The Use of a Portable X-Ray Unit for Measuring Residual Stresses in Aluminum, Titanium, and Steel Alloys

Abstract

AbstractThe principles of measuring surface stresses in metals by X-ray diffraction with commercially available equipment are well known. Two techniques of making stress measurement by X-ray diffraction now in general use are (1) X-ray diffractometer with electronic control panel and (2) back-reflection film camera.The X-ray diffractometer technique has a number of important advantages over the film method, the major ones being accuracy and speed, but serious size and shape limitations are imposed on the specimen by the equipment: Because of its bulk and weight, specimens must be brought to it. The Airplane Division of The Boeing Company has capitalized on the advantages offered by the mobile backreflection film technique, especially with regard to specimen sizes and shapes. Results and techniques used, at Boeing for stress measurements in alloys of aluminum, titanium, and steel are presented. Experimental difficulties are discussed, and comparisons are made between results from the dirfractometer and backreflection camera, A portable darkroom and electropolishing unit are also presented which, with the X-ray unit, comprise a completely mobile stress-measuring facility.