Tensile Properties at Very Low Temperature in Aluminum Magnesium Alloys

Tensile strength, ductility, serrated deformation, work-hardening, cracking within the large intermetallic particles and intergranular cracking during straining in the temperature range 4 to 70 K have been mainly investigated. The experiments were performed with polycrystals of 5083–0 aluminum alloy, Al-5.3% Mg alloy and pure aluminum (99.99%). A helium gas flow cryostat and cooling system were used for tension test at the various temperature. Decrease in ductility and cessation of increase in the tensile strength with decreasing temperature were observed in the temperature range 4 to 20 K for 5083–0 aluminum alloy and 7 to 35 K for Al-5.3% Mg alloy. Non uniform deformation corresponding to the serrated flows which were accompanied by heat generations is a main cause for the decrease in ductility, and cracking of the intermetallic particles in 5083–0 aluminum alloy and intergranular cracking in Al-5.3% Mg alloy might be possible causes.