Instruction

The following undergraduate and graduate courses are taught regularly by Professor Komvopoulos in the Department of Mechanical Engineering at the University of California at Berkeley.

Mechanical Behavior and Processing of Materials (ME 102A)

Course Outline

Introduction
Stress and Strain
Complex and Principal States of Stress and Strain
Yielding and Fracture Criteria
Mechanical Testing Methods
Elastic, Plastic, and Creep Deformation
Engineering Materials
Heat Treatment
Materials Selection
Effect of Notches
Fracture Mechanics
Fatigue under Fluctuating Stresses
Strain-Based Approach to Fatigue
Cumulative Fatigue Damage
Friction and Wear of Materials
Metal Cutting
Review of Manufacturing Processes
Laser Machining and Treatment
Ceramic Coating Technologies
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Lab Description
General
- brief history of CNC technology
- advantages leading to the adoption of CNC in production, short run and prototyping shops
- drawbacks which hinder the universal adoption of CNC
- discussion of the CAD-CNC relationship
Milling Machine
- description of the Mazac machining center
- establishment of coordinate system, workholding and part location measurement, tool registration and measurement
- demonstration of the programming interface
- demonstration of programmed operation
Wire EDM
- discussion of the history and variations of EDM processes
- description of the Fanuc EDM machine
- demonstration of the programming interface
- establishment of machine coordinates
- execution of program and the monitoring of cutting parameters
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Mechanical Behavior of Engineering Materials (ME 224)

Course Outline

Scope of course, 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 & 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, 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)

Course Outline

Introduction
Review of Elastoplastic Material Response
Macroscopic vs. Microscopic Deformation Behavior

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
J-calibration methods

Stable cracking and the R-curve

Part III. MICROMECHANICS OF FRACTURE
Dislocations
Microstructural considerations
Strengthening and toughening mechanisms
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Tribology (ME 226)*

Course Outline

Introduction
Surface interactions; historical development of the study of mechanical interactions; early friction and wear theories; basic aspects of tribology problems, topography and roughness measurement.

Basic Material Properties
Bulk and surface material properties; chemical reactivity; surface energy; work of adhesion; material com-patibility; real area of contact.

Contact Surface Interactions
The genesis of friction; analysis of various friction micromechanisms; friction force measurement; friction-space concept; microscale friction mechanisms; stiction in MEMS and information storage systems.

Lubrication
Lubrication regimes; effect of load, speed, and roughness on lubrication efficiency; solid film lubrication; boundary lubrication and modeling; frictional heating and lubricant effect; chemical reactivity and additive functionality; EP lubricants and viscosity improvers; behavior of solid and liquid films at various tempera-tures; rheological behavior of thin lubricant films and implications to the head/disk interface; basic elastohy-drodynamic theory of lubrication.

Wear
Types and uses of wear; measurement of wear; adhesion; asperity removal during sliding; size and shape of adhesive particles; abrasion; polishing; grinding; surface fatigue; impact; corrosion; erosion; fretting; stick-slip; tabulation of wear coefficients.

Response of Materials to Surface Traction
Introduction to contact mechanics; Hertzian analysis; contact analysis of layered media; response of elastic-plastic solids to sliding/rolling contact loading; plastic flow of the near-surface layer; shakedown, cyclic plas-ticity, and ratchetting; void and crack nucleation; crack propagation under mixed-mode loading; delamination wear model; microstructural effects on delamination; thin-film mechanical property characterization methods; nano-scale tribotesting.

Friction and Wear of Polymers and Polymeric Composites
Phenomenological observations; basic friction mechanisms of polymers; wear model for fiber-reinforced polymer composites; friction and wear of the magnetic recording head/tape interface; plasma treatment and tribology of polymeric joint implants.

Chemical Wear
Brief introduction to metal cutting; cutting tool materials; abrasion; solution and diffusion wear; tool wear monitoring techniques; protective hard overcoats.

Novel Methods for Improving Friction and Wear Properties
Modulated surfaces; soft and hard overcoats; ion implantation; chemical and physical chemical vapor deposition; sputtering; plasma spraying; cathodic arc deposition; laser surface treatments.
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*This course is also offered annually as an intensive five-day course through the UC Engineering Extension.

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Latest update May 18, 2001