Mechanical Behavior of Materials Marc A. Meyers & Krishan K. Chawla Cambridge University Press.

Post on 28-Dec-2015

233 views 1 download

Tags:

transcript

Mechanical Behavior of Materials

Marc A. Meyers & Krishan K. Chawla

Cambridge University Press

Chapter 1Materials, 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

Different types of molecular chain configurations.

(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.

(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 ChainsAlpha 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. (Courtesy of M. Sarikaya and G. Mayer.)

SEM of fractured sponge spicule showing two-dimensional onion-skin structure of concentric layers.

(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 NanotubesThree 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