Figure 8 Effect of Irradiation on Tensile Properties of 2SO Aluminum

REACTOR USE OF ALUMINUM DOE-HDBK-1017/2-93 Plant Materials Aluminum is attacked by both water and steam at temperatures above about 150°C, but this temperature can be raised by alloying with small percentages of up to 1.0% Fe (iron) and 2.5% Ni (nickel). These alloys are known as aerial alloys. The mechanism of attack is attributed to the reaction Al + 3H₂O Ž Al(OH)₃ +3H⁺ when the hydrogen ions diffuse through the hydroxide layer and, on recombination, disrupt the adhesion of the protective coating. Aluminum-uranium alloys have been used as fuel elements in several research reactors. Enriched uranium is alloyed with 99.7% pure aluminum to form the alloy. Research has shown that radiation produces changes in both annealed and hardened aluminum and its alloys. Yield strength and tensile strength increase with irradiation. Data indicates that yield strengths of annealed alloys are more effected by irradiation than tensile strengths. The yield strengths and the tensile strengths of hardened alloys undergo about the same percent increase as a result of irradiation. Irradiation tends to decrease the ductility of alloys. Stress- strain curves for an irradiated and an unirradiated control specimen are shown in Figure 8. Figure 8 illustrates the effect of neutron irradiation in increasing the yield strength and the tensile strength and in decreasing ductility. Figure 8 Effect of Irradiation on Tensile Properties of 2SO Aluminum MS-05 Page 50 Rev. 0