INSTRUCTION

PROFESSOR K. KOMVOPOULOS

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Mechanical Behavior of Engineering Materials (ME108)

(undergraduate course, junior/senior level)

 

 

Content

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Introduction

Microstructure and Deformation of Materials

Alloying and Hardening

Heat Treatment

Slip Planes, Dislocations, Twinning

Introduction to Mechanical Testing

Stress and Strain

Complex Stress/Strain States

Special topics on Complex Stress States

Yielding and Fracture Criteria

Plastic Deformation

Ductile and Brittle Fracture

Fracture Mechanics

Fatigue, Stress-based Approach

Fatigue, Strain-based Approach

Cumulative Fatigue Damage

Notch Effects in Fatigue

Crack Growth

Time-dependent Deformation, Creep

Friction and Wear of Materials

Micromechanics

Labs

(1) Heat treatment, Phase diagrams, Metallography, Hardness                  

(2) Deformation due to Monotonic Loading

(3) Time- and Rate-dependent Deformation

(4) Deformation due to Cyclic Loading               

(5) Fracture toughness

(6) Fatigue

(7) Wear

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Mechanical Behavior of Engineering Materials (ME224)

(graduate course)

 

 

Content

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 Introduction

  Stress/Strain, Deformation

  Theoretical Strength of Solids

  Elastic Behavior (linear, rubber-like, viscous, iso-/anisotropic)

  Inelastic Behavior

  Principal Stresses/Stress Invariants

  Spherical and Deviatoric Components of Stress Tensor

  Stress Space

  Linear-Elastic Stress-Strain Relationships

  Mechanistic Models

  Yield Criteria, Yield Surface

  Incremental Plasticity (Flow Rule and Strain Hardening Rule)

  Isotropic Hardening

  Fatigue (Stress Concentration, Notch Sensitivity, Endurance Limit)

  Failure Criteria

  High-/Low-Cycle Fatigue

  Strain-Life Approach

  Stress-Life Approach

  Notches, Neuber’s Rule

  Cumulative Fatigue Damage

  Crack Initiation

  Crack Propagation

  Fatigue, Life Predictions

  Fracture (mechanisms, modes, and toughness)

  High-Temperature Deformation, Mechanisms

  Creep Resistance, Creep Deformation Maps

  Dislocations, Types and Properties

  Moving Dislocations and Interactions

  Strengthening Mechanisms      

  Contact Fatigue

  Wear, Delamination

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Fracture of Engineering Materials (ME 225)

(advanced graduate course)

 

 

Content

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Introduction

Review of Elastic-Plastic Behavior of Materials

Macroscopic vs. Microscopic Deformation

Part I .  LINEAR ELASTIC FRACTURE MECHANICS (LEFM)

Overview

Stress Concentration Factors

Asymptotic Crack Tip Fields

Stress Intensity Factor Calibration

Crack Propagation Criteria

Limitations of Applicability of LEFM

Energy Relations in Elastic Crack Analysis

Part II.  NONLINEAR FRACTURE MECHANICS

Overview

Energy Relations in “Equivalent” Hyperelastic Materials

Asymptotic Analysis: HRR Fields

Limits of Applicability of Single-parameter Crack-tip characterizations:

            • Large-scale Yielding and Strain Hardening

            • J-integral and Crack-Tip-Opening Displacement (CTOD)

            • J-calibration Methods

Limits of Applicability of Single-parameter Crack-tip Displacements:

            • Stable Cracking and the R-curve

Stability Analysis (tearing)

Part III.  MICROMECHANICS OF FRACTURE

Dislocations

Microstructural Considerations

Strengthening and Toughening Mechanisms

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Tribology (ME 226)

(advanced graduate course)

 

Content

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Introduction

Surface interactions at various scales

Historical development of the study of nanomechanical surface interactions

Early friction and wear theories

Basic aspects of tribology problems

Surfaces

Nano-/macro-topography

AFM and STM surface imaging

Surface roughness parameters

Topography characterization (deterministic vs stochastic methods)

Real contact area (scale effects)

Material Properties

Bulk and surface material properties

Chemical reactivity

Surface energy

Work of adhesion

Mate­rial compatibility

Contact Surface Interactions

Origins of friction

Analysis of various friction nano-/micro-mechanisms

Friction force measurements at different scales

Concept of friction space

Friction mechanisms and adhesion in NEMS/MEMS and hard-disk drives

Nanoscale friction mechanisms

Implications of friction in nanotechnology and biotechnology

Lubrication

Lubrication regimes

Effect of load, speed, and roughness on lubrication efficiency

Solid film lu­brication

Boundary lubrication and modeling

Self-assembled monolayers

Solid-like behavior on confined monolayers

Frictional heating and lubricant effect

Chemical reac­tivity and additive functionality

Extreme-pressure lubricants and viscosity improvers

Antiwear additives

Ultrathin solid and liquid films at various temperatures

Rheological behavior of lubricant monolayers

Elastohydrodynamic lubrication

Wear

Types and uses of wear

Measurement of wear

Adhesion and asperity removal during sliding

Size and shape of adhesive wear particles

Abrasion, polishing; and grinding

Surface fatigue

Impact contact

Corrosion

Ero­sion

Fretting

Stick-slip

Nano-/micro-scale wear processes

Wear coefficient tables

Material Response to Surface Tractions

Introduction to contact mechanics

Hertz analysis

Contact analysis of layered media

Scale effects on contact deformation

Response of elastic-plastic solids to sliding/rolling contact loading

Plastic flow of the near-surface layer; shake­down, cyclic plasticity, and ratcheting

Void and crack nucleation

Crack propagation under mixed-mode loading

Delamination wear

Microstructure effects on delamination wear

Ultrathin-film mechan­ical property characterization methods

Nanoindentation and nanowear measurement and molecular dynamics modeling

Friction and Wear of Polymers and Polymeric Composites

Phenomenological observations

Basic friction mechanisms of polymers

Wear model for fiber-rein­forced polymeric composites

Friction and wear of biopolymers

Molecular analysis of stretched polymers

Basic surface physical chemistry of polymers

Chemical Wear

Brief introduction to metal cutting

Cutting tool materials

Abrasion; solution and diffusion wear

Tool wear monitoring techniques

Hard and soft protective overcoats

Methods for Improving Tribological Properties

Surface texturing at various scales

Modulated/patterned surfaces

Soft and hard overcoats

Ion implantation

Chemical and physical chemical va­por deposition

RF sputtering

Plasma spraying

Cathodic vacuum arc deposition

Laser surface alloying and cladding

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