Residual stress evaluation in aluminum alloys joined by Friction Stir Welding using ultrasonic waves.

• Grant number: 18/18546-3
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2019
• End date: July 31, 2021
• Field of knowledge: Engineering - Mechanical Engineering - Mechanics of Solids
• Principal Investigator: Auteliano Antunes dos Santos Junior
• Grantee: Auteliano Antunes dos Santos Junior
• Host Institution: Faculdade de Engenharia Mecânica (FEM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Aluminum alloys have been widely used in the manufacture of structural components that require low weight and moderately high mechanical strength. However, processes involving heat such as conventional welding can affect the properties of these alloys. The Friction Stir Welding (FSW) is a solid state welding process which has proved to be an alternative to weld materials that were once classified as non-weldable by conventional methods, such as 2XXX and 7XXX aluminum alloys. Among the ways of evaluating the quality of joints welded by FSW, measuring the magnitude and distribution of residual stresses stands out because it is necessary that the structures are not distorted and don't have internal stresses that can lead to failures in service. There are several destructive and non-destructive methods for residual stresses determination, but the non-destructive methods keep driving more attention of the industry due to their feasibility and to the fact that they don't influence permanently the element under inspection, reducing costs. This proposal aims to develop a method for measuring residual stresses on high strength aluminum plates joined by FSW using ultrasonic waves, therefore using its results as an indicator of welding quality, allowing the optimization of the process. The stress measurement using the ultrasonic method is based on the acoustoelastic effect that relates the variation of the ultrasonic wave velocity with the change of the stress levels within the material. As a result of this project, the development of a doctoral thesis, two master's dissertations, and an undergraduate scientific initiation are also expected (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

GONCALVES, V. V.; DOS SANTOS JUNIOR, A. A.. Effect of Non-uniformity on Time-of-Flight Measurement of Critically Refracted Longitudinal Waves for Stress Evaluations of Carbon Composite Materials. EXPERIMENTAL TECHNIQUES, v. 46, n. 1, p. 1-15, FEB 2022. (18/18546-3, 13/21616-0)

RUANO, SHIRLEY ALEXANDRA GARCIA; DOS SANTOS JUNIOR, AUTELIANO ANTUNES. Quality index for friction stir welds in 7050 aluminum plates. MATERIALS & DESIGN, v. 222, p. 10-pg., 2022-08-27. (18/18546-3)

GARCIA RUANO, SHIRLEY ALEXANDRA; DELIJAICOV, SERGIO; DOS SANTOS JUNIOR, AUTELIANO ANTUNES. Acoustoelasticity to measure residual stresses in plates of 5052 aluminum joined by FSW. Journal of the Brazilian Society of Mechanical Sciences and Engineering, v. 45, n. 2, p. 13-pg., 2023-02-01. (18/18546-3)