ISO/TR TECHNICAL REPORT 12998 First edition 2019-04 Mechanical joining Guidelines for fatigue testing of joints Assemblage mécanique - Lignes directrices pour les essais de fatigue des assemblages Reference number ISO/TR 12998:2019(E) Tso @IS02019 IS0/TR 12998:2019(E) COPYRIGHTPROTECTEDDOCUMENT @ IS0 2019 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either IsO at the address below or Iso's member body in the country of the requester. ISO copyright office CP 401 : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +41 22 749 01 11 Fax: +41 22 749 09 47 Email: [email protected] Website: www.iso.org Published in Switzerland ii @ IS0 2019 - All rights reserved IS0/TR 12998:2019(E) Contents Page Foreword ..V Introduction. ..vi 1 Scope. 2 Normative references 3 Terms and definitions 4 Symbols and abbreviated terms 5 Specimens ..6 5.1 General .6 5.2 Test specimen materials ..7 5.3 Types of test specimens ..8 5.4 Selection of suitable specimens 5.5 Test specimen fabrication. .10 5.5.1 Coupons for specimen fabrication 10 5.5.2 Bending and forming .10 5.5.3 Joining .11 5.5.4 Tolerances. ..11 5.5.5 Storage. ..11 5.5.6 Inspection ..11 5.6 Test specimen geometry .12 5.6.1 General. 5.6.2 Specimen geometry of tensile shear and peel specimens ..12 5.6.3 Geometry of the hat and other closed section specimens. ..18 5.6.4 Double disc and KS-2 specimen. .22 6 Specimen clamps and alignment. ..23 6.1 General 23 6.2 Verification and adjustment of specimen clamps and alignment 23 6.2.1 Alignment. 23 6.2.2 Verification of the clamping .23 6.3 Clamping device design 24 6.3.1 General .24 6.3.2 Example of suitable clamping device design 25 7 Testing procedure .26 7.1 General. 26 7.2 Testing machine 26 7.3 Mounting of clamping devices/clamps. 26 7.4 Clamping procedure. 26 7.5 Fatigue testing 27 7.5.1 General 27 7.5.2 Setting load conditions for the fatigue testing 28 7.5.3 Test frequency .30 7.6 Test termination .30 7.6.1 General 30 7.6.2 Failure criterion and number of cycles to failure 31 7.6.3 Stiffness. 32 7.6.4 Data acquisition. 32 7.7 Re-testing. ..33 8 Test report .33 8.1 Basic information. 33 8.1.1 General .33 8.1.2 Material prior to fatigue test specimen preparation .33 8.1.3 Mechanical properties ..33 @ IS0 2019 - All rights reserved ii