Transcript Slide 1

Mechanical Behavior of
Materials
Marc A. Meyers & Krishan K. Chawla
Cambridge University Press
Chapter 1
Materials, Structure, Properties, and
Performance
Thomas’s Iterative Tetrahedron
Properties of Main Classes of Materials
Biomaterials: Dental Implants in the
Jawbone
Steps required for insertion of implant into mandible.
(Courtesy of J. Mahooti.)
Biomaterials: Typical Hip and Knee
Prostheses
Total hip replacement prosthesis
Total knee replacement prosthesis.
Composites: Schematic representations
of different classes
Composites:
Different Types of Reinforcement
Specific Modulus and Strength
of Some Materials
Hierarchical Structure: Biological and
Synthetic Materials
Tendon
Advanced
Synthetic
Composite
Crystal Structures:
7 Crystal Systems, 14 Bravais lattices
Directions in Cubic Unit Cell
Miller Indices for Planes in Cubic Cell
Direction and Planes:
Miller Indices
Hexagonal Structure
Three to four index conversion
Three Most Common Crystal Structures
(001) Plane in Molybdenum
Atomic Resolution Transmission Electron Microscopy; Courtesy R. Gronsky
FCC and HCP Structures: Stacking of
Closest Packed Planes
(a)Layer of most closely packed atoms corresponding to
(111) in FCC and (00.1) in HCP.
(b) Packing sequence of most densely packed planes in
AB and AC sequence.
(c) Ball model showing the ABAB sequence of the HCP
structure.
(d) Ball model showing the ABCABC sequence of the
FCC structure.
Different Structures of Ceramics
Ordered Structure: Intermetallic Compound
Important Intermetallic Compounds
Structure of Glasses
Ordered crystalline of silica
Random-network of glassy silica
Structure of Glasses
(c)
Atomic arrangements in crystalline and glassy metals
Glasses and Crystals: Specific Volume
Classification of Polymers
(a) Homopolymer: one type of repeating unit.
(b) Random copolymer: two monomers, A and B,
distributed randomly.
(c) Block copolymer: a sequence of monomer A,
followed by a sequence of monomer B.
Different types of molecular chain
configurations.
(d) Graft copolymer: Monomer A forms the main
chain, while monomer B forms the branched
chains.
Tacticity in Polypropylene
Tacticity : Order of placement of side groups.
Crystallinity of Polymers
A lamellar crystal showing growth spirals
around screw dislocations. TEM.
(Courtesy of H.D. Keith.)
Spherulitic structures:
a.Spherulitic structure
b. Each spherulite consists of
radially arranged,
narrow crystalline lamellae.
c. Each lamella has tightly packed
polymer chains folding back
and forth
Polymer Chain Configuration
Molecular Weight Distribution in Polymers
Liquid Crystals
Different types of order in the liquid crystalline state
Stress-Strain Curves for Biological Materials
Urether
(After F. C. P. Yin and Y. C. Fung, Am.
J. Physiol. 221 (1971), 1484.)
Human femur bone
(After F. G. Evans, Artificial
Limbs, 13 (1969) 37.)
Crack Propagation in an Abalone Shell
Cross section of abalone shell
showing how a crack, starting at
left, is deflected by viscoplastic
layer between calcium carbonate
lamellae (mesoscale).
Arrangement of calcium carbonate in nacre,
forming a miniature“brick and mortar”
structure (microscale).
Porous and Cellular Materials
Compressive stress–strain curves for foams.
(a) Polyethylene with different initial
densities.
(b) Mullite with relative density = 0.08.
(c) Schematic of a sandwich structure.
L. J. Gibson and M. F. Ashby, Cellular Solids: Structure and
Properties (Oxford, U.K.: Pergamon Press, 1988), pp. 124,
125.)
Biological Material: Toucan Beak
Toucan beak
External shell made of keratin scales
Foams: Synthetic and Natural
Synthetic aluminum foam
Foam found in the inside of toucan beak
Courtesy of M. S. Schneider and K. S. Vecchio.
Biological Minerals: Atomic Structure
Atomic structure of hydroxyapatite:
small white atoms (P), large gray atoms (O),
black atoms (Ca).
Atomic structure of aragonite:
large dark atoms (Ca), small gray atoms (C),
large white atoms (O).
Courtesy K. S. Vecchio
Amino Acids
Missing eqn
Polypeptide Chains
Alpha Helix and Beta Sheet Structures
Collagen
Triple helix structure of collagen
Adapted from Y. C. Fung, Biomechanics: Mechanical Properties of Living Tissues (Berlin:
Springer, 1993).
Collagen: Hierarchical Structure
Hierarchical organization of collagen,
starting with triple helix,
and going to fibrils.
(From H. Lodish et al., Molecular Cell Biology,
4th ed. (New York, W.H. Freeman & Company,
1999).)
Mechanical Properties of a Collagen Fiber
Idealized configuration of a
wavy collagen fiber.
Stress–strain curve of collagen with three
characteristic stages.
Muscles:Actin
Molecular structure of actin.
Muscles: Myosin
Muscles:
Movement of Actin and Myosin Filaments
Action of cross-bridges when actin filament is moved to left with respect to myosin
filament; notice how cross-bridges detach themselves, then reattach themselves to
actin.
Muscle Structure: Sarcomere Units
Muscle Structure: Myofibril
Muscle Hierarchical Structure:
from Fibrils to Fibers
Biological Material: Sponge Spicule
Stress-deflection responses of synthetic
silica rod and sponge spicule in
flexuretesting.
SEM of fractured sponge
spicule showing twodimensional onion-skin
structure of concentric layers.
(Courtesy of M. Sarikaya and G. Mayer.)
(Courtesy of G. Mayer and M. Sarikaya.)
Active (Smart) Materials:Ferroelectricity
(a)Effect of applied field E on
dimension of ferroelectric
material.
(b) Linear relationship between
strain and electric field.
(a) (Courtesy of G. Ravichandran.)
Electronic Materials
Cross section of a complementary metal-oxide semiconductor (CMOS).
(Adapted from W. D. Nix, Met. Trans., 20A (1989) 2217.)
Nanomaterials: Carbon Nanotubes
Three configurations for single wall carbon
nanotubes:
arm chair;
“zig-zag”;
chiral.
(Adapted from M. S. Dresselhaus, G. Dresselhaus and R. Saito, Carbon,
33 (1995) 883.)
Nanomaterials: Carbon Nanotubes
Array of parallel carbon nanotubes grown as a forest.
(From R. H. Baughman, A. A. Zakhidov and W. A. de Heer, Science, 297 (2002) 787.)
Strength of Copper Whisker
Strength of Whiskers
Tensile Strength of Whiskers at R. T.
Turbine Blade Subjected to Centripetal Forces