SU561109A1

SU561109A1 - Method of testing materials for brittle fracture resistance

Info

Publication number: SU561109A1
Application number: SU1691855A
Authority: SU
Inventors: Андрей Александрович Чижик
Original assignee: Предприятие П/Я А-3513
Priority date: 1971-08-30
Filing date: 1971-08-30
Publication date: 1977-06-05

Description

1one

Изобретение относитс к исследоваипо механических свойств конструкционных материаловг в частности к определению параметров распространени и остановки крупных грещин.The invention relates to the study of the mechanical properties of structural materials, in particular, to the determination of the parameters of the propagation and stopping of large crevices.

Известен способ испытани на в зкость разрушени , заключающийс в испытании образца с надрезом и измерении усилий, сооГветствующих моменту распространени трещины ,There is a known method for testing the fracture viscosity, consisting in testing a notched specimen and measuring forces corresponding to the moment of crack propagation,

Недостатком этЬго способа вл етс испытание большого количества образцов при различных состо ни х исследуемого материала .The disadvantage of this method is the testing of a large number of samples in various states of the material under study.

Наибопее близким по технической сущ кости и достигаемому эффекту к предпагае- мому изобретению вл етс способ ИСПЫТЕ - ни материалов на сопротивление хрупкому разрушению, заключающийс в том, что в образце с концентратором непр жений создают неоднородность его механических свойств известным методом, например неравномерга 1м нагревом, подвергают образец раст гивающей нагрузке, инециируюг трещину в хрупком слое, регистрируют распространенйе трешины в теле образца, а характеристикой свойств материала служит параметр метода, например температура, определ ющий механические свойства материала в месте остановки трещины .The closest in technical essence and the achieved effect to the proposed invention is the TEST method of materials for resistance to brittle fracture, which consists in the fact that, in a sample with a non-strain concentrator, a non-uniformity of its mechanical properties is created by a known method, for example, non-uniformity of 1m heating, subject the sample to tensile load, inject a crack in the brittle layer, register the propagation of cracks in the sample body, and the parameter of the method, for example p is the temperature that determines the mechanical properties of the material at the site of the crack.

Недостатком указанного способа вл ет с необходимость проведени испытаний при нескольких уровн х прочности материала на большом количестве образцов.The disadvantage of this method is the need to test at several levels of material strength on a large number of samples.

Предлагаемый способ отличаетс от известного тем, что неоднородность мехагшческих свойств создают неоцнороцной тер- мической обработкой образна, а параметром служат механические свойства, с-преде- пенные на пробах, которые отбирают в месте останова хрупкой трещины.The proposed method differs from the well-known in that the heterogeneity of the mechanical properties is created by neo-thermal heat treatment in the form, and the mechanical properties, c-predetermined on the samples, which are taken at the break point of a brittle crack, serve as a parameter.

Это позвол ет повысить производительность способа за счет оаковремен ого испьтани при нескопьких уровн х прочности на одном образце.This makes it possible to increase the productivity of the method due to accelerated testing at several levels of strength on one sample.

Предлагаемый способ осуществл етс следующим образом.The proposed method is carried out as follows.

Claims

In a sample with a notch that serves as a stress centering device, by non-uniform thermal processing, they create a non-electrical AOE mechanical properties. Then the sample is subjected to tensile load Kv, a crack is initiated in the concentrator area, and the distribution of the trash in the sample body, the BifnoTb time of its spontaneous stopping, is recorded. After that, the sample is removed from the grips of the loading device, hardness is measured along the design part, and a calibration graph is built. In the place of stopping, the standard specimens are cut out and, on the basis of its tests, the mechanical properties of the material are used, which are a parameter of the resistant material to brittle fracture. The invention The method of testing the material to resist brittle fracture is due to the fact that in a sample with a stress concentrator they create a non-uniformity of its mechanical properties with a known metope, for example by uneven heating, subject the sample to a tensile load, and the fractures were fractured in a fragile layer, and there was a spread with a tensile load, and the fractures were fractured in a fragile layer, and the samples were spread with a tensile load. sample, and the characteristic of the properties of the material is the parameter of the method, for example, the temperature that determines the mechanical properties of the material at the site of the crack m and n and h Yusch and with the fact that, in order to increase process efficiency, heterogeneity of mechanical properties sample creates nonuniform thermal treatment, and the parameters are rum mechanical properties opredeletshye on samples that were taken at the site of a brittle crack stop. Sources of information taken into account in the examination: 1. German I. The rigidity and strength of steel parts. Moscow, Mashinostroenie, 197O, p. 269. a.Robertsbfi T.0.: Ero-pa SteeEj; i955, No. 5, 201 - 2O8.