Apparatus and method for determination of residual stress in crystalline substances

Claim 1

A quick and precise method for determination of residual stress in crystalline substances by locating a plurality of X-ray diffraction peaks with a single X-ray detector and without diffractometer shifting of said X-ray detector, said method comprising the steps of (a) focusing an X-ray source to direct X-rays at an angle with respect to a principal surface of a crystalline substance; (b) diffracting said X-rays; (c) receiving X-rays emanating from the substance in a single position-sensitive X-ray detector responsive to said X-rays to produce a multiplicity of ionizing events clustered about a position corresponding to a diffraction peak, said single position-sensitive X-ray detector including a collecting element providing first and second voltage pulses at respective first and second output ends of said detector in response to ionized particles, said first and second voltage pulses each having a rise time proportional to respective distances between the position of an ionizing event occurring within said detector and said first and second output ends of the collecting element; (d) locating a diffraction peak of said X-rays correlated with a first diffraction angle by determining rise times of the first and second voltage pulses produced in said collector, thereby indicating a position of an ionizing event occurring within said detector corresponding to a first diffraction peak; (e) varying a preselected angle the relationship between said X-ray source and said principal surface of the crystalline substance; and (f) locating a second diffraction correlated with a second diffraction angle by repeating steps (a) through (d), step (c) being performed with the same position-sensitive X-ray detector used for locating said first diffraction peak, a difference between the first and second diffraction angles being indicative of magnitude and direction of residual stress in the substances.