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

Biological Materials: Dental Implants in the Jawbone

Biological Materials: Typical Hip and Knee Prostheses

(a) Total hip replacement prosthesis (b) Total knee replacement prosthesis.

(a) Schematic representations of different classes of composites. (b) Different kinds of reinforcement in composite materials. Composite with continuous fibers made laminae in four different orientations.

Composites

Specific Modulus and Strength of Some Materials

Hierarchical Structure

Crystal Structure

Miller Indices

Hexagonal Structure

Some Common Crystal Structures

FCC and HCP Structures

(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

Structure of Glasses

(a) Ordered crystalline of silica (b) Random-network of glassy silica

Structure of Glasses

(c) Specific volume vs. temperature for glassy and crystalline forms of material

(c)

(d) (e)

(d) (e) Atomic arrangements in crystalline and glassy metals, respectively.

18

Trimodal Composite Composition

• Light weight structural composite. • Coarse grain additions increase ductility.

I.A. Ibrahim, et al., J. Mater. Sci. 26 p1137 (1991).

Density ρ (g/cc)

Young’s Modulus

(GPa)

CTE (1/°C)

Al 5083 2.66 70 26 x 10-6

B4C 2.51 460 6.1 x 10-6

ESK© Ceramics Tetrabor© Boron Carbide F1200

Al 5083 CG (~1 micron)

B4C (~1-7micron)

Cryomilled Al 5083 (~27-100 nm)

J. Ye et al. / Scripta Materialia 53 (2005) 481-486.

Trimodal Composite Microstructure

19 J. Ye et al. / Scripta Materialia 53 (2005) 481-486

TEM and HRTEM result of UFG/B4C interfaces (level 0)

(a)TEM image showing the B4C/UFG interface, (b) HRTEM image of B4C/UFG interface, the UFG grain is away from zone axis, (c) HRTEM image of B4C/UFG interface, the upper portion indicating an amorphous region between the B4C and UFG region, (d) HRTEM image indicates a lattice-level match between B4C and UFG Al.

Y. Li et al, Acta Materialia 59 (2011).

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 (Courtesy of H.D. Keith)

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

Molecular weight distribution curve (schematic). Various molecular weight parameters are indicated.

Liquid Crystals

Different types of order in the liquid crystalline state.

Mechanical Behavior of Biological Materials

Stress–strain curves for biological materials. (a) Urether. (After F. C. P. Yin and Y. C. Fung, Am. J. Physiol. 221 (1971), 1484.) (b) Human femur bone. (After F. G. Evans, Artificial Limbs, 13 (1969) 37.)

Crack Propagation in an Abalone Shell

(a) Cross section of abalone shell showing how a crack, starting at left, is deflected by viscoplastic layer between calcium carbonate lamellae (mesoscale). (b) Schematic drawing showing 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. (Adapted

from L. J. Gibson and M. F. Ashby, Cellular Solids: Structure and Properties (Oxford, U.K.: Pergamon Press, 1988), pp. 124, 125.)

(c) Schematic of a sandwich structure.

Biomaterial: Toucan Beak

(a) Toucan beak; (b) external shell made of keratin scales.

Foams: Synthetic and Natural

Cellular materials: (a) synthetic aluminum foam; (b) foam found in the inside of toucan beak.(Courtesy of M. S. Schneider and K. S. Vecchio.)

Biomaterials: Atomic Structure

Atomic structure of hydroxyapatite: small white atoms (P), large gray atoms (O), black atoms (Ca). (b) Atomic structure of aragonite: large dark atoms (Ca), small gray atoms (C), large white atoms (O).

Amino Acids

DNA Structure

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 haelix, 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.

Actin

Molecular structure of actin.

Muscle Structure

Biomaterial: 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

(a) Effect of applied field E on dimension of ferroelectric material. (b) Linear relationship between strain and electric field. (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: (a) arm chair; (b) “zig-zag”; (c) 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.)