Mapping of Strain Tensor Components in Polycrystalline Samples using EBSD.

The advance in Electron Backscatter Diffraction known as High Resolution EBSD has permitted the strain tensor components and neighbour disorientation measurements to be mapped at resolutions better than 2 parts in 10000. Following earlier research into this technique which was focused on verifying the sensitivity and accuracy of the measurements, recent studies have involved investigations on semiconductor and metallic polycrystalline materials. In particular observations of localized regions where residual strains exceeded the macroscopic yield stress have been thoroughly investigated to eliminate experimental error as a possible explanation. No such cause was found. Strain measurements on polycrystalline steels in uniaxial tension and during thermal stress relieving thermal treatment have also been carried out. Maps of the strain distribution during elastic loading and early stages of plastic flow showed hot spots of high strain as in the static tests but overall the measured elastic strain was equal to the applied strain.