Astm stp 1406 2002

STP 1406 Fatigue and Fracture Mechanics: 32nd Volume Ravinder Chona, editor ASTM Stock Number: STP1406 ASTM 100 Barr Harbor Drive PO Box C700 West Conshohocken, PA 19428-2959 Printed in the U.S.A Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized ISBN: 0-8031-2888-6 ISSN: 1040-3094 Copyright 2002 AMERICAN SOCIETY FOR TESTING AND MATERIALS, West Conshohocken, PA All rights reserved This material may not be reproduced or copied, m whole or in part, tn any prmted, mechanical, electrontc, film, or other distributton and storage media, without the written consent of the publisher Photocopy Rights Authorization to photocopy items for internal, personal, or educational classroom use, or the internal, personal, or educational classroom use of specific clients, is granted by the American Society for Testing and Materials (ASTM) provided that the appropriate fee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, Tel: 978-750-8400; online: http:llwww,copyright.coml Peer Review Policy Each paper published in this volume was evaluated by two peer reviewers and at least on editor The authors addressed all of the reviewers' comments to the satisfaction of both the technical editor(s) and the ASTM Committee on Publications The quahty of the papers in this publication reflects not only the obvious efforts of the authors and the technical edttor(s), but also the work of the peer reviewers In keeping with long-standing publicatton practices, ASTM maintains the anonymity of the peer reviewers The ASTM Committee on Publications acknowledges wtth appreciation thetr dedicatton and contribution of time and effort on behalf of ASTM Printed in Brtdgeport,NJ September2001 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized Foreword This publication, Fatigue and Fracture Mechanics: 32nd Volume, contains papers presented at the symposium of the same name held at ASTM Headquarters, West Conshohocken, Pennsylvania, on 14-16 June 2000 The symposium was sponsored by ASTM Committee E-8 oD Fatigue and Fracture and was chaired by Dr Ravinder Chona of Texas A & M University Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authoriz Contents TRANSITION ISSUES AND MASTER CURVES M i c r o s t r u c t u r a l L i m i t s o f A p p l i c a b i l i t y o f t h e M a s t e r C u r v e - - - M T KIRK, M E NATISHAN, AND M WAGENHOFER C o r r e l a t i o n B e t w e e n S t a t i c I n i t i a t i o n T o u g h n e s s Kjc a n d C r a c k A r r e s t T o u g h n e s s Kin 2 - T A l u m i n u m A l l o y - - K WALLIN 17 NORMALIZATION PROCEDURES A S e n s i t i v i t y S t u d y o n a N o r m a l i z a t i o n P r o c e d u r e - - - w A VAN DER SLUYS AND B A YOUNG S e p a r a b i l i t y P r o p e r t y a n d L o a d N o r m a l i z a t i o n i n A A 6 - T A l u m i n u m A l l o y - - A N CASSANELLI, H ORTIZ, J E WAINSTEIN, AND L A DEVEDIA 37 49 FATIGUE P h y s i c a l R e a s o n s f o r a R e d u c e d A K as C o r r e l a t i o n f o r F a t i g u e C r a c k P r o p a g a t i o n - - - c MARCI AND M LANG Influence of Specimen Geometry on the Random Load Fatigue Crack G r o w t h - - J c RADON AND K NIKBIN F a t i g u e B e h a v i o r o f S A 3 - B S t e d s - - j - Y HUANG, R.-Z LI, K.-F cnmN, R.-C KUO, P K LIAW, B YANG, AND J.-G HUANG Scanning Atomic-Force Microscopy on Initiation and Growth Behavior of Fatigue S l i p - B a n d s in ~ - B r a s s - - Y NAKAI, T KUSUKAWA, AND N HAYASHI 75 88 105 122 DYNAMIC LOADING -PART ] C o m p l i a n c e R a t i o M e t h o d o f E s t i m a t i n g C r a c k L e n g t h in D y n a m i c F r a c t u r e T o u g h n e s s T e s t s - - J A JOYCE, P ALBRECHT, H C TJIANG, AND W J WRIGHT D y n a m i c F r a c t u r e T o u g h n e s s T e s t i n g a n d A n a l y s i s o f H Y - 0 W e l d s - - - s M GRAHAM , 139 158 WELDS AND CLADDING C r e e p C r a c k G r o w t h i n X C r M o V 12 Steel W e l d J o i n t s - - K s Kn~, N W LEE, Y K CHUNG, AND J J PARK A p p l i c a t i o n o f t h e L o c a l A p p r o a c h to F r a c t u r e in t h e B r i t t l e - t o - D u c t i l e T r a n s i t i o n R e g i o n o f M i s m a t c h e d W e l d s - - F MINAMI, T KATOU, AND H JING An X-Specimen Test for Determination of Thin-Walled Tube Fracture T o u g h n e s s - - H H HSU, K F CHIEN, H C CHU, R C KUO, AND P K LIAW 179 195 214 APPLICATIONS A n E n e r g e t i c A p p r o a c h f o r L a r g e D u c t i l e C r a c k G r o w t h in C o m p o n e n t s - - - s CHAPULIOT, S MARIE, AND D MOULIN 229 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions auth vi CONTENTS Prediction of Residual Stress Effects on Fracture Instability Using the Local Approach Y YAMASHITA,K SAKANO,M ONOZUKAAND F MINAMI 247 ANALYTICAL ASPECTS Advantages of the Concise K and Compliance Formats in Fracture Mechanics Calculations J R DONOSO AND J D LANDES Three-Dimensional Analyses of Crack-Tip-Opening Angles and ~5-Resistance Curves for 2024-T351 Aluminum Alloy M A JAMES,J C NEWMAN,JR., AND W M JOHNSTON, JR 263 279 COMPOSITES AND CERAMICS Modeling Multilayer Damage in Composite Laminates Under Static and Fatigue Load c SOUTISANDM KASHTALYAN Development of ASTM C 1421-99 Standard Test Methods for Determination of Fracture Toughness of Advanced Ceramics L BAR-ON,G D QUINN,J SALEM,AND M J JENKINS 301 315 Standard Reference Material 2100: Fracture Toughness of Ceramics -G o QUINN, K XU, R GETTINGS, J A SALEM, AND J J SWAB 336 SURFACE FLAWS Use of K1c and Constraint to Predict Load and Location for Initiation of Crack Growth in Specimens Containing Part-Through Cracks w G REUTER, J C NEWMAN, JR., J D SKINNER, M E MEAR, AND W R LLOYD An Experimental Study of the Growth of Surface Flaws Under Cyclic Loading v MCDONALD, JR AND S R DANIEWICZ 353 381 DYNAMIC L O A D I N G - - P A R T I I Development of Mechanical Properties Database of A285 Steel for Structural Analysis of Waste Tanks A J DUNCAN, K H SUBRAMANIAN, R L S1NDELAR, K MILLER A P REYNOLDS, AND Y J CHAO Indexes 399 411 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized Transition Issues and Master Curves Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No furth Mark T Kirk, MarjorieAnn E Natishan, and Matthew Wagenhofer Microstructural Limits of Applicability of the Master Curve REFERENCE: Kirk, M T., Natishan, M E., and Wagenhofer, M., "Microstructural Limits of Applicability of the Master Curve," Fatigue and Fracture Mechanics: 32nd Volume, ASTM STP 1406, R Chona, Ed., American Society for Testing and Materials, West Conshohocken, PA, 2001, pp 1-16 ABSTRACT: ASTM Standard Test Method E 1921-97, "Test Method for the Determination of Reference Temperature, To, for Ferritlc Steels in the Transition Range, addresses determination of To, a fracture toughness reference temperature for ferritic steels having yield strength ranging from 275 to 825 MPa E 1921 defines a ferritic steel as: "Carbon and low-alloy steels, and higher alloy steels, with the exception of austenitic stainless steels, martensitic, and precipitation hardened steels All ferritic steels have body centered cubic crystal structures that display ductile to cleavage transition temperature This definition is not intended to imply that all of the many possible types of ferritlc steels have been verified as being amenable to analysis by this test method." The equivocation provided by the final sentence was introduced due to lack of direct empirical evidence (i.e., fracture toughness data) demonstrating Master Curve applicability for all ferritic alloys m all heat treatment/irradiation conditions of interest This question regarding the steels to which E 1921 applies inhibits its widespread application for it suggests that the user should perform some experimental confirmation of Master Curve applicability before it is applied to a new, or previously untested, ferritic steel Such confirmations are, in many cases, either impractical to perform (due to considerations of time and/or economy) or imposslble to perform (due to material unavailability) In this paper we propose an alternative to experimental demonstration to establish the steels to which the Master Curve and, consequently, ASTM Standard Test Method E 1921 applies Based on dislocation mechanics considerations we demonstrate that the temperature dependency of fracture toughness in the fracture mode transition region depends only on the short-range bamers to dislocation motion established by the lattice structure (body-centered cubic (BCC) in the case of ferritic steels) Other factors that vary with steel composition, heat treatment, and irradiation include grain size/boundaries, point defects, inclusions, precipitates, and dislocation substructures These all provide long-range barriers to dislocation motion, and so influence the position of the transition curve on the temperature axis (i.e., To as determined by E 1921-97), but not its shape This understanding suggests that the myriad of metallurgical factors that can influence absolute strength and toughness values exert no control over the form of the variation of toughness with temperature In fracture mode transition Moreover, this understanding provides a theoretical basis to establish, a priori, those steels to which the Master Curve should apply, and those to which it should not On this basis, the Master Curve should model the transition fracture toughness behavior of all steels having an Iron BCC lattice structure (e.g., pearlitic steels, ferritic steels, balnitic steels, and tempered martensitic steels) Conversely, the Master Curve should not apply to untempered martensitic steels, which have a body-centered tetragonal (BCT) lattice structure, or to austenite, which has a FCC structure We confirm these expectatmns using experimental strength and toughness data drawn from the literature KEYWORDS: Master Curve, fracture toughness transition behavior, To, martensitic steel, ferritic steel, dislocation mechanics, nuclear reactor pressure vessels Semor materials engineer, United States Nuclear Regulatory Commission, Rockville, MD, 20852 Senior materials engineer, Phoenix Engineering Associates, Inc., 3300 Royale Glen Ave., Davidsonville, MD, 21035 Graduate research assistant, Mechanical Engineering Department, Umversity of Maryland, College Park, MD 20742 Copyright by ASTM Int'l (all rights reserved); Tue Dec 315 13:10:18 EST 2015 Downloaded/printed Copyright9 byby ASTM International www.astm.org University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized FATIGUE AND FRACTURE MECHANICS: 32ND VOLUME Background and Objective The Master Curve concept, as introduced by Wallin and co-workers in the mid-1980s, describes the fracture toughness transition of ferritic steels [1,2] The concept includes a weakest-link failure model that describes the distribution of fracture toughness values at a fixed temperature, and provides a methodology to account for the effect of crack front length on fracture toughness Additionally, Wallin observed that the increase of fracture toughness with increasing temperature is not sensitive to steel alloying, heat treatment, or irradiation [3,4] This observation led to the concept of a universal curve shape applicable to all ferritic steels Several investigators have empirically assessed the validity of a universal curve shape for both unirradiated and irradiated nuclear reactor pressure vessel (RPV) steels, invariably with favorable results [5,6] These research and development activities have led to passage of an ASTM Standard Test Method E 1921-97 to estimate the Master Curve index temperature (To) [7], and to adoption of a Code Case (N-629) within ASME Section XI that uses To to estabhsh an index temperature (RTro) for the Kic and KI~ curves [8] The strong empirical evidence supporting a Master Curve for nuclear RPV steels, and it's acceptance into consensus codes and standards, sets the scene for its application to assessment of nuclear RPV integrity to end of license (EOL) and beyond [9] However, as with any empirical methodology, questions arise regarding the appropriateness of the technique beyond its data basis [10] Favorable resolution of this question is especially important in nuclear RPV applications, where it is not always possible to conduct tests on the steel that most hmits reactor operations Recent work by Natishan and co-workers has focused on development of a physical basis for a universal Master Curve shape that would enable one to establish, a priori, those steels to which the Master Curve should apply, and those to which it should not [11-13] These investigators employ dislocation-based deformation models to describe how various aspects of the microstructure of a material control dislocation motion, and thus the energy absorbed to fracture, and how these effects vary with temperature and strain rate The microstructural characteristics of interest include both short- and long-range barriers to dislocation motion: Short Range Barriers: The lattice itself provides short-range barriers that effect the atom-toatom movement required for a dislocation to change position within the lattice Long Range Barriers: Long-range barriers include point defects (solute and vacancies), precipitates (semicoherent to noncoherent), boundaries (twin, grain, etc.), and other dislocations Long-range barriers have an inter-barrier spacing several orders of magnitude greater than the short-range barriers provided by the lattice spacing Classifying microstructural features by their inter-barrier spacing is key to establishing the microstructural features responsible for the temperature dependency of the flow behavior, and thus for the shape of the Master Curve Thermal energy acts to increase the amplitude of vibration of atoms about their lattice sites, consequently increasing the frequency with which an atom is out of its equilibrium position in the lattice Since the activation energy for dislocation motion depends on the energy needed to move one atom past another, this energy is reduced when an atom is out of position Increased thermal energy therefore decreases the resistance of these short-range lattice barriers to dislocation motion Conversely, increased thermal energy is not effective at moving dislocations past long-range obstacles because no matter how large the amplitude of atomic vibration, the height of the energy barrier required to move the dislocation past these large obstacles is orders of magnitude larger The flow stress of a material includes contributions from both the thermally activated shortrange barriers to dislocation motion, as well as from the nonthermally activated long-range barriers In their work, Natishan and co-workers demonstrate that the temperature dependency of the Master Curve depends only on the short-range barriers to dislocation motion This finding suggests that the only criterion for Master Curve applicability is the existence of the body-centered cubic (BCC) Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authoriz KIRK ET AL ON APPLICABILITY OF THE MASTER CURVE iron lattice structure characteristic of ferritic steels In this study, we use this physical understanding to identify steels both at and beyond the bounds of Master Curve applicability We assemble fracture toughness and strength data for these steels from the literature to validate these predictions The steels examined vary over a large range of composition and heat-treatment relative to that characteristic of RPV steels As such, this study addresses concerns about extrapolation of the Master Curve beyond its empirical basis by demonstrating that an understanding of the physics underlying the Master Curve can be used to establish the steels it applies to without the need for empirical demonstration Limits of Master Curve Applicability Based on Dislocation Mechanics Considerations In their 1984 paper, Wallin, Saario, and T~Srrrnen (WST) [3] suggest a link between the micro-mechanics of cleavage fracture and the observation of a "master" fracture toughness transition curve WST use a modified Griffith equation to define the fracture stress, i.e., 7rE'yeff 2(1 - v2)ro t~f~11= ( 1) Where E v ro Yeff is the elastic modulus is Poisson's ratio is the size of the fracture-cansing microstructural feature, and is the effective surface energy of the material, i.e., the sum of the surface energy and the plastic work absorbed to crack initiation (% + Wp) In the transition region, Yeffis dominated by the plastic work consumed in moving dislocations WST showed that values of Kit computed based on a temperature dependent expression for the plastic work fit experimental KI, values much more accurately than K1,, values calculated using a temperature independent %ff value of 14 J/m [14,15] WST proposed the following empirically motivated temperature dependence of wp wp = A + B " exp[C " T] (2) Natishan and Kirk [11] proposed that the empiricism represented by Eq is unnecessary, and provided the following dislocation-mechanics based description of the plastic work term "~eff = fade 9e (3) Here the integrand is a measure of the strain energy density, and f is the length scale ahead of the crack over which this strain energy density is applied The choice of a constitutive model based on dislocation mechanics to define the stress value in Eq establishes a physically based method of computing fracture toughness while simultaneously accounting for the uniform temperature dependence of fracture toughness for ferritic steels These investigators used the following constitutive model derived by Zerilli and Armstrong based on dislocation mechanics considerations [16] k ITZ_ A = mcr~ q- ~ + C e n -]- C e x p [ - C T + C4T" In(k)] (4) Vl Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized 400 FATIGUE AND FRACTURE MECHANICS: 32ND VOLUME the fracture properties The subject fracture properties were determined from J-R curves that conformed to ASTM Standard Test Method for Measurement of Fracture Toughness (E 1820) [3] Test Matrix A285 carbon steel demonstrates a wide variation of fracture properties depending on composition, microstructure, orientation, and other factors [4,5] An understanding of the quantitative effects of these factors on ductile tearing will enhance the ability to perform material-specific flaw stability analyses to improve the accuracy of operational limits To achieve that goal, a statistically designed test program was employed to investigate the impact of composition, orientation, and microstructure on the fracture properties of A285 carbon steels Variables were defined at levels relevant to the material and test conditions applicable to the waste storage tanks Several heats of A285 steel were acquired with a variety of compositions and plate thicknesses A total of 12 heats were acquired to make up the test matrix, which span the compositional range shown in Table The specific compositions of three heats tested are also included in Table I along with grain size and yield strengths from the materials certificate A quadratic model, based on the test parameters to be investigated was developed and a statistically designed test matrix was generated in order to predict mechanical properties as function of composition, microstructure, geometry, loading rate, and temperature The resultant matrix provided over 100 trials for the measurement of mechanical properties as function of the variables The mechanical properties of primary interest are: (1) fracture toughness, and (2) tensile properties In this study, the initial 15 fracture toughness tests are reported along with preliminary observations and data analysis Experimental variables of this initial portion of the test matrix, shown in Table 2, included thickness, orientation, and temperature Property Database A mechanical properties database is needed to perform flaw stability analyses for waste tanks at SRS Elastic-plastic fracture mechanics methodologies, with a ductile tearing instability criterion were used to develop a materials-specific database of fracture properties J-Integral toughness testing was used to compile material J-R curves and determine J energy at a specified crack length of mm Statistical confidence intervals were compiled for J3mmvalues of samples tested under similar conditions Jlc was also determined from the power law fit of the J-R curves for comparison Testing Methods Microstructural Analysis Samples were characterized using optical metallography Ferrite grain sizes were measured in each orientation using the linear intercept method in accordance with ASTM Test Methods for Determin- TABLE Compositlons, grain size, and yield strengths of selected heats Heat C (wt%) Mn (wt%) P (wt%) S (wt%) Grain (/xm) o-y, (MPa) A285" E400 1A434 382835 0.05-0.023 0.18 0.082 0.15 0.35-0.9 0.43 0.676 0.84 0.005-0.035 0.009 0.017 0.005 0.005-0.032 0.026 0.011 0.012 51.2 52.1 50.6 290 317 308 * Range of compositions considered for study Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized DUNCAN ET AL ON ANALYSIS OF WASTE TANKS 401 TABLE Test matrix and test conditions Heat E400 E400 E400 E400 E400 E400 E400 E400 E400 E400 E400 E400 E400 1A434 382835 Sample Thickness (mm) Side Groove, % Temp (K) Orient L1 L2 L3 L4 L6 L8 L9 L10 T1 T2 T3 T4 T5 15 12.7 12.7 15.2 15.2 15.2 15.2 15.2 15.2 12.7 12.7 15.2 15.2 15.2 22.2 19.0 10 10 10 10 20 20 20 10 10 10 10 20 10 10 294 294 296 296 297 295 294 294 294 300 298 297 300 288 288 L-T L-T L-T L-T L-T L-T L-T L-T T-L T-L T-L T-L T-L T-L T-L ing Average Grain Size Using Semiautomatic and Automatic Image Analysis (E 1382) [6] The grain size reported is averaged over three orientations Fracture surfaces were analyzed using scanning electron microscopy Specimen Design Fracture toughness was determined using compact tension specimens of ASTM standard geometry shown in Fig The specimens were machined in nominal configuration for a specimen of varying thickness (B) from 12.7 to 22.2 mm The nominal specimen width (W) of 63.5 m m was chosen in order to allow for measurement of valid J at large crack extensions, in accordance with ASTM E 1820 However, the thickness was not increased for two reasons: (1) thickness was limited to the maximum section thickness of the storage tanks, 22.2 mm; (2) many of the heats available for testing have a maximum plate thickness of less than 20 ram Testing Fracture toughness tests were conducted to obtain J-R curves for each of the specimens, as prescribed by ASTM E 1820 Crack length measurements were made either by Direct Current Potential Drop (DCPD) or unloading compliance (UC) All tests were performed corresponding to a stress intensity loading rate of 8.2 • 10 (MPa_X/~m)/s The load line crack opening displacement was measured with an inboard clip gage attached to front notches at the load line After testing, optical crack length measurements were made and used to transcribe experimental crack length data according to ASTM E 1820 The transcribed crack length data were used to calculate J deformation (Jdef) in accordance with ASTM E 1820 Results and Discussion Microstructures The microstructure of each heat consisted of ferrite grains with intergranular pearlite All three of the heats exhibited banding of pearlite (shown in Fig 2) to some degree, typical of hot rolled plate steel This condition has been attributed to manganese segregation in steels, but also may be caused by precipitation of non-metallic inclusions or hot rolling at low finishing temperatures and cooling Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions author 402 FATIGUE AND FRACTURE MECHANICS: 32ND VOLUME FIG Nominal compact tension specimen design FIG Example of pearlite bands observed in heat E400 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized DUNCAN ET AL ON ANALYSIS OF WASTE TANKS 403 rates [7] The effects of banding and/or inclusions on mechanical properties can vary depending on orientation, morphology and continuity In general, the presence of banding has been observed to decrease Charpy upper shelf fracture energy and decrease the ductile to brittle transition temperature in Charpy impact tests [8] The microstructures on three orthogonal planes of all three heats (E400, 382835, and 1A434) are shown in Fig 3a, b and c Figure illustrates fracture surface variability of these steels with respect to testing orientation in a single heat Figure 4a shows the fracture surface of an E400 specimen in the T-L orientation De- FIG Microstructure of heats: a) E400, b) 382835 and c) 1A434 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized 404 FATIGUE AND FRACTURE MECHANICS: 32ND VOLUME a) b) FIG SEM micrograph of the fracture surfaces of E400 C(T) specimens in the a) T-L and b) L-T orientations Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized DUNCAN ET AL ON ANALYSIS OF WASTE TANKS 405 laminations, coincidental with pearlite bands, divide the crack plane similar to a crack divider orientation This differs from the less directional void growth in the L-T orientation (Fig 4b), where the pearlite banding is less continuous The specific impact of pearlitic banding or nonmetallic inclusions on fracture behavior in these steels is not treated in this study However, it is expected that both may affect the operating fracture mechanisms during failure One study on banded steel [6] determines that the inclusion content has a greater impact than pearlite banding characteristics on the reduction of upper-shelf Charpy fracture energy J-R Curves J-R curves are shown for fracture toughness tests conducted in both, the T-L and L-T orientations of heat E400 in Figs and 6, respectively It is seen that J3,,m values for tests conducted in the T-L orientation showed a mean of approximately 328 kJ/m in comparison to a mean J3mm value of approximately 580 kJ/m for tests conducted in the L-T orientation This indicates a steeper J-R curve for the L-T orientation as expected The pronounced orientation effect is seen in the composite graph shown in Fig Specifically, the J-R curves from specimens of the L-T orientation exhibit a higher resistance to fracture than those of the T-L orientation This may be caused by the presence of continuous delaminations, which reduce the resistance to fracture, during crack growth in the T-L orientation (see Fig 4a) J-R testing conducted on samples in the low toughness T-L orientation showed remarkable reproducibility, while tests conducted in the high toughness L-T orientation, however, exhibited greater scatter The E400L6 specimen was not side-grooved, and thus showed the expected higher J-R curve due to lower constraint Both E400L4 and E400L8 (see Fig 6) were tested using unloading compliance, which may have contributed to scatter Specimen E400L8 was 20% side grooved, and thus exhibited less crack tunneling than the specimens with 10% side grooves Additional scatter may have resulted from microstructural discontinuities not encountered in the T-L orientation (i.e., banding or inclusion distribution) Test temperature variation and thickness variation had a minimal effect on the J-R curves within their respective tested ranges This is not surprising considering the narrow ranges of both thickness and temperature that were included Figure shows the wide variability of J-R curves from different heats This figure includes preliminary data from heats 1A434 and 382835 in the T-L orientation One possible reason for this E 400 T-L 700 6OO 50O E 400 O T I : 12.7 mm, 294 K ~ 1:3T2:12.7 mm, 300 K AT3:15.2 mm, 298 K o o o 3OO XT4:15.2 mm, 297 K OT5:15.2 mm, 300 K "~ 200 100 0 Da (ram) FIG J-R curves for heat E400 T-L orientation (test temperature and sample thickness shown) Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized 406 FATIGUE AND FRACTURE MECHANICS: 32ND VOLUME FIG ~ J - R curves for heat E400 L-T orientation (test variances shown in legend) FIG J-R curve variability with orientation for heat E400 (test temperature and sample thickness shown in legend) Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized DUNCAN ET AL ON ANALYSIS OF WASTE TANKS 407 Comparison of Different Heats in the T-L Orientation 1400 1200 ,~ A& _ lOOO It : -'" a~ 600 9 E 400 T4: 0.18%C 383835 T15: 0.15% C A 1A 434 L9: 0.08% C ~ 200 IF i i i t i i = i i i 10 ~ Aa (mm) FIG Preliminary J-R curve data from three different heats in T-L orientation behavior could be the carbon content of the respective heats Heats E400 and 382835 (0.18% and 0.15% C, respectively) exhibit lower resistance to ductile tearing than heat IA434 (0.08% C) From this figure, it might appear that a higher carbon content results in lower J-R curve behavior Similar behavior was observed in C-Mn steels by Boulger and Frazier [5] However, in this comparison, manganese and sulfur contents, grain size, temperature and thickness are not held constant (see Tables and 3) Any number of factors, could combine to produce this behavior Further tests will have to be done to quantify carbon and these other effects on J-R curve behavior and their implications on waste tank integrity Data Analysis J3mm Analysis The J-deformation value at a crack extension of m m was chosen as a point of comparison in order to accredit extensive stable crack growth as a result of plasticity In addition, crack extension of m m ensures validity within plastic zone size restrictions The values of J at m m were determined (extrapolated when necessary) from a power law fit to data within the ASTM E 1820 exclusion lines and their intersection with the J-R curve The results of the comparison are listed in Table and Table for tests conducted in the T-L and L-T orientations, respectively Each data set was fit to a normal distribution; the mean, standard deviation, and coefficient of variation of which are included in Table TABLE J3mmdata for heat E400, T-L orientation Sample Technique J3mm (kJ/m2) E400T1 E400T2 E400T3 FA00T4 E400T5 DCPD DCPD DCPD UC DCPD 335 334 326 329 317 Mean Std Dev 328.2 COV 2.2% One-Sided One Sided %p/Tolerance Minimum 90/90 95/90 90/95 95/95 308 304 303 298 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized 408 FATIGUE AND FRACTURE MECHANICS: 32ND VOLUME TABLE 4~J3m,n data for heat E400, L-T orientation One-Sided Sample E400L1 E400L2 E400L4 E400L6 E400L8 E400L9 E400L 10 Technique J3mm Mean DCPD DCPD UC DCPD UC DCPD DCPD 625 583 612 801 532 617 513 580 Std Dev %p/ Tolerance 47 90/90 90/95 95/90 95/95 COV 8% One Sided Minimum 462 434 438 405 and Table 4, as well The results for several one-sided tolerance intervals are provided in these tables With 90% confidence, 90% of the population of toughness results for E400 in the T-L orientation has a J value of greater than 308 kJ/m With 90% confidence, 90% of the population of toughness results for E400 in the L-T orientation has a J value of greater than 462 kJ/m Although the sample sizes are small, recognizing that a larger sample size would provide a reduced tolerance interval, the difference in the standard deviation between the two distributions is significant Comparing the coefficient of variation (COV) for each distribution illustrates this point The COV is the standard deviation normalized by the mean Comparison of the COV for each distribution disclosed that the L-T orientation COV was almost times that of the T-L orientation The difference results directly from the greater scatter in the J-R curves as previously discussed J1c Analysis Jtc values were derived in accord with ASTM E 1820 using a slope of and yield strengths from the materials certificates for the blunting line construction The J~c results are listed in Table Samples E400L4 and E400T4 showed a much higher J~c than their DCPD counterparts in each respective orientation, possibly due to load relaxation during the unloading cycles during the test However, the unloading compliance procedure used on sample E400L8 included repeated unloading cycles at each interval to diminish the effects of load relaxation In addition, E400L8 was 20% sidegrooved to prevent the extensive crack tunneling seen in other samples It was noted that the L-T orientation exhibited a higher Jlc TABLE J1c results for heat E400 (L = L-T orientation, T = T-L ortentation) Sample J (kJ/m2) E400L E400L2 E400L4 E400L6 E400L8 E400L9 E400LI0 E400T1 E400T2 E400T3 EA00T4 E400T5 172 141 387 266 220 141 126 99 74 42 171 87 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized DUNCAN ET AL ON ANALYSIS OF WASTE TANKS 409 Summary J-Integral testing was performed on A285 semi-killed, hot roiled plates to determine the effect of composition, microstructure, and orientation on the fracture behavior of carbon steel for storage tanks at the Savannah River Site The preliminary findings from comparing the initial toughness test results are as follows: Strong dependency on orientation (Lower toughness in T-L than in L-T orientation) Large variability between heats (possibly due to carbon content as well as other variables) Greater scatter for the L-T orientation than for T-L orientation The above conclusions were drawn based primarily on comparison of J-R curves from three heats (E400, 1A434, and 382835) Toughness behavior as a function of each variable will be examined further to ensure the accuracy of the preliminary findings Additional fracture toughness and tensile tests will be performed to determine Jlc values When data acquisition from the entire test matrix is complete, the data will be the basis for a predictive model for flaw behavior in SRS storage tanks Acknowledgments Our colleagues, Drs Bruce J Wiersma, Poh-Sang Lam, and Steven P Harris Jr are gratefully acknowledged for their contribution to this study Dr Wiersma is the lead investigator for service effects to the storage tanks and has provided much of the background work for this study Dr Lam reviewed this manuscript Dr H a m s generated the statistically designed test matrix referred to in this study This work was funded by the U S Department of Energy under contract No DE-AC0996SR18500 References [1] Sindelar, R L., Lam, P S., Caskey, Jr., G R., and Woo, L Y., "Flaw Stability in Mild Steel Tanks in the Upper Shelf Ductile Range-Part I: Mechanical Properties," ASME Journal Pressure Vessel Technology, Vol 122, May 2000, In press [2] Lam, P-S and Sindelar, R L., "Flaw Stability in Mild Steel Tanks in the Upper Shelf Ductile Range-Part II: J-Integral Based Fracture Analysis" ASME Journal of Pressure Vessel TechnoL, Vol 122, May 2000, In press [3] ASTM Standard Test Method for Measurement of Fracture Toughness (E 1820-99), Annual Book of ASTM Standards, Vol 3.01, 1999 [4] Bums, K W and Pickering, F B., "Deformation and Fracture of Ferrite-Pearlite Structures," Journal Iron and Steel Institute, Nov 1964, pp 899-906 [5] Boulger, F W and Frazier, R H., "The Influence of Carbon and Manganese on the Properties of Semikilled Hot Rolled Steel," Journal Metals, Transaction of AIME, May 1954, pp 645-652 [6] ASTM Test Methods for Determining Average Grain Size Using Semiautomanc and Automanc Image Analysis," (E 1382-97), Annual Book of ASTM Standards, Vol 3.01, 1999 [7] Grange, R A., "Effects of Microstructural Banding in Steel," Metallurgical Transactton, Vol 2, Feb 1971, pp 417-426 [8] Shanmugam, P and Pathak, S D., "Some Studies on the Impact Behavior of Banded Mlcroalloyed Steel," Engineering Fracture Mechanics, Vol 53, No 6, 1996, pp 991-1005 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized STP1406-EB/Jan 2002 Author Index A Albrecht, Pedro, 139 B Bar-On, I.,315 C Cassanelh, A N., 49 Chao, Y J., 399 Chapuliot, St6phane, 229 Chien, Ken-Feng, 105 Chlen, K F., 214 Chu, H C., 214 Chung, Y K., 179 K Kashtalyan, Maria, 301 Katou, Takanori, 195 Kim, K S., 179 Kirk, Mark T., Kuo, Roang-Ching, 105,214 Kusukawa, Teppei, 122 L Landes, John D., 263 Lang, Markus, 75 Lee, N W., 179 Li, Ren-Zhi, 105 Liaw, Peter K., 105,214 Lloyd, W R., 353 M D Daniewicz, S R., 381 deVedia, L A., 49 Donoso, Juan R., 263 Duncan, A J., 399 G Gettings, Robert, 336 Graham, Stephen M., 139 Marci, Gtlnter, 75 Marie, St6phane, 229 McDonald, V., Jr., 381 Mear, M E., 353 Miller, K., 399 Minami, Fumiyoshi, 195,247 Moulin, Didier, 229 N Nakai, Yoshikal, 122 Natishan, MarjorieAnn E., Newman, James C., Jr., 279, 353 Nikib, K., 88 H Hayashi, Naohiko, 122 Hsu, H H., 214 Huang, Jenn-Gwo, 105 Huang, Jiunn-Yuan, 105 James, Mark A., 279 Jenkins, M J., 315 Jing, Hongyang, 195 Johnston, William M., Jr., 279 Joyce, James A., 139 O Onozuka, Masakazu, 247 Ortiz, H., 49 Park, J J., 179 Q Quinn, George D., 336, 315 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 411 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized 412 FATIGUE AND FRACTURE MECHANICS: 32ND VOLUME R Radon, J C., 88 Reuter, W G., 353 Reynolds, A P., 399 Sakano, Kenji, 247 Salem, Jonahan A., 315, 336 Sindelar, R L., 399 Skinner, J D., 353 Souus, Costas, 301 Subramanian, K H., 399 Swab, Jeffrey J., 336 T Tijiang, Hemando C., 139 V Van Der Sluys, W A., 37 W Wagenhofer, Matthew, Wainstein, J E., 49 Wallin, Kim, 17 Wright, William J., 139 Xu, Kang, 336 Yamashita, Youichi, 247 Yang, Bing, 105 Young, B A., 37 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized STP1406-EB/Jan 2002 Subject Index A Aluminum alloy, 17,279, 381 separability property, 49 Aspect ratio, 381 A285 steel, 399 ASTM C 1421-99, 315,336 ASTM E 399, 263,353 ASTM E 1820-96, 49, 139, 263 ASTM E 1921-97, Atomic-force microscopy, 122 Crack opening displacement, 75 Crack propagation, 229 Cracks, part-through, 353,381 Crack tip opening angles, three-dimensional analysis, 279 Crack tip opening displacement, 279 critical, 247 Creep crack growth, 179 Cyclic loading, 381 Cyclic plasticity, 75 D Backtracking method, 105, 214 a-Brass, 122 Brittle fracture, 17,247 Brittle-to-ductile transition region, 195 C Calibration function, 263 Ceramics, fracture toughness, 315,336 Chevron notch, 336 Cleavage resistance, 195 Compact type specimens, 88 Compliance ratio method, 139 Composite laminates, modeling multilayer damage, 301 Compressive residual stress, 247 Computational cell model, 195 Constraint loss, 195 Crack arrest toughness, correlation with static initiation toughness, 17 Crack closure, 75, 381 Crack extension, 139 Crack growth, 75, 195,381 creep, 179 ductile, 229 random load, 88 slow, 315 surface, 381 time-dependent, 179 Crack growth rates, 88 Crack initiation, 122 load and location prediction, 353 Crack length, 263 compliance ratio method, 139 estimation, 49 Damage mechanics, 195 Deformation property, 49 Delaminations, matrix crack-induced, 301 Dislocation mechanics, Dissipation rate, 229 Ductile crack growth, 229 Ductile tearing, 399 Dynamic fracture toughness tests, 139 Dynamic testing, 139 E Elastic compliance, 139, 263 Elastic-plastic fracture, 279 Energetic approach, 229 Equivalent constraint model, 301 F Fatigue random, 88 SA533-B1 steels, 105 slip-bands, 122 Fatigue crack propagation, correlation with reduced stress intensity range, 75 Fatigue loading, 301 Fatigue testing, 381 Ferritlc steels, 3, 139 Finite-element analysis, 279 Fractograph, 105 Fracture, 37 Fracture energy, 229 Fracture instability, residual stress effects, 247 Fracture mechanics, 49 Copyright by ASTM Int'l (all rights reserved); Tue Dec 413 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions autho 414 FATIGUE AND FRACTURE MECHANICS: 32ND VOLUME Fracture toughness, 399 ceramics, 315,336 temperature dependency, thin-walled tube, 214 Fracture toughness tests, 17, 139 dynamic, 139 Fuel cladding, 214 P Part-through cracks, 353,381 Plane-strain fracture toughness, 353 Plastic zones, 88 Power-spectrum shapes, 88 Precracked beam, 336 G Q Geometry effect, 195 Quasi-static loading, 301 H R Heat affected zone, 179 High-cycle fatigue, 105 High-strength steel, 353 HY-100, 139 Hydrostatic stress, 75 Random fatigue, 88 J-R-curve, 315 Reference material, 336 Residual stress effects, 247 its-Resistance curves, 279 Round robin, 336 J-integral, 37, 49, 229, 399 K Key curve, 37, 139 L Limit load, 139 Linear-elastic fracture mechanics, 88, 263 Local approach, 195,247 Longitudinal cracking, 301 Low-cycle fatigue, 105 M Martensitic steel, Master Curve applicability, microstructural limits, crack arrest, 17 Matrix crack-induced delaminations, 301 Mlcromechanics, 122 SA533-B1 steels, 105 Scanning atomic-force microscopy, 122 Sensitivity, 37 Separability property, 49 Shear lag method, 2-D, 301 Shp-band, 122 Specimen geometry, 88 Stability, 315 Standard reference material 2100, 336 Static initiation toughness, correlation with crack arrest toughness, 17 Static loading, 301 Stiffness degradation, 301 Strength mismatch, 195 Stress intensity factor, 105 concise, 263 Stress intensity range, reduced, 75 Stress ratios, 381 Structural integrity, 229 Structural tests, 229 Surface crack, in flexure, 336 Surface crack bend specimens, 88 Surface crack growth, 381 N T Normalization, 139 sensitivity study, 37 separability property and, 49 Normalization function, 139 Nuclear reactor pressure vessels, ~lpl factor, 49 Tension-tension fatigue, 301 Thermal cycling, 301 Thin-walled tube, fracture toughness, 214 Transferability analysis, 195 Traverse cracking, 301 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized SUBJECT INDEX U Uncertainty analysis, 381 415 Welds creep crack growth, 179 mismatched, brittle-to-ductile transition region, 195 under-matched, 139 V X VAMAS, 336 X20CrMoV 12 steel, 179 X-specimen test, 214 W Warm preloading, 247 Waste tanks, 399 Weibull stress, 195, 247 Z Zircaloy fuel cladding, 214 Copyright by ASTM Int'l (all rights reserved); Tue Dec 15 13:10:18 EST 2015 Downloaded/printed by University of Washington (University of Washington) pursuant to License Agreement No further reproductions authorized