph bars on the material properties cards below compare QE22A magnesium to other magnesium alloys (top) and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.

## Mechanical Properties

Brinell Hardness

80

Compressive (Crushing) Strength

350 *MPa* 50 *x 10 ^{3} psi*

Elastic (Young's, Tensile) Modulus

44 *GPa* 6.4 *x 10 ^{6} psi*

Elongation at Break

2.4 *%*

Fatigue Strength

110 *MPa* 15 *x 10 ^{3} psi*

Fracture Toughness

15 *MPa-m ^{1/2}* 14

*x 10*

^{3}psi-in^{1/2}Poisson's Ratio

0.29

Shear Modulus

17 *GPa* 2.5 *x 10 ^{6} psi*

Shear Strength

150 *MPa* 22 *x 10 ^{3} psi*

Tensile Strength: Ultimate (UTS)

250 *MPa* 37 *x 10 ^{3} psi*

Tensile Strength: Yield (Proof)

190 *MPa* 27 *x 10 ^{3} psi*

## Thermal Properties

Latent Heat of Fusion

340 *J/g*

Maximum Temperature: Mechanical

250 *°C* 480 *°F*

Melting Completion (Liquidus)

640 *°C* 1190 *°F*

Melting Onset (Solidus)

570 *°C* 1060 *°F*

Solidification (Pattern Maker's) Shrinkage

1.3 *%*

Specific Heat Capacity

970 *J/kg-K* 0.23 *BTU/lb-°F*

Thermal Conductivity

110 *W/m-K* 65 *BTU/h-ft-°F*

Thermal Expansion

27 *µm/m-K*

## Electrical Properties

Electrical Conductivity: Equal Volume

25 *% IACS*

Electrical Conductivity: Equal Weight (Specific)

120 *% IACS*

## Otherwise Unclassified Properties

Density

2.0 *g/cm ^{3}* 120

*lb/ft*

^{3}Embodied Carbon

27 *kg CO _{2}/kg material*

Embodied Energy

220 *MJ/kg* 95 *x 10 ^{3} BTU/lb*

## Common Calculations

Resilience: Ultimate (Unit Rupture Work)

5.5 *MJ/m ^{3}*

Resilience: Unit (Modulus of Resilience)

400 *kJ/m ^{3}*

Stiffness to Weight: Axial

13 *points*

Stiffness to Weight: Bending

60 *points*

Strength to Weight: Axial

36 *points*

Strength to Weight: Bending

46 *points*

Thermal Diffusivity

59 *mm ^{2}/s*

Thermal Shock Resistance

15 *points*

## Alloy Composition

Mg | 93.1 to 95.8 | |

Ag | 2.0 to 3.0 | |

Zr | 0.4 to 1.0 | |

Cu | 0 to 0.1 | |

Ni | 0 to 0.010 | |

rare e. | 1.8 to 2.5 | |

res. | 0 to 0.3 |

All values are % weight. Ranges represent what is permitted under applicable standards.

## Followup Questions

## Similar Alloys

## Further Reading

Magnesium Alloys Containing Rare Earth Metals: Structure and Properties, L.L. Rokhlin, 2003

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

ASTM B403: Standard Specification for Magnesium-Alloy Investment Castings

Welding and Joining of Magnesium Alloys, Liming Liu (editor), 2010

ASTM B80: Standard Specification for Magnesium-Alloy Sand Castings

Essential Readings in Magnesium Technology, Suveen N. Mathaudhu et al. (editors), 2014

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