Fatigue Crack Growth curves analysis and life predictions under variable amplitude loading from numeric models to 7475-t7351 al alloy.

• Grant number: 10/11425-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2010
• End date: August 31, 2011
• Field of knowledge: Engineering - Aerospace Engineering
• Principal Investigator: Cassius Olivio Figueiredo Terra Ruchert
• Grantee: Artur Valadares de Freitas Santos
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

The aim of this project is to compare the experimental results previously obtained by Ruchert, 2007 with a numerical model proposed to describe the crack growth curve under variable amplitude loading and verify the adjustment parameters of the model for the loading spectrum used. After the comparison shall be possible optimize the parameters of the numerical model and, consequentially, obtain more precise results of life in fatigue under variable amplitude loading. To develop a model able to describe the crack growth under variable amplitude loading will be used the programs CRACK 2000, AFGROW and GENESIS, this last one is a generator of loading spectra as Twist, Falstaff and their minis, and the flight used in "full-scale" tests by Embraer.The expected result is to be able to formulate models in the programs AFGROW and CRACK 2000 to previse, more precisely, the crack growth curves and the life in fatigue of 7475-T7351 al alloy under variable amplitude loading for random flight stories as Twist, Falstaff and the Embraer flight history used in "full-scale" structural integrity tests.