Manufacturing And Properties Studying Of Cu-Al-Ni Shape Memory Alloys

In this book, shape memory alloys made from Cu Al Ni have been prepared using powder metallurgy technique with 13%wt Al and 4%wt nickel which is the master alloy , having different alloying elements such as Cr, Nb and Ta in ( 0.3,0.6 and 0.9%wt ) additions . After mixing of powders , Disc samples with 14mm diameter and 5 mm thickness as well as cylindrical samples with 11mm diameter and 16.5mm length have been prepared at 650 MPa as suitable compacting stress according to porosity and apparent density results. Sintering in vacuum tube furnace for all prepared specimen has been achieved using two stage sintering temperature 500ºC for one hour and the second in 850ºC for five hours. Physical and mechanical tests have been done after sintering which covered apparent density and porosity, X-ray diffraction and hardness, compression strength ,dry sliding wear and shape effect. Microstructure characteristics were also observed with optical microscope and scanning electron microscope with Energy Dispersive X-ray Spectrometry (EDX).Finally Differential scanning calorimeter (DSC) was used to determine phase transformation temperature for all alloys with additive .