Solid state physics: Advances in research and applications

BOOK REVIEWS Solid State Physics : Advances in Research and Applications, Vol. 8. Edited hy I?. SEIYZ and 11. TUIINRULI.. Academic Press Inc., New York. Academic Books Ltd., London. 429 pp. $12. TEE sixth volume of this well-known series contains three articles directly relating to the mechanical properties of solids. The article ” Compression of Solids by Strong Shock Waves,” by Bice, McQueen and \Yalsh, reports work carried out at Los Alamos in which metals were subjected to pressures of up to several hundred thousand atmospheres with the help of explosives. From velocity measurements a Hugoniot curve can be constructed, that is, a curve showing the pressure and volume behind a shock wave with the shock wave velocity as parameter. The authors show how more orthodox thermodynamic curves (e.g. pressure-volume isotherms) can be deduced from the Hugoniot curve and a knowledge of the Griineisen constant of the material. I)ata for twenty-seven metals are plotted and tabulated. The theme of Professor Borelius’ article, ” Changes of State of Simple Solid and Liquid hletals ” is closely related ; he shows that a division of thermo-dynamic quantities into a vibrational part (given by a Debye function) and a remaining ‘ structural ’ part leads to a satisfactory correlation of the experimental facts. In ” Macroscopic Symmetry and Properties of Cryst;rls,” Charles S. Smith derives, largely I)g direct physical arguments, the restrictions which the symmetry of a crystal imposes on the arrays of coellicients which ciescril)e its physical properties. Tensors of up to the fourth rank arc c*onsidered. As his primary csample of a fourth-rank tensor the author considers not the familiar elastic constants, but the piezo-resistivity coellicients. Results for the elastic constants then follow at once on imposing the additional requirement that (with the usual two-suffix notation) the array of coefficients be symmetric. The rest of the volume is concerned with the electronic properties of solids. The articles by Piper and Williams (” Electroluminescence “), Dekker (“ Secondary Electron Emission “) and Givens (“ Optical Properties of hletals “) each contain experimental material and a theoretical discussion. In the final article (” Theory of the Optical Properties of Imperfections in Nonhletals “) Dexter guides the reader along the chain of approximations which leads from a precise quantum-mechanical formulation to a madageable theory. J. 1). ESHELBY

Solid State Physics and D. TURNBULL.

: Advances in Research and Applications, Academic

Press Inc., New Pork,

.4cademic

Vol. 7. Edited by l+‘. SErrz Books Ltd., London 525 pp.

$12. article in the present volume is Huntington’s comprehensive 160-page review of ” The Elastic Constants of Crystals.” It begins with an outline of macroscopic and atomic theory (including a sceptical look at the Lava1 theory) and a summary of methods of measurement. This is followed by tables of experimental results (with accompanying theoretical commentary) and an account of the effects of pressure and temper;tture. The final section discusses the influence of (among other things) lattice imperfection and superconductivity. A. F. Wells gives a refreshing treatment of “ The Structures of Crystals.” His starting point is not the theory of space-groups but rather the topological problem of linking atoms together. In “ Electron Energy Bands in Solids ” Callaway outlines modern methods of calculating band structures and gives a critical review of the results which have been obtained so far. Becker’s article (“ Study of Surfaces by Using New Tools “) is concerned with two new devices for investigating crystal surfaces. One is the simple and elegant field emission electron microscope of Miiller, and its more powerful offshoot the field-ion microscope, in which electrons are replaced by ions THF: LONGEST

79

80

BOOK

&3VlEWS

in order to increase the resolving power. The other is a rapid-acting ion gauge with which pressurechanges associated with adsorption and desorption can be studied. The remaining two articles deal with transport processes. Klcmens (” Thermal Conductivity and Lattice Vibrational Modes “) is concerned with the thermal conductivity of non-metals and the lattice component of the thermal conductivity of metals and alloys. As often in%solid state theory it proves easier to estimate the effect of imperfections that to solve the problem for the perfect crystal. Lewis’s article “ Wave Packets in Metals” discusses a troublesome technical point in conductivity theory. Roughly speaking, the difficulty is that for the usual perturbation theory to be valid the time occupied by an electron-phonon collision ought to be small compared with the time between collisions, and this condition, or rather its quantum-mechanical analogue, is commonly not satisfied. Specialists in this field will find the author’s point of view instructive. Others, even if they are not prepared to follow the argument in detail, will, perhaps, be reassured by his conclusion that results obtained by the orthodox treatment are in fact correct. J. D.

Elasticity D. E. R. GODFREY: Theoretical Hudson, London, 1959, 311 + x pp., 42s.

and

Plasticity

for

Engineers,

&HELBY

Thames and

THE FIRST part of this book would appear to be based on a course of lectures on elasticity delivered a few years ago by A. C. Stevenson to post-graduate mathematicians at University College, London. The first two chapters analyse stress and infinitesimal strain using the vector method, these are then related for an isotropic, homogeneous elastic body by invoking Hookc’s Law and the depen dence of the strain-energy on the strains only. Chapters III and V deal with pure bending and bending with shear respectively. The treatment of torsion in Chapter IV presents the well-known nmalytical solutions. A brief application of the conformal transformation method is given. The reviewer believes that the author has missed an opportunity in failing to introduce to engineers the idea of approximating to the value of the torsional rigidity by bounding methods. The torsion problem is particularly convenient as an introduction to such methods. Chapter VI is concerned with two-dimensional elasticity. This chapter serves a useful purpose by introducing the complex variable technique to the notice of the engineer, a thorough grasp of the methods here will help those going on to the advanced treatise by N. I. JIUSKI~ELISHVILI Some B&c Problems in the Chapter VII on curvilinear coordinates deals with the Mathematical Theo y of Elasticity. spherically and axially symmetric theory while Chapter VIII explains the ideas involved in the theory of concentrated and discontinuous loads in two and three dimensions. C’hspter IX is concerned with the theory of thin flat plates and here, the reviewer, although he agrees that Stevenson’s notation for stress-couples is logically superior to that usually used, cannot believe that it is useful to introduce it to engineers. Chapters X, XI and XII are entitled theory of plasticity. plastic bending and torsion of a beam and plane problems of plasticity respectively. It is the reviewer’s opinion that this part is so sketchy as to be practically worthless and as an introduction for engineers does not come up to The problems and solutions are a PRAGER and HODGE The Theory of Perfectly Plustic Solids. useful addition to the book. In the solution at the top of page 299, the error should read 27 per cent and not 6 per cent. The book is unfortunately marred by poor proof-reading (or bad printing), 60 being a lower bound for the number of accents over the stresses which have been omitted ! F. A. GAYDON