ISO 22889:2013 pdf free
ISO 22889:2013 pdf free.Metallic materials – Method of test for the determination of resistance to stable crack extension using specimens of low constraint
The resistance to stable crack extension of metallic materials can be characterized in terms of either specific (single point) values (see Annex D) or a continuous curve relating fracture resistance to crack extension over a limited range of crack extension (see Clause 6). Any one of the fatigue-cracked test specimen configurations specified in this method may be used to measure or calculate any of these fracture resistance parameters. Tests are performed by applying slowly increasing displacement to the test specimen and measuring the resulting force and corresponding crack opening displacement and angle. The measured forces, displacements and angles are then used in conjunction with certain pre-test and post-test specimen measurements to determine the material’s resistance to crack extension. Details of test specimens and general information relevant to the determination of all fracture parameters are given in this method. A flow-chart illustrating the way this International Standard can be used is presented in Figure 1.
It is recommended that anti-buckling plates be attached to both sides of the tension specimen covering the expected path of the crack for a distance four times the initial total crack length perpendicular to the crack. Frictional forces between the specimen and anti-buckling plates shall be minimized by the use of an inert lubricant such as polytetrafluoroethylene (PTFE) applied to the mating surfaces. An access hole is required in one of the plates for mounting the δ5 gauge on the specimen or, if the potential method is used, for the attachment of cables.
The fixture shall be designed to distribute the load uniformly over the cross-section of the specimen.The fixture may be rigidly connected to the machine if uniform loading of the specimen in the machine can be ensured at all loads. Otherwise, pinloading via detachable grips is recommended.ISO 22889 pdf download.