In situ detection of two-stage crystallization in ZrTiCuNiBe under high pressure and high temperature

Abstract

Structural changes in bulk metallic Zr41.2Ti13.8Cu12.5Ni10Be22.5 glass subjected to heat treatments under high pressure were investigated by means of synchrotron radiation x-ray diffraction (SRXRD). In situ SRXRD measurements showed that the crystallization process of this material is comprised of two stages. Subsequent heating at 10 GPa converts the sample from the amorphous (Am) phase into a metastable fcc phase and then leads to the fcc phase changing back to the Am phase, indicating that there is a kind of ‘reversible’ phase transition phenomenon occurring in the alloy. Such phenomenon is explained on the basis of free energy considerations.

Pressure effect on crystallization of Zr41Ti14Cu12.5Ni10Be22.5bulk metallic glass prepared by shock-wave quenching

“…For the new materials family of Zr 41 Ti 14 Cu 12.5 Ni 10 Be 22.5 bulk metallic glass (BMG), which are of high thermal stability and have great potential for engineering applications, the phase transition, or crystallization process, under static high pressure can pass through different sequences [4][5][6][7][8][9][10]. In addition to the crystallization sequence, or phase precipitation sequences, the phase precipitation onset temperature, or crystallization temperature (T x ), during crystallization of the BMG may even be further influenced by pressure.…”

“…In this case, T x increases greatly with pressure, while the crystallization sequence is the same for different pressures. The influence of pressure on the crystallization sequence has also been proved experimentally [7,9]. In a such case, pressure can change both the crystallization sequence and T x , because changed crystallization sequences (different initially precipitated phases) can cause a decrease in T x .…”