Fatigue crack closure evaluation of 2050 - T84 aluminum alloy under constant amplitude loading and single overload

• Grant number: 14/18571-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2014
• End date: November 30, 2015
• Field of knowledge: Engineering - Aerospace Engineering
• Principal Investigator: Cassius Olivio Figueiredo Terra Ruchert
• Grantee: Carolina Soares
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

In 1970, Elber introduced the crack closure mechanism and stress intensity factor variation modified concept and the correlation of these parameters with different values of loading rate under fatigue crack growth. The research are motivated to show how is possible to determined the closure and open load and how this values influence the retardation and acceleration present on fatigue crack growth. The methodology for determination of these loads was proposed by ASTM E647 and other authors by modification of ASTM E647. The main aim of this research is related to study of metallic materials fatigue, which evaluates the crack closure effects on fatigue crack growth under variables loading by tests and finite element method. The aluminum alloy 2050 T84 will be used to fatigue crack growth tests under constant and single loading. The crack closure and crack growth measurements will be executed by strain gauges and the clip gauge, respectively. Expected to determine the crack closure under the loads proposed and develop a methodology to determine the crack closure values by finite elements under these conditions.