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Go to Editorial ManagerIn this study a Nickel-Titanium-Cupper shape memory alloys was manufactured by powder metallurgy (PM) technique, powder mixture of 50% Ti , 47% Ni and 3% Cu was prepared by mixing for two hours and compacted in a press machine using various compacting pressure (600, 700 and 800) MPa , sample was then sintered for 5 hrs in an electrical tube vacuum furnace using sintering temperature of (850?C, 900?C and 950?C) .phase analysis of samples was conducted by X-ray diffraction test, the effect of different sintering temperature and compacting pressure on the porosity, microhardness ,compression strength and the shape memory effect (SME) was studied, the result showed decrease in the porosity and increasing in the shape recovery ,compression strength and microhardness with increasing compacting pressure and at lower sintering temperature and hence the best results was at 800MPa compacting pressure and 850?C sintering temperature.
This study aims to enhance the compression strength in one type of Pb-Sn-Sb alloys which wellknown by (Babbitt-ASTM B23 Alloy 13). The ?processing doing via equal channel angular extrusion technique. Three casting were implemented to ?manufacture the alloy; Chill Casting (CC), New Rheocasting (NRC) and Gravity Die Casting (GDC). The ?microscope examination shows that the microstructures contain two phases, ?-Pb and cubic shaped ?intermetallic compound (?-SbSn) in a matrix of ternary phases. CC was fine equiaxed as well as NRC, while ?in GDC was a dendrite ?-Pb phase with remaining ?-SbSn phase as a cubic shape. Higher mechanical properties in compression were recorded for Gravity die casting (12.7 %) while the NRC registered the highest value in yield strength (11.7 %). On the other hand, the casting techniques had a slight difference in Young's modulus. The other resulted data like hardness showed that NRC is the first reading (12.55 %) and then gravity casting recorded as second score comparing with other (11.79 %), The results ?showed aslo that increasing forming temperature during angular extrusion has an adverse effect on compression ?strength. The study ?concluded that microstructural change caused by ECAP softens the material due to the break-up the original ? precipitate and accelerate from the dynamic recrystallization.