Production of coating by laser Cladding of quasicrystalline Al-Co-Fe-Cr Alloy

• Grant number: 14/18648-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2014
• End date: July 31, 2015
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Conrado Ramos Moreira Afonso
• Grantee: Laura Galvão Barbosa de Oliveira
• 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

Nanocrystalline alloys and aluminum-based quasicrystalline possess excellent chemical and physical properties such as mechanical strength and corrosion, superior to their crystalline. Through high cooling rates of the alloys from the liquid state is possible to interrupt the process of nucleation of atoms, which thus position themselves in a disorderly way, obtaining nanocrystalline and/or quasicrystalline alloys. The alloy chosen for this study is a Al-Co-Fe-Cr, specifically Al71Co13Fe8Cr8 alloy (at%). The ingots were obtained by arc furnace and processed through rapid solidification by Spray Forming, generating a deposit of millimeters thick and an overspray powder of particle size ranges of <20 µm, 20 to 50 µm, 50-105 µm, 105 180 µm, 180-425 µm and> 425 µm. From the microstructural characterization of these powders and deposits specific particle sizes will be selected to serve as the base (powder) to conduct experiments of Laser Cladding on a substrate of Mild Steel 1020, in 10 x 10 cm and 6 mm thick. The objective of this study is the production of coatings from quasicrystalline Al-Co-Fe-Cr alloys through surface laser treatment (cladding and laser surface remelting) and microstructural characterization of these coatings. In the case of surface remelting, laser remelting of the surface and to the characterization of the remelted base material (Al-based rapidly solidified alloy layer) it will be evaluated the feasibility of obtaining a nanocrystalline or quasicrystalline surface layer with increased hardness. Laser cladding of the powder of Al-Co-Fe-Cr alloy produced by gas atomization for coating a substrate of 1020 Mild Steel, which is going to be characterized in the interface generated between the coating and the mild steel substrate.