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ME298-062
Deformation and life modeling in high temperature mechanics-
gas turbine aspects [1 unit]

UC Berkeley, autumn 2014


Contact
Prof. Kjell Simonsson
Div. of Solid Mechanics
Linkoping University
581 83 Linkoping, Sweden
kjell.simonsson@liu.se
tel +46 (0)13 282731
----------------------------------
During the Fall semester, 2014:
Dept. of Mechanical Engineering
6171 Etcheverry Hall, University of California, Berkeley
kjell.simonsson@berkeley.edu
tel (510) 502- 4689


Course syllabus
Course syllabus

Course structure
The course content will consist of 5 major parts, for which the
associated material will be found via the links below.
A code will be needed in order to get access to the files.
The material aims at giving a brief overview of the discussed topics;
for more comprehensive and detailed discussions, the reader is referred to the literature.
In order to make the text somewhat self contained,
some basic/background material will be found in appendices at the end of the documents.
Further references will also be given at the end of the web page.
Each part will be given approximately the same amount of seminar time,
except for the last part which is expected to be given some more time.
The examination will consist of 3 papers, for more details see below


Part 1, Introduction

General information about the course and its examination can be found in the notes for Seminar 1

notes, Seminar 1
notes, Seminar 2


Part 2, Materials for high temperatures; superalloys
notes, Seminar 3
notes, Seminar 4

Examination, Paper 1
Examination, Paper 1
use Times New Roman, 12 pts, line spacing:1.5 lines

Part 3, Basic thermomechanical and numerical framework- 1D-presentation
Dealing with deformation and life modelling- a good knowledge of plasticity is essential!
Dealing with other types of simulations- an understanding of plasticity will often be useful!
We will will here take a first look at it in a 1D-context,
since the full 3D-theory will be form equivalent!
For helping you better understand the theory, and for discussing some specific details,
you will below also find some additional problems (some of them easier than others)
notes, Seminar 5 (ideal plasticity- on whiteboard- no power point pres.)
The last part about hardening will be presented on Sem. 6,
together with a discussion about the numerical handling in Paper 2, see below
notes, Seminar 6, same as for Sem. 5 (hardening- on whiteboard- no power point pres.)
Associated problems NOT mandatory, NOT part of the exam!
-----------------------------------------------------------
Today, many publications in the field of modelling take their basis in thermodynamics,
and it is therefore very useful to have a general idea about
how to thermodynamically handle inelasticity!
We will here restrict our attention to the 1D-context,
since the full 3D-theory will be form equivalent!
As will be seen, our plasticity- and creep models discussed on Seminars 5 and 6,
are consistent with the 2'nd law of thermodynamics :)
For the sake of completeness,
you will below also find some additional problems (discussing issues not proven in the seminar notes)
THIS MATERIAL IS LEFT FOR SELF STUDY!
notes, SELF STUDY
Associated problems NOT mandatory, NOT part of the exam!
-----------------------------------------------------------
The FE-method is the standard tool in Solid Mechanics.
We will here take a look at how to solve non-linear problems in an FE-context.
A simple 1D example, will also be given.
notes, Seminar 7 (on whiteboard- no power point pres.)
(have forgot a [C] on Page 6, you'll see where it is missing :)
Simple 1D example

Examination, Paper 2
Examination, Paper 2
no requirements w.r.t. number of pages
Below some comments regarding the numerical handling can be found
(please note that everything could instead have been done directly w.r.t. the plastic strain,
which would have been somewhat somewhat shorter- doesn't matter,
and don't forget to update the backstress)
Some comments about the numerical handling
IT IS OK WITH A HAND WRITTEN REPORT
(EXCEPT FOR THE GRAPHS AND CODING :)


Part 4, Plasticity and creep
We will here take a quick glance at 3D-plasticty
notes, Seminar 8 (and part of 9), on whiteboard- no power point pres.
Since sometimes an anisotropic plasticity model is needed,
a quick glance of how to model such a behavior will also be given
(more complicated subject, which we don't have time to dig into)
A note on how to model pl. anisotropy
It is of course clear that the level of anisotropy varies from case to case,
where in some cases it is of uttermost importance to model it,
while in some other cases it might be negligible.
For some examples of data for sheet metal applications, see e.g. Larsson and Jansson below,
data for single-crystals, see Leidermark below, and data for SLS/SLM, see e.g.
Lundgren and Patel (unfortunately in Swedish).
Finally, we will take a look at how to model creep
notes, for part of Seminar 10 (on whiteboard- no power point pres.)

Part 5, Fatigue life analysis
A short introduction to High Cycle Fatigue (HCF) and Low cycle Fatigue (LCF)
can be found in the following documents.
HCF, Part I
HCF, Part II
LCF, Part I
LCF, Part II
However, on part of Seminars 10 and 11, a condensed version with only the main ideas will be presented,
with references to high temperature applications where relevant.
MATERIAL FOR PART OF LECTURE 11 AND LECTURE 12, FATIGUE CRACK PROPAGATION
Fatigue crack prop, Part 1
Fatigue crack prop, Part 2

Examination, Paper 3
Examination, Paper 3

Backround material complied for the course
Part 1, Introduction
Part 2, Materials for high temperatures; superalloys


Some references
These texts contain general introductions to gas turbines and nickel base superalloys
and are the sources for most of the pictures and tables found in the rest of the course material.
They will probably provide some input to Paper 1,
as well as providing references to further reading.
Introductional part of dissertation by D.Leidermark
Introductional part of thesis by M.Segersall
Introductional part of dissertation by R.Eriksson
Introductional part of dissertation by D.Gustafsson
Introductional part of thesis by E.Lundstrom
Below can be found some additional references regarding plastic anisotropies:
Introductional part of thesis by R.Larsson
Jansson et al. (2005), On constitutive modeling of aluminum alloys ..., Int. J. of Plasticity, Vol 21, 1041-1058
Lundgren and Patel, BSc-thesis (in Swedish)


Page responsible: Bo Torstenfelt
Last updated: 2014-11-20