1、Subcritical Cracking of Modern 2Cr-1Mo-V Steel Due to Dissolved Internal Hydrogen and H2Environment, Research ReportAPI TECHNICAL REPORT 934-F, PART 3FIRST EDITION, DECEMBER 2017Subcritical Cracking of Modern 2Cr-1Mo-V Steel Due to Dissolved Internal Hydrogen and H2Environment, Research ReportAPI TE
2、CHNICAL REPORT 934-F, PART 3FIRST EDITION, DECEMBER 2017Prepared under contract for API by:Dr. Richard P. GangloffEmeritus Ferman W. Perry Professor of Materials Science and EngineeringDepartment of Materials Science and EngineeringSchool of Engineering and Applied ScienceUniversity of Virginia, Cha
3、rlottesville, VirginiaKevin Nibur, Ph.D., P.E.Hy-Performance Testing, LLC17676 Paladin DriveBend, OR 97701Sylvain PillotIndusteel, ArcelorMittal Group-Le Creusot Research Center56 Rue Clmenceau BP 19-F71201Le Creusot, Cedex, FranceSpecial NotesAPI publications necessarily address problems of a gener
4、al nature. With respect to particular circumstances, local,state, and federal laws and regulations should be reviewed.Neither API nor any of APIs employees, subcontractors, consultants, committees, or other assignees make anywarranty or representation, either express or implied, with respect to the
5、accuracy, completeness, or usefulness of theinformation contained herein, or assume any liability or responsibility for any use, or the results of such use, of anyinformation or process disclosed in this publication. Neither API nor any of APIs employees, subcontractors,consultants, or other assigne
6、es represent that use of this publication would not infringe upon privately owned rights.API publications may be used by anyone desiring to do so. Every effort has been made by the Institute to assure theaccuracy and reliability of the data contained in them; however, the Institute makes no represen
7、tation, warranty, orguarantee in connection with this publication and hereby expressly disclaims any liability or responsibility for loss ordamage resulting from its use or for the violation of any authorities having jurisdiction with which this publication mayconflict.API publications are published
8、 to facilitate the broad availability of proven, sound engineering and operatingpractices. These publications are not intended to obviate the need for applying sound engineering judgmentregarding when and where these publications should be utilized. The formulation and publication of API publication
9、sis not intended in any way to inhibit anyone from using any other practices.Any manufacturer marking equipment or materials in conformance with the marking requirements of an API standardis solely responsible for complying with all the applicable requirements of that standard. API does not represen
10、t,warrant, or guarantee that such products do in fact conform to the applicable API standard.Users of this technical report should not rely exclusively on the information contained in this document. Soundbusiness, scientific, engineering, and safety judgment should be used in employing the informati
11、on containedherein.All rights reserved. No part of this work may be reproduced, translated, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission from the publisher. Contact the Publisher, API Publis
12、hing Services, 1220 L Street, NW, Washington, DC 20005.Copyright 2017 American Petroleum InstituteForewordNothing contained in any API publication is to be construed as granting any right, by implication or otherwise, for themanufacture, sale, or use of any method, apparatus, or product covered by l
13、etters patent. Neither should anythingcontained in the publication be construed as insuring anyone against liability for infringement of letters patent.Questions concerning the interpretation of the content of this publication or comments and questions concerning theprocedures under which this publi
14、cation was developed should be directed in writing to the Director of Standards,American Petroleum Institute, 1220 L Street, NW, Washington, DC 20005. Requests for permission to reproduce ortranslate all or any part of the material published herein should also be addressed to the director.Generally,
15、 API standards are reviewed and revised, reaffirmed, or withdrawn at least every five years. A one-timeextension of up to two years may be added to this review cycle. Status of the publication can be ascertained from theAPI Standards Department, telephone (202) 682-8000. A catalog of API publication
16、s and materials is publishedannually by API, 1220 L Street, NW, Washington, DC 20005.Suggested revisions are invited and should be submitted to the Standards Department, API, 1220 L Street, NW,Washington, DC 20005, standardsapi.org.iiiContentsPageExecutive Summary . . . . . . . . . . . . . . . . . .
17、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xivBackground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Literature
18、 Review of Hydrogen Cracking in Cr-Mo-V Steel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Research Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
19、 4Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Experimental Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
20、 . . . . . . . . . . . . . . . . . . . . 4Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Discussion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
21、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136Annex ACr-Mo-V Base Plate Spec
22、ifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139Annex BCr-Mo-V Weld Metal Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140Bibliography . . . . . . . . . . . . .
23、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142Figures1 The effect of predissolved bulk total H concentration on KIHfor IHAC of several heats of modern low-impurity Cr-Mo base plate and weld metal stressed under
24、 slow-rising K at 23 C . . . . . . . . . . . . . . . . . . . 22 Welded test block of 2Cr-1Mo-0.27V steel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Welded test block geometry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 Autoclave assembly used for elevated-temperature H charging in a high-pressure H2environment . . . 85 The temperature dependence of the Sieverts law solubility coefficient for Cr-Mo and Cr-Mo-V steels . . . . . . . . . . . . . . . . .
26、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 The temperature dependence of the H diffusivity for Cr-Mo and Cr-Mo-V steels . . . . . . . . . . . . . . . . . . . 117 Results of an error analysis relating the concentration of dissolved H (top axis,
27、in wppm) and the mass of the steel specimen analyzed (vertical axis, gm) to the error index . . . . . . . . . . . . . . . . 138 C(T) specimen orientation in the welded blocks of 2Cr-1Mo-V steel . . . . . . . . . . . . . . . . . . . . . . . . . . 149 Instrumentation elements of the IHAC test method .
28、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1510 Compact tension specimen and associated probes for IHAC testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1611 Apparatus used for high-pressure H2testing of compact tension specimens . . . . . . .
29、 . . . . . . . . . . . . . . 1812 Time-dependent H loss during isothermal exposure of 2Cr-1Mo-0.30V base metal in moist air at 23 C and 100 C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2213 Time-dependent H loss during
30、isothermal exposure of 2Cr-1Mo-0.27V weld metal in moist air at 23 C and 100 C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2214 The temperature dependence of trap-sensitive effective H diffusivity (DH-Eff) for weld metal
31、 and base plate of the 2Cr-1Mo-0.3V steel used in this API study of IHAC. . . . . . . . . . . . . . . . . . . . . . . . 2315 R-curve based fracture toughness for step-cooled 2Cr-1Mo-0.3V base plate and weld metal at two loading temperatures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
32、. . . . . . . . . . . . . . . . . . . . . . . 24vContentsPage16 (Top) Load and DCPD vs CMOD, and (bottom) definition of the onset of stable crack propagation based on amplified DCPD vs CMOD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2517 Scanning electr
33、on fractographs showing ductile fracture in 2Cr-1Mo-0.3V base metal at 23 C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2618 Crack extension vs applied KJfor C(T) specimens of 2Cr-1Mo-
34、0.3V base metal, with and without precharged H . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2719 (Top left) DCPD vs CMOD and (bottom right) DCPD vs the J-integral to define the onset of crack extension at the indicate
35、d value of KIHfor specimen BM8A of 2Cr-1Mo-0.3V containing precharged H . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2820 (Top) Stretch zone in 2Cr-1Mo-0.3V base metal without H (BM2A), (bottom left) stretch zone ap
36、pearance in a base metal specimen with precharged H (BM8A), and (bottom right) stretch zone in a H-precharged specimen of weld metal (WMA4) . . . . . . . . . . . . . . . . . . . 2921 The slope of DCPD vs CMOD, prior to the onset of organized crack extension, is parallel for noncharged base metal, no
37、ncharged weld metal, and H-precharged base metal at 26 C and 40 C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3022 Measured DCPD vs CMOD (top) and calculated crack length from Johnsons equation vs CMOD
38、(bottom), using the first deviation in DCPDCMOD linearity as the onset of crack extension for specimen BM6A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3223 Measured DCPD vs CMOD (top) and calculated crack length from Johnsons equatio
39、n vs CMOD (bottom), using the first deviation in DCPDCMOD linearity as the onset of crack extension for specimen BM10A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3324 SEM fractographs of the zones of stretch and stable cracking ahead o
40、f the fatigue precrack shown in the bottom half of each image for: (top) BM6A and (bottom) BM10A . . . . . . . . . . . . . . . . . . . . 3425 Measured DCPD vs CMOD (top) and calculated crack length from Johnsons equation vs CMOD (bottom), using the first deviation in DCPDCMOD linearity as the onset
41、of crack extension for specimen BM4A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3626 SEM fractograph of the zones of fatigue precrack (bottom arrow), stretch/H cracking (middle arrow), and post-test cleavage (top arrow) specimen BM4A
42、 . . . . . . . . . . . . . . . . . . . . . 3727 Measured DCPD vs CMOD (top) and SEM fractograph for specimen BM11A . . . . . . . . . . . . . . . . . . . . . . 3828 Measured DCPD vs CMOD (top) and SEM fractograph for weld metal specimen WMC4. . . . . . . . . . . . . 4029 Measured DCPD vs CMOD (top) a
43、nd calculated crack length from Johnsons equation vs CMOD (bottom), using the indicated deviation in DCPDCMOD linearity as the onset of crack extension for specimen WMD3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4130 SEM fractograph of the three zo
44、nes of cracking observed in the interrupted loading experiment with H-precharged weld metal specimen WMD3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4231 Macrophotographs of the fracture surfaces for interrupted specimens of Cr-Mo-V steel . . . . . . . . . . . . 4232 Measured DCPD vs C
45、MOD (top) and calculated crack length from Johnsons equation vs CMOD (bottom) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4333 Composite SEM fractographs of the fracture surface from specimen BM12-3
46、 . . . . . . . . . . . . . . . . . . . . . 44viContentsPage34 Macrophotographs of 2Cr-1Mo-0.30V base metal compact tension specimens that were fatigue precracked, H-precharged, stressed under slow-rising K in moist air, unloaded, and fractured in liquid nitrogen . . . . . . . . . . . . . . . . . . .
47、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4835 (Top) Load and DCPD vs CMOD. (Middle) Amplified definition of the onset of crack propagation using the defined departure in linear DCPD vs CMOD at the resulting value of KIH.(Bottom) Crack growth resistance curve
48、, given as the amount of stable crack growth vs applied elastic-plastic K . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 495036 Crack growth resistance curves, plotted as the elastic-plastic stress intensity factor vs crack ext
49、ension from DCPD, for H-precharged 2Cr-1Mo-0.3V base metal stressed under slow-rising K at 26 C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5137 Macrophotograph of the fracture surface of 2Cr-1Mo-0.3V base metal specimen BM8A, showing the fatigue precrack (bottom flat region), IHAC region (middle roughened features), and liquid nitrogen cleavage region (top) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5238 Sca
