Solid fraction determination via DSC analysis

The solid fraction trend as a function of temperature, Fs(T), is an important parameter in different sectors of metallurgy: from the study of the rheological behaviour of alloys to the simulation of foundry processes as well as in the semi-solid forming techniques. The thermal analysis, in particular the differential calorimetric one (DSC), can represent an optimal tool for measuring the actual solid fraction of an alloy. As known DSC results depend on the used test parameters (sample mass and heating rate), on the calorimetric tracings and on the peaks interpretation. The aim of the present work is the identification of test conditions that allow to better estimate the solidification phenomenon thus to make the DSC analysis a reliable tool for the Fs(T) definition. The A356 aluminium alloy was used for the DSC analyses. The experimental data obtained, varying the heating rate and the sample mass, were compared to those calculated by simulation obtained using CompuTherm Database® and Pandat® software.