Reactive milling and hydrogen storage properties of high entropy alloys of the Mg-Ti-Zr-V-Fe-Co-Ni system

• Grant number: 17/16273-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2017
• End date: January 31, 2020
• Field of knowledge: Engineering - Materials and Metallurgical Engineering
• Principal Investigator: Guilherme Zepon
• Grantee: Vinícius Aranda
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 13/05987-8 - Processing and characterization of amorphous, metastable and nano-structured metallic alloys, AP.TEM
• Associated scholarship(s): 18/25154-4 - Hydrogen storage properties of the MgTiVZrFe high entropy alloy, BE.EP.IC

Abstract

A major problem energy-related is waste due to lack of efficient and rapid solutions for its storage. For example, the energy produced for hydropower turbines, wind turbines and solar panels are not efficiently storage at moments in high consumption. The hydrogen is an promising energetic vector that allows the use energy in a sustainable and renewable way, however, the hydrogen storage security and efficient way is a scientific and technological challenge to be overcome. At context, the metals hydrides (MHx) are promising candidates to store large amounts of hydrogen. It has recently been reported that the High Entropy Alloy (HEA) TiZrHfNbV has a large capacity of hydrogen storage, at 2.5 %wt., which is equivalent to an H/M ratio of 2.5, higher than conventional metals hydrides. Recently, our research group showed that the MgTiZrFe0,5Co0,5Ni0,5 HEA also has interesting storage hydrogen properties, with absorption capacity of about 1.25 %wt. of hydrogen and with fast kinetic of absorption/desorption. Based on this, it is proposed the study of four new composition of HEA of the Mg-Zr-Ti-V-Fe-Co-Ni produced by reactive milling under hydrogen pressure. The alloys produced will be characterized by X-rays diffraction and scanning electron microscopy to evaluate the formed phases and the hydrogen storage properties will be evaluated by differential scanning calorimetry, mass spectroscopy and thermogravimetric analysis. (AU)