ISO INTERNATIONAL STANDARD 3327 Third edition 2009-05-15 Hardmetals Determination of transverse rupture strength Metaux-durs - Détermination de la resistance a la flexion Reference number ISO 3327:2009(E) @ ISO 2009 ISO 3327:2009(E) Foreword IsO (the International Organization for Standardization) is a worldwide federation of national standards bodies (IsO member bodies). The work of preparing International Standards is normally carried out through IsO non-governmental, in liaison with isO, also take part in the work. isO collaborates closely with the InternationalElectrotechnicalCommission(lEC)onallmattersofelectrotechnicalstandardization. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. rights. IsO shall not be held responsible for identifying any or all such patent rights. ISO 3327 was prepared by Technical Committee ISO/TC 119, Powder metallurgy, Subcommittee SC 4, Sampling and testing methods for hardmetals. This third edition cancels and replaces the second edition (IsO 3327:1982), which has been technically revised. @ IS0 2009 - All rights reserved ili INTERNATIONAL STANDARD ISO3327:2009(E) Hardmetals Determination of transverse rupture strength 1 Scope This International Standard specifies a method for the determination of the transverse rupture strength of hardmetals. Thismethodis applicabletohardmetalsof negligible ductility.If itis usedforhardmetals showingsignificant plasticdeformationbeforebreaking,incorrectresultsmaybeobtained.Insuchcases,themethodmaybe used for comparison purposes only. 2 Symbols and designations Table 1 Symbols and designations Symbol Designation Unit F Force required to fracture the test piece N 1 Distance between supports mm b Width of test piece perpendicular to its height mm h Height of test piece parallel to the direction of application of the test force mm k Correction factor to compensate for the chamfer Ra Surface roughness μm Rbm Transverse rupture strength N/mm2 d Diameter of test piece (if a cylindrical test piece is used) mm 3 Principle Breakingatestpiecelyingfreelyontwosupportsbyapplicationofaforceatthemidpointofthespan,under conditions of short-term static application of the force. 4 Apparatus 4.1 Device for applying a force, capable of applying a uniformly increasing force with an accuracy of 1 % or better. 4.2 Three cylinders (rollers), of which two are freely lying support cylinders with a fixed distance between them and one is a freely lying force cylinder. The three cylinders shall be of equal diameter between 3,2 mm and 6 mm. @ ISO 2009 - All rights reserved 1