A.8.1. Magnesium-Aluminium-Zinc Alloy

PRODUCT

Type

Metal Alloy

Chemical Composition

8.5% Al, 0.5% Zn, Rem. Mg

Manufacturer

Magnesium Elektron

          PO Box 23, Swinton

          Manchester M27 8DD

          UK

Tel: + 44 (0)161 911 1000

Fax: + 44 (0)161 911 1010

Email:

www.magnesium-elektron.com/

EXPERIENCE & AVAILABILITY

Development Status

Commercial Product

Cost Range

Low

Lot Reproducibility

ASTM AZ80; AZ85, DIN 1729, MgAl8Zn

Space Experience

Good

GENERAL PROPERTIES (Physical, Mechanical, Thermal, Electrical, Optical)

Nature

Typical Value

Remarks

Specific Gravity

1.80

@ Room Temperature

Ultimate Tensile Strength

235 to 330 MPa

@ Room Temperature

Proof Stress (0.2%)

150 to 227 MPa

@ Room Temperature

Elongation at Break

2 to 9%

@ Room Temperature

Thermal Conductivity

90 W m -1 °C -1

@ Room Temperature

Thermal Expansion Coefficient

26 to 27 x 10-6 °C -1

@ Room Temperature

Electrical Resistivity

1.4 x 10-7 W m

@ Room Temperature

PROPERTIES RELEVANT TO SPACE USE

Nature

Typical Value

Type of Test

Corrosion

Has poor resistance to atmospheric corrosion and should always be protected.

 

Stress Corrosion

Is prone to stress corrosion cracking in air, fresh water, sea water and salt solutions. Not suitable for structural applications, see ECSS-Q-70-36.

 

Temperature Range

Maximum application temperature is 150°C.

 

SPECIAL RECOMMENDATIONS

·          The part should be Lanolin covered or oiled at all times during machining and prior to protective treatments so as to avoid corrosion.

·          Protective treatments can be either:

1.        Anodising and painting,

2.        Chromating and painting.

·          The part should never make direct contact with other metals. Magnesium is more electrochemically negative than all other commonly used metals and will therefore be sacrificially corroded in any electrochemical cell that is created.