If the material shows a degree of texture, the resultant pole figure will show the accumulation of poles about specific directions. A pole figure for a polycrystalline aggregate, which shows completely random orientation, does not necessarily appear as might naively be expected.Īngular distortions inherent in the stereographic projection result in the accumulation of points close to the centre of the pole figure as shown in the image below. Try altering their orientations so that all five are similar and then different, and notice how the positions of the poles change. Press 'Add grain' to add the, and directions of another grain, up to a maximum of four additional grains. This will alter the projections of the, and directions on the stereogram inside the rectangle. Occasionally, CD meaning cross direction is used instead of TD.ĭrag an atom in the green sphere to reorientate the unit cell of the grain under consideration. Typically, the external frame is defined by the normal direction, the rolling direction, and the transverse direction in a sheet ND, RD and TD respectively. Textured thin films.A pole figure is simply a stereogram with its axes defined by an external frame of reference with particular hkl poles plotted onto it from all of the crystallites in the polycrystal. Texture strength representation as fiber texture plots. Texture of MgO single crystal substrate material. Studying molecular arrays in a liquid crystal. Residual stress and texture mapping of friction stir welds. Rapid pole figure measurement of metal materials using a 2D detector. Off-normal fiber texture analysis by pole figure measurement using a goniometer equipped with an in-plane arm. High-resolution stress and texture measurements. Crystal orientation measurements of samples containing coarse grains. Highly versatile multipurpose X-ray diffractometer with built-in intelligent guidance. Distribution of crystallographic orientations In many cases, crystallographic texture preferred orientation can be introduced into a material during the fabrication process. Advanced state-of-the-art high-resolution XRD system powered by Guidance expert system software. The four peaks seen at the rim are Cu,andrespectively, due to the cubic structure of the copper lattices. The strong peak at the center of the pole figure indicates that the foil is preferably -oriented along the surface normal. The bottom two diagrams at right show the pole figure of a 50 micron thick Cu foil. The figure shows the pole figure in both in stereographic projection contour map and 3D display. The central dark red portion indicates texture along the direction. The top two diagrams at right show an in-plane pole figure of the reflection for a rolled steel sheet sample. The in-plane pole figure also allows a greater range of texture to be recorded, as it now contains the in-plane sample surface texture of the sample. In an in-plane pole figure, the incident beam, sample rotation, and detector angle are all moved, eliminating the necessity to tilt the sample. Traditional pole figure measurements are made by recording the intensity of a given Bragg reflection as a function of rotation and tilt of the sample. The typical measurement to determine texture is called a pole figure. Since texture can affect a material's properties by introducing structural anisotropy, it is desirable to measure a material's texture. For example, when steel sheets are rolled in the manufacturing process, a sheet texture is often produced. In many cases, crystallographic texture preferred orientation can be introduced into a material during the fabrication process.