Comparison of damping measurement and differential scanning calorimetry as methods of determining the glass transition temperature in metallic glasses

Abstract

Low frequency internal friction and differential scanning calorimetry (DSC) measurements were used to determine the glass transition temperature T g of Pd 40Ni 40P 20 and Ni 60Pd 20P 20 over a large range of heating rates Ṫ from 0.025 to 100 K min −1. For the higher heating rates the DSC data were analysed applying different definitions of T g and compared with the internal friction values at lower heating rates. The best agreement between the two sets of data was obtained when T g was defined at the end of the C p increase for as-quenched samples and at the C p peak for relaxed samples. In this case a linear dependence of T g vs. log Ṫ was observed over the whole range of heating rates investigated. The relevance of these results for the experimental determination of T g in general is discussed.