Comparison of baseline method and DSC measurement for determining phase fractions

Abstract

By comparing phase fractions upon solidification of Ni-3?3 wt-%B alloy obtained by differential scanning calorimetry (DSC) measurement, microstructure observation and the baseline method, the results show that although as an approximate approach, the baseline method can be used to predict the phase fractions from the cooling curve, and it can reflect the relationship between the transformed fraction, time and temperature simultaneously during solidification, which cannot be obtained from DSC measurement. In addition, the effects of non-constant specific heat and latent heat of phases on the baseline method are discussed and the calibration relationships are deduced.

Latent Heat Determination From Cooling Curves During Solidification of Metals by an Alternative Method Considering the Metal and Mold Cooling Processes

“…For that reason there has been interest in finding new ways of analyzing the cooling curves of metals and alloys during their solidification, giving rise to what are known as Computer Aided Cooling Curve Analysis (CA-CCA), historically represented by the Newton thermal analysis (NTA) [2,3] and the Fourier thermal analysis (FTA) [4].The importance of these methods lies in its ability to generate key information that makes it possible to understand, control and simulate through specialized software, various aspects of solidification and phase transformations in the solid state, of metals and alloys under specific process conditions. In recent years there have been a new generation of methods enhancing and ameliorating the potential applications of CA-CCA [5][6][7][8]. A very relevant change occurred with the proposal of Gibbs and Mendez [5] who, for the first time created a method of quantitative characterization of solidification that did not depend on a zero reference curve but, was based on an energy conservation equation, opening a new avenue for the development of new CCA methods.…”