摘要:

Previous calculations (Brandon and Perry 1967, Perry and Brandon 1968) have now been extended to cover the case of a single ribbon of stacking fault separating two parallel Shockley partial dislocations in a hemispherical f.c.c. crystal. Image forces are neglected and classical isotropic elasticity theory is used throughout.

ISSN:0031-8086    

DOI:10.1080/14786436808227356

出版商:Taylor & Francis Group    

年代:1968

数据来源: Taylor

摘要:

A time-of-flight technique was used to determine the energy spectrum of atoms ejected by ion bombardment from a metal target. The ion beam was pulsed in synchronism with a magnetically suspended rotor, spinning at speeds up to 3000 rev. sec−1. The flight path of 50 cm between target and rotor was sufficient to obtain a dispersed deposit of atoms on the rim of the rotor for all atom energies up to about 10 kev. The deposit was detected with auto-radiography by means of its radioactivity, the Cu or Au targets having been previously activated by irradiation with thermal neutrons.

ISSN:0031-8086    

DOI:10.1080/14786436808227357

出版商:Taylor & Francis Group    

年代:1968

数据来源: Taylor

摘要:

Using the technique described in part I, the energy spectrum of sputtered atoms has been determined for several gold specimens, both single crystals and polycrystalline aggregates. The ⟨110⟩, ⟨110⟩ and ⟨121⟩ directions of ejection were chosen for the experiments. Bombardment was with either 43 kev A+ions, 43 kev Xe+ions or 66 kev Xe+ions.

ISSN:0031-8086    

DOI:10.1080/14786436808227358

出版商:Taylor & Francis Group    

年代:1968

数据来源: Taylor

摘要:

In Cu results generally similar to those for Au are found, but with a reduction of all focusing energies. Ejection in a direction away from a focusing or channelling axis, gave a spectrum that fitted extremely well to the random cascade model.

ISSN:0031-8086    

DOI:10.1080/14786436808227359

出版商:Taylor & Francis Group    

年代:1968

数据来源: Taylor

摘要:

When polycrystalline lead is subjected to simple shear stress by the method originated by Andrade and Jolliffe, the intersections of the slip planes in the crystal grains with the surface of the specimen appear as marked straight lines, the angular distribution of which is distinctive. In particular, the preferred direction of the lines is either in the direction of, or normal to, the direction of stress and there are practically no lines making an angle of 45° with these directions. Measurements have been made of the angular distribution of the lines for a strain of about 0·06 produced by two different stresses. A quantitative theory, based on certain simplifying assumptions, has been worked out which agrees with observation in predicting no lines at45° and flat maxima in the neighbourhood of 0° and 90° with the direction of stress. The agreement in detail is good for the lower stress, which entails a long time of flow.

ISSN:0031-8086    

DOI:10.1080/14786436808227360

出版商:Taylor & Francis Group    

年代:1968

数据来源: Taylor

摘要:

This note reports some preliminary results of a combined field-ion microscope and electron microscope study of a pure iron alloy containing 2 wt. % vanadium and 0·2 wt. % carbon. After isothermal transformation particles of vanadium carbide are formed with a size and distribution which depends on the heat treatment conditions. A course particle microstructure was used to determine the nature of the field-ion image from these carbides and the study was then directed at samples which were heat treated to produce a microstructure on a finer scale where the amount of information which could be obtained from the electron microscope was slight.

ISSN:0031-8086    

DOI:10.1080/14786436808227361

出版商:Taylor & Francis Group    

年代:1968

数据来源: Taylor

摘要:

Experimental Magnetochemistry—Nonmetallic Magnetic Materials. By M. M. Schieber. (North-Holland Publishing Company, 1967.) [Pp. 572.] Price £9 0s. 0d.

ISSN:0031-8086    

DOI:10.1080/14786436808227362

出版商:Taylor & Francis Group    

年代:1968

数据来源: Taylor