Characterization of cold spray coatings of a quasicrystal-forming Al-Fe-Cr-Ti alloy

• Grant number: 21/10651-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2021
• End date: November 30, 2022
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Piter Gargarella
• Grantee: Felipe Biasi do Monte Carmelo
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 17/27031-4 - Effect of process parameters on the metallurgical characteristics of additive-manufactured alloys, AP.JP

Abstract

Aluminum quasicrystalline (QC) phase forming alloys are known for their high mechanical and wear resistance along with low friction coefficient. These properties make them promising for structural applications in the automotive, aeronautics, and petrochemical industry. However, the QC phase formation requires high cooling rates, which are achieved in the atomization and melting spinning process. Hence, it is common to obtain quasicrystalline alloys in powder and ribbons form, being crucial a secondary consolidation process to produce large parts. This second step is a challenge, mainly for metastable quasicrystalline alloys, once they can decompose during the processing. The cold spray (CS) manufacturing technology can produce coatings with different thicknesses, without being required to melt the sprayed material. By CS, the microstructure of the sprayed material is maintained, as a result, the properties of the material are maintained on the produced coating. Even though the cold spray is a promising technique for quasicrystalline alloys, so far, no studies related to this have been done for Al-Fe-Cr-Ti alloys. Therefore, the present project aims to process the Al93Fe3Cr2Ti2 alloy by cold spray and identify the processing conditions that result in coatings with good characteristics, such as low porosity, high density, high adhesion between layers and substrate, lack of cracks, and inclusions, and high hardness. Analyses of optical microscopy (OM), scanning electron microscopy (SEM), and Vickers microhardness tests will be carried out along the cross-section of the coatings. The porosity and density of the coatings will be measured, as well as the presence of defects, inclusions, and poor adhesion. Moreover, the microstructure will be analyzed by x-ray diffractometer (XRD), differential scanning calorimetry (DSC), and chemical analysis by energy-dispersive X-ray spectroscopy (EDS). (AU)