SU1455229A1

SU1455229A1 - Method of determining stresses in case of elastic load of specimen

Info

Publication number: SU1455229A1
Application number: SU864091371A
Authority: SU
Inventors: Виктор Владимирович Курляндский; Александр Искандерович Бикулов
Original assignee: Московский институт инженеров водного транспорта
Priority date: 1986-07-16
Filing date: 1986-07-16
Publication date: 1989-01-30

Abstract

Изобретение относитс к измерительной технике и может эффективно использоватьс при исследовани х прочности образцов сложной формы, выполненных из анизотропных хрупких материалов. Цель изобретени - рас- ширение области применени путем обеспечени определени распределени напр жений в хрупких образцах при разрушающих нагрузках. Дл этого изготавливают группу идентичных образцов, на одном из которых измер ют изменение геометрических размеров под действием исследуемой нагрузки , а на других последовательно снимают поверхностные слои материала на различную глубину, после чего их подвергают обработке, снимающей остаточные напр жени , и нагружают фиксированной нагрузкой, регистриру изменение их геометрических размеров . 2 ил. СЛThe invention relates to a measurement technique and can be effectively used in studies of the strength of samples of complex shape made of anisotropic brittle materials. The purpose of the invention is to expand the field of application by providing a definition of stress distribution in fragile specimens under breaking loads. To do this, a group of identical samples is made, one of which measures a change in the geometric dimensions under the action of the test load, while on the other, the surface layers of the material are successively removed to different depths, after which they are subjected to treatment, relieving residual stresses, and loading change their geometric dimensions. 2 Il. SL

Description

1one

Изобретение относитс к измерительной технике и может эффективно использоватьс при исследовани х прочности образцов сложной формы, выполненных из анизотропных хрупких.материалов .The invention relates to a measurement technique and can be effectively used in studies of the strength of samples of complex shape made of anisotropic fragile materials.

Цель изобретени - расширение области применени способа путем обеспечени определени распределени напр жений в хрупких образцах при разрушающих нагруг-ках.The purpose of the invention is to expand the scope of application of the method by ensuring the determination of the distribution of stresses in brittle samples during destructive loading.

На фиг.1 изображена схема операций, выполн емых на исследуемом образце, при осутчествлении предлагаемого способа; на фиг.2 - то же, на образ- с цах, идентичных исследуемому.Figure 1 shows a diagram of operations performed on the sample under study, if the proposed method is depleted; figure 2 - the same, on samples with identical to the test.

На фиг,1 и 2 прин ты следующие обозначени :In FIGS. 1 and 2, the following notation is used:

10ten

с with

10ten

Q - исследуема нагрузка; Р - фиксированна нагрузка; A,B,C,D,K,M - точки гфиложени нагрузки и установки деформометров.Q - load under study; P - fixed load; A, B, C, D, K, M are the points of load loading and installation of deformometers.

Способ осуществл ют следующим образом .The method is carried out as follows.

Исследуемый образец нагружают исследуемой разрушающей нагрузкой Q в точках К и М, контролиру деформо- метром изменение размера АВ. На группе других образцов, идентичных исследуемому по геометрии, материалу и способу изготовлени , последовательно удал ют слои материала, причем в каждом из них на свою глубину. Образцы с удаленным слоем подвергают обработке , снижающей остаточные напр жени , внесенные при сн тии слоев, иThe sample under test is loaded with the test load Q under study at points K and M, and the size of the AB is controlled by a strain meter. On a group of other samples that are identical to the material examined by geometry, and method of manufacture, layers of material are successively removed, with each of them at its depth. Samples with a removed layer are subjected to a treatment that reduces the residual stresses introduced during the removal of the layers, and

4i4i

сл ел to tolistened to to

:о:about

ь агружают в точках А и ,В фиксирован i|oft нагрузкой Р, контролиру деформо- «етром изменени размеров КМ и CD.. По результатам измерений, выпол- Йенных на исследуемом образце и на фдном из идентичных образцов со «рн тым слоем, определ ют напр жение р исследуемом слое, исход из законаl is loaded at points A and, B is fixed i | oft with load P, controlled by deforming changes in dimensions of KM and CD .. According to the results of measurements performed on the test sample and on the base of identical samples with are the voltage p of the test layer, based on the law

разрушающей нагрузкой с точностью до величины начальных остаточных напр жений , обусловленных технологией его изготовлени .breaking load with an accuracy of the initial residual stresses caused by its manufacturing technology.

Claims

Invention Formulation Method

If) equality of work on reciprocal movements under elastic loading of the sample,

The problem is that the sample is loaded; the test load and measure the change in the geometric dimensions of the sample due to the action of the test load, successively remove the material layers from the sample, load the sample with a removed layer of a given thickness and from 1 x with a fixed load

6- &CD; d F QuK M; R, DAV,

Where

G; - the required stresses in the 1st layer of the sample under study;

F- is the surface area formed in an i-OM identical sample due to the absence of a layer of material; UAB - change in the size of AB when loading the sample under study from the load 0;

iCD; and

UKM- - changes in the sizes of CD and KM when loading an identical i-ro sample with a removed layer of load P. The set of obtained voltage values in different layers makes it possible to establish the dependence of the stress distribution over the thickness of the test sample when it is loaded

measuring the change in its geometrical 20 dimensions from the action of a fixed load, according to the measurement results, the stresses in the sample layer under study are determined, so that, in order to expand the range of application, by providing a definition of the stress distribution in brittle loads, removal of layers of material are performed on other samples, 30 identical to the test, and at different depths in each of them, and before loading with a fixed load of these samples they are subjected to processing, removing residual stresses.

breaking load with an accuracy of the initial residual stresses caused by its manufacturing technology.

Invention Formulation Method

measuring the change in its geometrical dimensions from the action of a fixed load; according to the measurement results, the stresses in the sample layer under study are determined, so that, in order to expand the range of application, by determining the stresses in fragile samples under breaking loads, The removal of layers of material is carried out on other samples identical to the studied one, and to different depths in each of them, and before loading with a fixed load on these samples they are subjected to processing, removing residual stresses.

at

fpus.i

WITH

Fie.2