Nucleation and growth simulations of CuZr phase and comparison with the classic theory

• Grant number: 20/00639-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2020
• End date: July 31, 2021
• Field of knowledge: Engineering - Materials and Metallurgical Engineering
• Principal Investigator: Marcelo Falcão de Oliveira
• Grantee: João Henrique Mazo
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

Metallic glasses are metallic materials that do not present any atomic ordered structure at medium and long ranges. They are special kind of alloys that have brought attention lately due to some interesting mechanical properties that are superior to traditional alloys. In order to increase the fabrication quality and to make it easier and cheaper it is important that nucleation and growth characteristics of these alloys are well known, since the desire is to avoid the occuring of these phenomena during the synthesis or conformation process. The main goal of this project is to calculate important parameters that are related to homogeneous nucleation during solidification, as nucleation rate and growth rate for the CuZr phase (formed by the crystallization at B2 structure of the Zr50Cu50 alloy at high temperatures). The computation of these quantities will be done by two means: the first one indirectly, using classic nucleation theory equations and the simulation only as a mean for obtaining its arguments, the second one in a direct manner obtaining the parameters as a result of counting aided with diverse mathematical/computational tools that allow to identify crystals formed during the simulation, the atoms that make them up and its evolution with time. Thus, it will be possible to compare the results predicted by the classic theory with results obtained directly by simulation, what may contribute with a possible new confirmation of vitreous alloy that follows the classic theory. (AU)