Relaxation dynamics of Fe55Cr10Mo14C15B6 metallic glass explored by mechanical spectroscopy and calorimetry measurements

• DOI: 10.1007/s10973-016-5379-9
• Publication Date: 2016-03-18T11:16:02Z
• Authors: Chaoren Liu; Milad Madinehei; Eloi Pineda; Daniel Crespo
• Keywords: Àrees temàtiques de la UPC::Enginyeria dels materials; Viscosity; Physical aging; Metallic glasses -- Viscosity; Mechanical relaxation; :Enginyeria dels materials [Àrees temàtiques de la UPC]; 01 natural sciences; Vidres metàl·lics; Metallic glass; 0103 physical sciences; Metallic glasses; Structural relaxation; Anelastic

In this work, the mechanical relaxation dynamics of Fe55Cr10Mo14C15B6 metallic glass is explored by mechanical spectroscopy. The temperature-dependent loss modulus E″(T) shows the features of β relaxation well below glass transition temperature Tg. This β relaxation can be well described in the framework of anelastic theory by a thermal activated process with activation energy of 165 kJ mol−1. Structural relaxation, also known as physical aging, has a large effect on the glass properties. The activation energy spectrum of structural relaxation is characterized by differential scanning calorimetry measuring the heat flow difference between as-quenched and relaxed states. The obtained energy spectrum is well described by a lognormal distribution with maximum probability activation energy of 176 kJ mol−1. The obtained activation energy of structural relaxation is similar to that of β relaxation observed from mechanical spectroscopy. Both values are also close to the Johari–Goldstein β relaxation estimated by the empirical rule Eβ = 26RTg.<br/>Peer Reviewed<br/>