Patent ID: 6873681

Claim:
A method of estimating preferred orientation of a polycrystalline material comprising the steps of: (a) assuming an orientation density distribution function ρ which is axisymmetric on a normal direction of a surface of a sample made of a polycrystalline material, said orientation density distribution function ρ being a function of an angle φ at which a normal of a measurement lattice plane of a crystallite of the sample is inclined to the normal of the surface of the sample, and said orientation density distribution function ρ containing a characteristic parameter characterizing a form of the function; (b) measuring an intensity of a diffraction X-ray incident upon the surface of the sample at an incident angle α and reflected from said measurement lattice plane of the sample, and determining a change of the intensity of the diffraction X-ray from said measurement lattice plane with the incident angle α being changed to obtain a measurement rocking curve, wherein the diffraction X-ray from the measurement lattice plane has an angle 2θ 0 to an incident X-ray, and the incident angle α has a relationship of α=θ 0 +φ; (c) calculating a theoretical diffraction X-ray intensity based on said orientation density distribution function ρ to obtain a theoretical rocking curve including said characteristic parameter; and (d) determining said characteristic parameter so that said theoretical rocking curve approaches said measurement rocking curve as closely as possible, whereby said orientation density distribution function ρ is determined.