1、DC 62-419 : 620.172 DEUTSCHE NORM February 198: I I Testing of sandwiches Tensile test perpendicular to the faces I 53292 _ Prfung von Kernverbunden; Zugversuch senkrecht zur Deckschichtebene Supersedes July 1976 edition As it is current practice in standards published by the International Organizat
2、ion for Standardization (ISO), the comma has been used throughout as a decimal marker. 1 The test method is intended for assessing the stength and deformation behaviour of sandwiches under tensile stress perpendicular to the faces. It is suitable for sandwiches of any structure and for any materials
3、 the core and the faces are made of and can also be used for testing the bonding between face and core. The properties of a sandwich which can be determined according to this standard are the Field of application and purpose tensile strength tensile stress at break yield stress tensile stress for a
4、specified strain stress for x % offset yield stress/deformation behaviour 2 Concepts See also DIN 53 290 Testing of sandwiches; concepts 2.1 The tensile stress o is the force F at any moment of the test referred to the initial cross section Ao of the specimen. 2.2 The tensile strengthuB of a sandwic
5、h is the tensile stress at the maximum tensile force F, (see figure 1). 2.3 The tensile stress at break uR is the tensile stress at the moment of break of the specimen. Note: The sandwich may break in the face, between face and core as well as in the core. The type of rupture must therefore always b
6、e quoted in the test report. 2.4 Yield stress us is the tensile stress at which the slope of the force/deformation curve equals O for the first time (see figure 1 ). 2.5 The tensile stress for a specified strain u, is the tensile stress correlated to a given strain c = x %. In the symbol u, the subs
7、cript x must be replaced by the nume- rical value of the percentage of compressive strain, e.g. alfor c = 2%. 2.6 The stress for x % offset yield usx is the tensile stress at which the force/deformation curve deviates by 3c % of the strain from its initially linear course (see figure 1). 2.7 The str
8、ain E is the change in specimen height ho related to the original height of the specimen A h includ- ing the faces at any time during the test. The strain at maximum force is designated E, the strain at ultimate force eR and the strain at yield stress cs. Continued on pages 2 to 4 Sole sale rights o
9、f German Standards (DIN-Normen) are with Beuth Verlag GmbH. Berlin 30 DIN 53 292 Engl. Price group 5 11.82 Cales No. O1 05 Page 2 DIN 53 292 2.8 A specimen within the meaning of this standard is a piece cut from a sheet of sandwich (see clause 5). 2.9 A test piece within the meaning of this standard
10、 is a specimen with load application blocks (see clause 7). AhR Change in height Ah - F, maximum force Fs force at yield stress FR force at rupture of the sandwich Fx force correlated to a given strain Fsx force at x % offset yield stress AhFmax change in height at maximum force Ahs change in height
11、 at yield stress Ahx change in height at a given strain Ahsx change in height corresponding to a given x % strain for determining Fsx AhR change in height at rupture of the sandwich Figure 1. Examples of force/deformation diagrams 3 Designation of the method Designation of the method to be applied i
12、n the tensile test (A) : Tensile test DIN 53 292 - A 4 Apparatus 4.1 Testing machine A class 1 tensile testing machine according to DIN 51 221 Part 1 must be used. The force measuring devices and force indicating devices shall have the lowest possible inertia. 4.2 Clamping device The clamping device
13、 must be designed in such a manner that the tensile force is applied to the metal blocks of the specimen without bending moment and so that the longitudinal axis of the specimen is free to adjust itself in the direction of the tensile force (for example of a clamping device, see figure 2). Pivot / t
14、 fa Bolt standard atmospheres Material testing machines; tensile testing machines; general requirements Testing of adhesives for metals and bonded metal joints; conditions for testing at differing temperatu res Testing of sandwiches; concepts Further standards DIN 50 145 DIN 51 221 Part 2 Testing of
15、 metallic materials: tensile test Material testing machines; large tensile testing machines and universal testing machines Previous editions DIN 53 292: 04.73,07.76 Amendments Compared with the July 1976 edition, the contents have been revised editorially. Explanations This standard was prepared by
16、Technical Committee NMP 456 “Testing of sandwiches“ of Normenausschuss Materialprfung (NMP) (Materials Testing Standards Committee). Some symbols in this standard are no longer in conformity with the symbols newly specified in DIN 50 145 Testing of metallic materials; tensile test, May 1975 edition. They have been retained so as to conform with other test standards for sandwiches and with the test standards for plastics.
