Venue: Ferrara, IUSS Turchi di Bagno, Corso Ercole I d'Este, 32 (near Palazzo Dei Diamanti)
The AIAS Ph.D. summer school is held at IUSS - Ferrara 1392. IUSS - Ferrara 1391, is a structure that offers university courses at the undergraduate and graduate level with the highest qualification. It is a center of studies open to italian and international students. From January 2009 IUSS-Ferrara 1391 hosts the Giorgio Bassani Foundation with the aim of promoting the collection, protection, conservation, management and development of documents, as well as the promotion of studies and cultural activities regarding the multiform activities and various interests of the famous writer. Fundamental characteristics of IUSS - Ferrara 1391 are to make the most of talent using only the highest criteria for the selection of students, an international character based on the involvement of international scholars and students, the opportunity to reside in Ferrara with the creation of a Residential College that is a point of reference for the most deserving Italian and international students, besides being tools of cultural mixing. Each year IUSS-Ferrara 1391 invites as Copernicus Visiting Scientists Italian scholars resident abroad and international scholars to stay in Ferrara for at least two months, with the aim of achieving excellent teaching standards at an international level.
Introduction to fatigue
Prof. Laura Vergani
Politecnico di Milano, Italy
The scope of the lecture is to give the basic concept of fatigue life.
The points that will be treated are: Stress-Based Approach to Fatigue; fatigue strength and infinite life; effect of notches and mean stress; Strain-Based Approach to Fatigue, low-cycle fatigue; Life Estimates for Structural Components
Introduction to fatigue
Prof. Paolo Livieri
University of Ferrara
The scope of the lecture is to Review of Complex and Principal States of Stress and Strain for linear elastic materials.
Definition of basic equations for equilibrium and compatibility. Stress and strain components.
Basic solutions for elastic materials: elliptical hole, crack, rounded notch, V-notches.
Multiaxial fatigue assessment of metallic structural components
Prof. Luca Susmel
The University of Sheffield, Sheffield, United Kingdom
The 3-hour lecture begins by reviewing those definitions suitable for calculating those design quantities that are commonly used to perform the fatigue assessment. Pivotal concepts which should always be kept in mind when designing components against fatigue are summarised (mainly considering uniaxial and torsional situations). The multiaxial fatigue assessment problem is then investigated in great detail, by focusing attention on both the high- and the medium-cycle fatigue regime. The MWCM-based procedure suitable for estimating multiaxial fatigue damage both in plain and notched components is explained, with this being done by focusing attention on the most efficient ways to assess fatigue strength by post-processing Finite Element results.
Very-High-Cycle Fatigue of metallic materials: experimental methods and analyses
Prof. Davide S. Paolino
Politecnico di Torino
The lecture is devoted to the Very-High-Cycle Fatigue (VHCF)
characterization of metallic materials.
The following topics will be covered in the lecture:
Experimental methods adopted for investigating the VHCF region;
Specimen design for ultrasonic VHCF tests;
Analysis of typical fish-eye fractures in VHCF;
Relevant theories proposed in the literature for modelling crack
growth in the VHCF region;
Statistical methods for the analysis of the experimental data in the
Size effects in VHCF;
VHCF of conventional and additive manufacturing materials: example
of experimental datasets.”
Numerical and experimental local approaches in Fatigue
Prof. G. Meneghetti
Università di Padova
The notch and crack tip fields with the associated damage mechanisms are steadily under active investigation in situations involving both static and cyclic loading. Combined input from analytical, numerical and experimental approaches are required to improve design methodologies for modelling cracking processes and estimating strength and lifetime of structural components. In this context two contributions are presented, regarding the J-integral and the Notch-Stress Intensity Factor approaches for fatigue lifetime estimations.
An analytical link is known to exist between the J-integral and the strain energy density averaged in a control volume embracing the crack tip. On the other hand, the strain energy fluctuation is the source of temperature variations close to a fatigue crack tip of a metal material; hence the possibility to evaluate experimentally the J-integral from infrared thermographic scanning at the crack tip is envisaged and it is the focus of the first lecture. The second lecture will present a FE-based approach to fatigue analysis of welded structures, which is theoretically supported by the Notch-Stress Intensity Factor description of the local stress fields. An efficient numerical implementation into a commercial FE software package will also be presented.
Prof. A.A. Zadpoor
Delft University of Technology
To be announced
Theory of Critical Distance
To be announced