Experimental Determination of Rheological Behavior

Abstract

This chapter will be divided into two main parts. The behavior of alloys during partial solidification will be considered first but only alloys with a globular morphology will be examined. In this case, the alloy is considered as a homogeneous medium and therefore, the viscosity only (and sometimes the fluidity) has been determined. Alloys during partial remelting will thereafter be considered. In this case, the solid fraction can vary in large proportions so that the two approaches mentioned above will be detailed. In each part, the experimental methods will be examined first and then, the experimental results will be presented. It is necessary to mention here that only the most representative results will be presented and not all of the results in the literature. In addition to these two main parts, a comparison between partially solidified and partially remelted alloys will be performed. This comparison is important in view of the latest industrial developments of the rheocasting processes. Finally, the question of yield stress will be addressed.