Consolidation and properties of porous Cu-Al-Ni shape memory alloys manufactured by powder metallurgy

A.P. GÓMEZ; G. URRETAVIZCAYA; A. BARUJ; M.T. MALACHEVSKY

POWDER METALLURGY

MANEY PUBLISHING

Lugar: London; Año: 2023 vol. 66 p. 548 - 556

0032-5899

A method to manufacture a porous Cu-Al-Ni shape memory alloy by powder metallurgyusing space holders is presented. Two aluminium powders with differentparticle morphologies were employed to investigate their influence on phase formation,microstructure and mechanical properties. The variation of the relative amountof space holders in the mixture allows to obtain specimens with different porosities.Samples prepared with irregular shaped aluminium powder include both 18R and 2Hmartensitic phases and exhibit the shape memory effect and pseudoelastic behaviorunder uniaxial compression tests. In contrast, the samples made with aluminiumflakes present the α phase accompanying the 18R martensitic phase, and do not exhibitthe shape memory effect. Both the aluminium flakes flat shape and the higherproportion of aluminium oxide associated to its larger surface area to volume ratiohindered the interdiffusion of the metals, resulting in an aluminium depletedmartensitic phase surrounded by an aluminium oxide rich layered structure.