Semisolid state processing of new Al-Ti-(Zn-Cu-Mg) materials. Mechanical properties, resistance to wear and corrosion

• Grant number: 23/09182-6
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• Start date: February 01, 2024
• End date: January 31, 2025
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Eugênio José Zoqui
• Grantee: Eugênio José Zoqui
• Visiting researcher: Hipolito Domingo Carvajal Fals
• Visiting researcher institution: Universidad de Oriente, Cuba
• Host Institution: Faculdade de Engenharia Mecânica (FEM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

In this research project we intend to study the processing in the semisolid state of new materials (Al-Ti-(Zn-Cu-Mg), as well as the mechanical properties, resistance to wear and corrosion. The alloys designed with the aid of computational tools (Calphad) will be obtained in resistive electric furnaces of 9.6 and 12kW of power. Later they will be processed in the semi-solid state via: Recasting using the GISS technique, (Gas Induced Semi-Solid), and, for the Thixoforming the EMS technique (Electromagnetic Stirring). The rheological characterization will be carried out via a Searle-type rheometer for high temperatures. The alloys will be injected into a Delta T40 pressure injection machine (acquired in a project Process Fapesp 2018/11802-4), after preparing the semisolid slurry. The mechanical properties (hardness and tensile strength) will be determined and the microstructural characterization performed through metallographic tests (optical and scanning electron microscopy) and X-ray diffraction (DRX). Residual porosity, average grain size and the presence and morphology of micro precipitates will be determined. The coefficient of friction of the alloys before and after processing in a semi-solid state will be evaluated using pin-on-disk tests on polished samples using an alumina sphere as counterpart with a diameter of 6 mm, 10 cm/s of linear and speed with a normal force of 10 N. Corrosion tests will be carried out using the technique of potentiodynamic polarization and impedance measurements, following ASTM G59-97 and G102-89 standards. Samples with a surface area of 1.0 cm2 before and after processing will be selected and evaluated in a 3.5 wt% NaCl solution. (AU)