SU1453159A1 - Method of measuring internal stresses in specimens - Google Patents

Abstract

The invention relates to a measurement technique and can be used in determining the stress state of parts and structures. The purpose of the invention is to improve accuracy. This is achieved by marking the sample in equal symmetrically located locations. relative to the plane of symmetry of the sample part, cutting the sample on the part of removing material layers from two symmetrically located parts of the sample so that the removed layers of one part of the sample are arranged perpendicularly removable layers of material of another part of the sample, applying special bases to measure deformations the sample and on the surfaces formed after each cutting of the sample in the separation of the next part of the sample, using the data obtained to determine the stresses. The method for determining the intrinsic stresses in the sample allows the stress state of the sample to be determined with high accuracy. 2 Il. (L

Description

4 SP

00

sd

The invention relates to a measuring technique and can be used in determining the stress state of machine parts and components. Structure:

The purpose of the invention is to increase the measurement accuracy.

Fig. 1 shows a diagram of the deposition and marks on the end surface of the sample (marks A, B, B, C, C), bases for measuring deformations on the side surface of the sample (points 1-6, 1, 1, 2, 2 ), dividing the sample into parts with cuts running through the marks, and removing layers from parts of the sample after cutting it into parts; in fig. 2 is a diagram of applying bases on surfaces formed in the sample after cutting one part from it.

The method is implemented as follows.

On the end surface of the sample, the marks are equally spaced and symmetrically relative to the longitudinal plane of symmetry of the sample, so that the longitudinal plane of symmetry of the sample passes through one of the marks (mark A), and the parallel side surfaces of the sample each others; labels (marks С, с). Then, on one of the side surfaces parallel to the longitudinal symmetry plane of the image, bases are applied to measure the deformations according to the scheme: to measure the relative change in the linear dimensions of the cut part, an even number of points are put in pairs, arranged in one line along the length of the sample at a point at each of the ends (points 1, 2 and 1, 2, fig. 1), to register bending deformations of the cut-off part, the number of points is multiplied by three, located on one line along the sample length at a point at each of the ends and one in the middle them (points 1-6). The sample is successively cut into parts, the parts separated by plane parallel to the longitudinal plane of symmetry of the sample with the cuts passing through the marks. After each successive cutting off of the part, the bases are applied on the surface resulting from the cutting of the sample, according to the described scheme (Fig. 2). Using a sample applied to the side surface and

the surfaces resulting from the cutting, the bases are measured deformations in the parts cut from the sample. After the sample has been completely cut into pieces, two parts are taken, which in the whole sample are located symmetrically with respect to the longitudinal plane of symmetry of the sample, and the material layers are removed from them so that the layer to be removed from one part of the sample is perpendicular to the layer removed registering with this bending deformation of the removed material layers. The data obtained determine the stress state of the sample before cutting.

The use of the method makes it possible to increase the accuracy of determining internal stresses due to the special marking associated with the symmetry of the sample by marking it before cutting into parts, with a special scheme for removing material layers from parts of the sample.

Claims (1)

Invention Formula The method for determining the internal stresses in a sample, in which a sample is cut into pieces, determines the deformations in the cut parts, according to the data obtained, the stresses in the sample are calculated, characterized in that, in order to improve the measurement accuracy, before cutting, they are marked on the end face. the sample surfaces are equidistant and symmetrically with respect to the longitudinal plane of symmetry of the sample, positioned marks, and so that the longitudinal plane of symmetry of the sample and the lateral surfaces of the sample parallel to it pass through each Well, from such marks, then on one nz of lateral surfaces parallel to the longitudinal plane of symmetry of the sample, bases are applied for measuring deformations according to the scheme: to measure the relative change in linear dimensions of the cut part, an even number of points are put in pairs, positioned along the length of the sample along a point at each of the ends, to register the bending deformations of the cut-off part, the number of points is multiplied by three, located on one line along the length of the specimen at the point at each of the ends and one in the middle between by them. the sample is cut into parts in series, cutting off the part with flat cuts passing through the marks parallel to the longitudinal plane of symmetry of the sample, before cutting the next part on the surface resulting from the previous cutting, reapply the base according to the described scheme, after completely cutting the sample into parts two Editor N. Bobkova Compiled by V.Kurl ndsky Tehred M.Didzh parts that are generally in the sample are located symmetrically relative to the longitudinal plane of the sample, and remove material layers from them so that the removable layer from one part of the sample is located perpendicular to the layer removed from the other part of the sample, registering the bending deformations of the removable material layers. 5 L Fi.2 Proofreader L. Pilipenko