Processing of Ni-based metallic glass ribbons by melt spinning

• Grant number: 15/03168-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2015
• End date: April 30, 2016
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Piter Gargarella
• Grantee: Otávio Henrique Borges
• 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

Abstract

Glassy metals have unique properties compared to conventional crystalline metals as mechanical strength close to theoretical limits, excellent corrosion resistance and ease conformability in the supercooled liquid state. They have several applications as wear and corrosion resistant coatings, in transformers, as miniature engine parts, pressure sensors, sporting goods and electronics parts. New applications are being investigated such as bipolar plates used in proton exchange membrane fuel cells (PEMFC). Many of these applications use thin glassy ribbons or sheets and a good superficial quality is vital for the application, especially concerning mechanical and corrosion resistance. This makes important to investigate the effect of different processing parameters on the quality of the ribbons and sheets produced. A method already established for the production of glassy ribbons is the melt spinning technique. By this technique, ribbons with width about 3 to 4 mm and a thickness of 40 microns are generally obtained. This technique can also be used for the production of wider ribbons using special crucibles during melting. This project aims to produce Ni57Nb33Zr5Co5 glassy ribbons (15 mm wide) by Melt Spinning. The influence of various processing parameters (processing temperature, rotational speed of the Cu wheel, distance between the wheel and crucible, injection pressure, etc.) on the quality of the strips should be investigated. Ingots of this alloy will be produced in electric arc furnace and metal strips will be fabricated by the Melt Spinning technique. The strips will be characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM).