ISSN:0889-311X    

DOI:10.1080/08893118908032947

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The integrated intensity of x-rays, neutrons or electrons diffracted by polycrystalline samples depends (among others) on the volume fractions of phases present in the samples, and on the structure factors and Debye-Waller factors. Hence, these quantities can. in principle, be determined from polycrystal diffraction diagrams. The relationship between measured intensity and these factors can be expressed relatively easily in the case of a random orientation distribution of the crystallites in the sample. Hence, the determination of one of these quantities generally requires the preparation of random samples. If the orientation distribution of the crystallites in the sample is not random, the same methods can, nevertheless, be applied, too, if the orientation distribution of the crystallites is properly taken into account by additional ‚texture factors’ which can be calculated for any (hklif the orientation distribution function is known. Experimental and theoretical methods of texture determination have been developed in the last two decades to a rather high degree of perfection thus allowing structure factor and Debye-Waller factor determinations as well as phase analysis in textured samples.

ISSN:0889-311X    

DOI:10.1080/08893118908032948

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Dislocation contrast in double crystal topography is studied from the view of reliable detection of the defects rather than of maximum strain sensitivity. In the range of most suitable diffraction angles between 40° and 60° for CuKα radiation wavelengths, dispersion corresponding to a difference in Bragg angles of about 1° causes a reduction in contrast and in image size of about 30%. Reliable detection of dislocations is possible up to differences of about 2° to 2.5°. Angles of incidence of the exploring beam to the sample surface below 15° cause successive reduction of image dimensions and strong contrast from surface irregularities and should therefore be avoided. The investigations aim at a greater versatility of this most cost-effective technique for real structure characterization.

ISSN:0889-311X    

DOI:10.1080/08893118908032949

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0889-311X    

DOI:10.1080/08893118908032946

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor