Impact of rare earth elements Ce and Pr addition on grain refinement of AA5083 alloy

Abstract

One of the most common methods for grain refinement (grain size reduction) is the addition of a specific alloying element (as grain refiner). Through grain refinement, it is possible to obtain significant improvement in the specific properties of materials. The grain refinement is obtained by changing the size of a grain structure. Thus the measurement of grain size is the indicator of performance for grain refinement. In this work, the rare earth elements REEs ( REEs = Ce and Pr ) with five different mass percentages (0.1 %, 0.3 %, 0.5 %, 0.7 %, and 1.0 %) of Ce and Pr, were added to the AA5083 alloy to estimate the grain size of modified AA5083 alloys as a function of type and percentage of REEs additives. The average grain size was estimated by two methods; by intercept method according to the ASTM E 112 standard, and by image processing technique using Image J software. It was found that the type and percentage of content of rare earth element Ce and Pr additives play a role in controlling grain refining efficiency. It was also found that the estimation of the grain size by the image processing technique by using image J software gave satisfactory results compared with the results obtained by the intercept method. Thus we can consider the image j software to have a high efficiency for estimation of the grain size.