Manufacture of amorphous metal samples by arc melting and casting of alloys based on Nb-Ni

• Grant number: 13/16700-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2013
• End date: July 31, 2015
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Marcelo Falcão de Oliveira
• Grantee: Felipe Henrique Santa Maria
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

The main difficulty to enlarge the use of amorphous metals is to set up processes and compositions that allow the fabrication of metal samples that have significant dimensions. Nowadays many amorphous alloys known are in form of powders or ribbons with thicknesses of nano/micrometer size produced by rapid solidification processes or high-energy milling. This project aims to preferentially produce amorphous metal parts with relevant dimensions (a few millimeters or even centimeters) by an electric arc in an inert atmosphere (necessarily with extreme cleanliness) and cooling in copper molds, refrigerated boosted by vacuum suction. The experimental apparatus was developed in a previous project, FAPESP 2006/00675-4. The system has argon inside the melting chamber and with the help of getters for greater purification of the atmosphere, where they act capturing the oxygen which is released in the melting steps. After melting the alloy the mould is filled by, vacuum suction, the liquid, into which the alloy is cooled and solidified. After solidification, the material will be initially examined by optical microscopy and by the method of X-ray diffraction, subsequently by thermal analysis and measurement of oxygen level in the samples by infrared detection. (AU)