BS ISO 17340:2014 pdf free

BS ISO 17340:2014 pdf free.Metallic materials一Ductility testing一High speed compression test for porous and cellular metals
This test consists of applying an impact force at test speeds between 0,1 m/s and 100 m/s to porous and cellular metals and measuring the compressive force and displacement for evaluation of their high-speed compressive deformation characteristics, such as plateau stress and energy absorption. Test methods that apply high-speed compressive forces to porous and cellular metals are the drop weight impact test and the servo-type high-speed compression test.
The drop weight impact test applies the compressive force by dropping a weight from a specified height.The test speed is controlled by the drop height. Due attention should be paid to the fact that the weight will be decelerated during the period of compressive deformation. When the drop height necessary to reach the specified test speed cannot be obtained, application of an initial velocity to the weight is possible.
The servo-type high-speed compression test applies the compressive force using a hydraulic or electric high-speed servo mechanism. The test speed is changed by the servo control. The drive unit shall be capable of following the test speed.
The pressing jigs are located above and below the test piece and are used to apply the compressive force to the test piece. The pressing jig shall be of a construction such that it does not deform due to the compressive force, allowing correct transmission of the compressive force in the axial direction and preventing the action of forces, such as bending stress, etc., other than the compressive force on the test piece.
The area of the pressing surfaces shall be sufficiently large to ensure an even application of the compressive force over the entire end surface of the test piece until compressive deformation is complete. The pressing surfaces shall be polished flat and installed in such a manner that the centre of the planes is aligned with the centre line of the testing machine and the planes are parallel to each other.BS ISO 17340 pdf free download.