C18661 Copper-Magnesium (CMG1) Alloy Wire

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Copper-magnesium is a solid solution alloy providing high strength with nominal reduction in conductivity relative to copper. CMG1 is one of the alloys covered by the broad CDA alloy designation C18661 for copper-magnesium. CMG1 combines high electrical conductivity with good tensile strength, excellent solderability and plateability. Applications include connectors, semiconductor pins, catenary trolley cables and conductors. There are no ASTM developed temper ranges for this alloy and the listed values are the recommendations of Fisk Alloy Wire.

Mechanical Properties

Round Wire

Temper Name  Temper Code  Tensile Strength (ksi)  Mill Limits 
Min Max
Annealed   35 46 .0010 - .1285 inch
1/2 Hard H02 55 70
Hard H04 75 90
Spring H08 90  

Square Wire

Temper Name  Temper Code  Tensile Strength (ksi) Mill Limits 
Min Max
Annealed   35 46 .0100 - .0808 inch
1/2 Hard H02 55 70
Hard H04 75 90
Spring H08 90  

Physical Properties

Melting Point (Liquidis) 1958°F
Melting Point (Solidus) 1850°F
Density 0.321 lbs/cu in
Electrical Resistivity (Annealed) 14.1 ?(cir mil/ft) @ 68°F
Electrical Conductivity (Annealed) 74% IACS @ 68°F
Coefficient of Thermal Expansion 0.0000098°F (68-572°F)
Modulus of Elasticity (Tension) 18125 ksi