Effect of Alloying Elements and Heat Treatment on Behavior of the Alloy (Cu,Al) Used in Marine Industries

Abstract

The research deals with using powder metallurgy in atmospheric vacuum to prepare samples with (Cu-9.5Al). The silicon and nickel elements are added with (3wt%) and (5wt%) to (Cu-9.5Al)based respectively. Also (3wt%Si,5wt%Ni,1wt%Mn,4wt%Fe) elements are added to alloy based.Several tests were carried out ,such as Green, final porosity ,densities, compression, wear with (Pin-on-Disk)- type ,hardness. Corrosion tests, which include the simple immersion method and corrosion /erosion. The study indicated the increase in weight loss for corrosion/erosion test with phase transformation before and after heat treatment. The results indicate that the added alloy elements to the alloy based increase in corrosion resistance about (113.3 – 566.6%). Also high resistance in corrosion/erosion of two alloys are calculated. When the heat treatment are carried out, the improvement ratio is (488.9%),and the hardness has (185HV) value. The compression strength and ductility have improved with excellent value. The mechanical wear resistance have low change after heat treatment. While, the addition of (Si) and all the above mentioned metals to the base alloy, increase the resistance to wear and give the lowest corrosion The change case in weight with time indicate a stable case after exposed to corrosion media. The addition of (Si) metal with (3wt%) gave higher value in resistance to sliding wear and follow in (Fe) metal in the same behavior, where the improvement ratio, are (165%) and (126%). Alloy (Cu-Al-Ni-Mn-Fe-Si) also demonstrates a high hardness, low corrosion rate in sea water, good resistance to wear and compressive strain. These improvements were attributed to enhancement of properties of alloy based (Cu – 9.5 Al) used in Marine propellers industry.