A high-strength martensite–austenite multilayered steel was employed for further verification of the reliability of simultaneous Rietveld analysis of multiphase textures and macro stress tensors. Pole figure evaluation of a limestone standard sample with a well known texture suggested that the precision obtained for texture measurement is comparable to that of the established neutron beamlines utilized for texture measurement, such as the HIPPO diffractometer at the Los Alamos Neutron Science Center (New Mexico, USA) and the D20 angle-dispersive neutron diffractometer at the Institut Laue–Langevin (Grenoble, France). A procedure for combined high stereographic resolution texture and residual stress evaluation was established on the pulsed-neutron-source-based engineering materials diffractometer TAKUMI at the Materials and Life Science Experimental Facility of the Japan Proton Accelerator Research Center, through division of the neutron more » detector panel regions. can be derived from neutron diffractograms. Furthermore, crystallographic parameters and other valuable microstructure information such as phase fraction, coherent crystallite size, root-mean-square microstrain, macroscopic or intergranular strain and stress, etc. Neutron diffraction texture measurements provide bulk averaged textures with excellent grain orientation statistics, even for large-grained materials, owing to the probed volume being of the order of 1 cm 3. The time required for preparation, measurement, and analysis is of the order of 45 to 60 min. The exact procedure requires attention to grain size, specimen preparation, and indenter load. To determine preferred orientation qualitatively from hardness data requires a minimum of twelve measurements per plane on three, preferably orthogonal, planes. A quantitative relationship with inverse pole figure data was also obtained. With use of an empirical relationship between the single crystal hardnesses and more » those of the polycrystalline material conventional pole figures could be constructed which compare favorably with those determined by x-ray diffraction. Data from the single crystals was used to construct a polar coordinate hardness contour map. The variation of Knoop microhardness measurements on selected planes as a function of indenter axis relative to crystallographic or fabrication directions was determined for four lots of polycrystalline Zircaloy-2, on which both conventional and inverse pole figures had been determined, and seven Zircaloy-2 single crystals. Knoop microhardness measurements were investigated as a solution to this problem. « lessĪ rapid and semiquantitative method of determining preferred orientation on large numbers of Zircaloy-2 specimens was desired. The experimental and theoretical results suggest that the initial texture due to hot rolling was insignificant as compared with the texture induced by large strains under plane-strain compression. The experimental pole figures were consistent with the findings in the theoretical study. The uniaxial tensile stress-strain curve and the plane-strain, compressive stress-strain curve of the sheet were used to calibrate the material parameters in the model. These figures are compared with the theoretical pole figures produced from a Taylor-like polycrystal model based on a pencil-glide slip system. The grain more » structure after plane-strain compression was studied by optical microscopy, and the new deformation texture was characterized by x-ray diffraction pole figures. =, and perpendicular to the rolling direction.
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