ISO/TR TECHNICAL REPORT 12112 First edition 2018-04 Metallic materials Principles and designs for multiaxial fatigue testing Materiaux métalliques - Principes et conceptions associés aux essais de fatigue multiaxiale Reference number ISO/TR 12112:2018(E) osi @IS02018 IS0/TR 12112:2018(E) COPYRIGHTPROTECTEDDOCUMENT @ IS0 2018 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 2018 - All rights reserved IS0/TR 12112:2018(E) Contents Page Foreword ..V Introduction. ...vi 1 Scope. 2 Normative references 3 Terms and definitions 4 General principles. ..2 4.1 Methodology .2 2 4.2 Historical development. 4.3 Specific multiaxial test methods .6 4.3.1 Bending + torsion[6] ..6 4.3.2 Axial + torsion[Z] .6 4.3.3 Axial + internal pressure[8] ..6 4.3.4 Axial + internal + external pressure[9] .6 4.3.5 Axial + internal + external pressure + torsion[10] ..6 4.3.6 Cruciform — LCF[11] .6 4.3.7 Cruciform — Crack growth[12] .7 4.4 Multiaxial fatigue analysis ..7 4.4.1 Computer aided design .7 4.4.2 Fatigue life prediction. 4.5 Multiaxial fatigue failure criteria. ..8 5 Axial + torsion testing systems and specimen design ..9 5.1 Historical development. 5.2 Specimen design. .11 5.2.1 Design considerations .11 5.2.2 Design recommendations ..11 5.2.3 Comparison with ASTM E2207[4] .11 5.3 Machine design. ..12 5.3.1 Frame. .12 5.3.2 Loadcells. .12 5.3.3 Strain measurement. .12 5.3.4 Control ..12 5.3.5 Data acquisition. ..12 5.3.6 Software 12 6 Cruciform testing systems and specimen design ..13 6.1 Historical development ..13 6.2 Specimen design ..13 6.3 Machine design. .14 6.3.1 Frame. ..14 6.3.2 Loadcells. ..14 6.3.3 Strain measurement. ..15 6.3.4 Crack growth monitoring .15 6.3.5 Control .15 6.3.6 Data acquisition. ..15 6.3.7 Software .. 15 7 Axial + differential pressure systems and specimen design ..16 7.1 Historical development ..16 7.2 Specimen design.. ..19 7.2.1 Design considerations .19 7.2.2 Design recommendations .19 7.2.3 Axial stress due to pressure .20 7.3 Machine design. ..20 7.3.1 Frame. 20 @ IS0 2018 - All rights reserved ii