摘要:

AbstractThis paper presents a systematic survey on the formation of recrystallisation textures in cold rolled Al alloys. In particular, the nucleation of new grains in cube bands, grain boundaries, shear bands, and the deformation zones around large pProceedings of Conference 'Texture on a Mircoscale' as well as their subsequent growth into the deformed matrix are examined and discussed in the context of their contribution to the final recrystallisation textures. In addition to X-ray macrotexture analysis, particular attention is focused on the determination of local orientations by electron diffraction either in the transmission electron microscope (microbeam electron diffraction) or, at later stages of recrystallisation, in the scanning electron microscope (electron backscattered diffraction). A combination of these complementary techniques for orientation determination with increasing spatial resolution yields much more valuable information on the underlying mechanisms of recrystallisation than is accessible by the sole use of the individual techniques.MST/3676

ISSN:0267-0836    

DOI:10.1179/mst.1996.12.10.859

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

AbstractNickel base superalloy and aluminium single crystal and polycrystalline specimens have been examined using mechanical property microprobe (MPM) measurements and electron backscatter patterns (EBSPs) as a function of applied strain. Grids of lines deposited on to the specimens before three point bending were used to determine the macroscopic strain. The MPM, or nanoindenter, has been used to produce arrays of five by three indents across the edge of the specimens, both before and after bending. Electron microscope film EBSPs have been produced from regions within the nanoindenter arrays. The effects of strain can be seen in the change in Kikuchi band profile and thus EBSP‘image quality’and in changes in the hardness of the sample. Software is being developed to quantify these differences. It has been found that when the nickel base superalloy calibration specimens were bent, stress relief occurred by the formation of slip bands. This caused problems with strain calibration, and alternative methods are being investigated.MST/3677

ISSN:0267-0836    

DOI:10.1179/mst.1996.12.10.873

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor

摘要:

AbstractA number of approaches for graphically representing electron backscattered diffraction grain orientation measurements are presented, using as examples the distributions and variations of texture in two 8090 AI–Li alloys. In this manner the component orientations constituting the overall texture can be illustrated readily and their relative volume fractions calculated. The locations of texture components can be represented by texture distribution plots. The power of Mackenzian plots is illustrated by demonstrating their capacity to represent the degree of scatter about an ideal orientation, show differences in distribution that may be either real or due to specimen preparation, and highlight when two ideal orientations that are very close to each other, namely, {110}〈112〉and {110}〈335〉in this work, may be present.MST/3465

ISSN:0267-0836    

DOI:10.1179/mst.1996.12.10.880

出版商:Taylor&Francis    

年代:1996

数据来源: Taylor