Inverse segregation in Al-Cu alloys

Inverse segregation has been studied in unidirectionally cast ingots as a function of alloy composition and casting conditions. Chill face segregation and the extent of segregation adjacent to the chill face has been examined in the Al-Cu and the Al-Ag systems, using radioactive copper (Cu64) and radioactive silver (Ag110) to measure the segregation. The results indicate that the observed segregation is markedly dependent on the alloy composition, melt superheat, thermal conductivity of the chill, temperature gradient in the casting, and other casting variables. The results obtained are compared to those reported in the literature for the Al-Cu alloys, and to the values predicted theoretically.Science, Faculty ofEarth, Ocean and Atmospheric Sciences, Department ofGraduat