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Kommittébeteckning: SIS/TK 133 (Pulvermetallurgi)
Källa: ISO
Svarsdatum: den 10 mar 2020
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This International Standard specifies a generic test method to determine the abrasion wear characteristics of hardmetals.

The procedure complements the ASTM G65 method for dry sand/rubber wheel abrasion, the ASTM B611 method for determining the high stress abrasion of hard materials, and the ASTM G105 method for conducting wet sand/rubber wheel abrasion tests.

The test is appropriate for use in situations where test laboratories have a need to simulate abrasive damage. The procedure includes information which enables the test to be used in a variety of different conditions:

a) with counterface wheels of different stiffness (for example steel and rubber);

b) wet and dry;

c) different abrasive sizes;

d) different chemical environments.

Kommittébeteckning: SIS/TK 123 (Mekanisk provning)
Källa: ISO
Svarsdatum: den 28 mar 2020
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This International Standard specifies the conditions for conducting plane bending fatigue test on axial machine, constant-amplitude, force or displacement controlled, at room temperature (ideally between 10°C and 35°C) on metallic specimens, without deliberately introduced stress concentrations. This International standard does not include reversed/partially loading test. The purpose of test while using this International Standard is to provide relevant results, such as the relation between applied stress and number of cycles to failure for a given material condition, expressed by hardness and microstructure, at various stress ratios.

Although the shape, preparation and testing of specimens of rectangular and beveled cross-section are specified; component testing and other specialized forms of testing are not included in this International Standard.

NOTE 1 Fatigue tests on notched specimens are not covered by this International Standard since the shape and size of notched test pieces have not been specified in any standard so far. Guidelines are given in Annex A. However, it is permitted to use the fatigue-test procedures described in this standard for testing of such notched specimens.

NOTE 2 There is a possibility of getting the results of a fatigue test be affected by atmospheric conditions, and where controlled conditions are required, subclause 2.1 of ISO 554 applies.

Kommittébeteckning: SIS/TK 123 (Mekanisk provning)
Källa: ISO
Svarsdatum: den 10 apr 2020
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This document specifies methods for determining fracture toughness in terms of K, δ, J and R-curves for homogeneous metallic materials subjected to quasistatic loading. Specimens are notched, precracked by fatigue and tested under slowly increasing displacement. The fracture toughness is determined for individual specimens at or after the onset of ductile crack extension or at the onset of ductile crack instability or unstable crack extension. In some cases in the testing of ferritic materials, unstable crack extension can occur by cleavage or ductile crack initiation and growth, interrupted by cleavage extension. The fracture toughness at crack arrest is not covered by this document. In cases where cracks grow in a stable manner under ductile tearing conditions, a resistance curve describing fracture toughness as a function of crack extension is measured. In most cases, statistical variability of the results is modest and reporting the average of three or more test results is acceptable. In cases of cleavage fracture of ferritic materials in the ductile-to-brittle transition region, variability can be large and additional tests may be required to quantify statistical variability. Special testing requirements and analysis procedures are necessary when testing weldments and these are described in ISO 15653[1] which is complementary to this document.

When fracture occurs by cleavage or when cleavage is preceded by limited ductile crack extension, it may be useful to establish the reference temperature for the material by conducting testing and analysis in accordance with ASTM E1921.[2]