• Abdulkareem, Omar

Abstract

<jats:p>Shape Memory Alloys (SMAs) are a unique class of material that possesses unconventional properties such as the shape's memory effect, the high flexibility associated with damping capabilities, high wear resistance and fatigue. Given its use in a variety of technological applications, its studies have attracted increased interest in the community of scientists and researchers during the past decades. The shape memory alloy (Cu 83%-Al 13%-Ni 4%) and the other alloy with adding the alloying elements (Mg) with content of (0.25, 0.5, 0.75, 1.0, 1.25) % as a volumetric ratio which was taken from the copper percentage were prepared by powder metallurgy, The powders were mixed using (V-type) powders mixer with mixing speed and time (20 rpm), (16 min) respectively then the samples were pressed by a two-way press (floating die) and pressing pressure (500 MPa) then the green samples where sintered by using vacuum furnace with using Argon gas medium at a temperature (900°C) for one hour and left in the oven to cool down to room temperature. The results showed that both bulk density and apparent density compared to the base alloy increase by increasing the volumetric fraction of Mg by the ratios (5.49)% compared to the bulk density of the base alloy and by the ratios (1.51)% compared to the apparent density of the base alloy. accompanied by a decrease in the real and apparent porosity and water absorption, The results of the mechanical tests showed an increase in the hardness and diametrical compressive strength with the increase of volumetric fraction of (Mg) compared to the base alloy accompanied by a decrease in the rate of wear, The (XRD) test observes the composing phases (α(Cu4Al), β(Cu3Al), γ(Cu9Al44)) in addition to determining the transformation temperature from the Martensite to the Austenite by examining the (DSC) it was found that the Austenite initiation and finish (As), (Af) increased by adding the alloying elements (Mg).</jats:p>

Topics

• density
• phase
• x-ray diffraction
• wear resistance
• strength
• fatigue
• hardness
• copper
• differential scanning calorimetry
• porosity