_STP_605-1976.pdf

PROPERTIES RELATED TO FRACTURE TOUGHNESS A symposium presented at the Seventy-eighth Annual Meeting AMERICAN SOCIETY FOR TESTING AND/MATERIALS Montreal,Canada,22-27 June 1975 ASTM SPECIAL TECHNICAL PUBLICATION 605 W.R.Warke,Volker Weiss,and George Hahn,symposium cochairmen List price$15.00 04-605000-30 9 AMERICAN SOCIETY FOR TESTING AND MATERIALS 1916 Race Street,Philadelphia,Pa.19103 Copyright by ASTM Intl(all rights reserved);Sun Dec 27 13:08:01 EST 2015Downloaded/printed byUniversity of Washington(University of Washington)pursuant to License Agreement.No further reproductions authorized.By AMERICAN SOCIETY FOR TESTING AND MATERIALS 1976 Library of Congress Catalog Card Number:76-9741 NOTE The Society is not responsible,as a body,for the statements and opinions advanced in this publication.Printed in Baltimore.Md.August 1976 Copyright by ASTM Intl(all rights reserved);Sun Dec 27 13:08:01 EST 2015Downloaded/printed byUniversity of Washington(University of Washington)pursuant to License Agreement.No further reproductions authorized.Foreword The symposium on Properties Related to Fracture Toughness was presented at the Seventy-eighth Annual Meeting of the American Society for Testing and Materials held in Montreal,Canada,22-27 June 1975.Committee E-24 on Fracture Testing of Metals sponsored the symposium.W.R.Warke,Illinois Institute of Technology,Volker Weiss,Syracuse University,and George Hahn,Battelle Memorial Institute,presided as symposium cochairmen.Copyright by ASTM Intl(all rights reserved);Sun Dec 27 13:08:01 EST 2015Downloaded/printed byUniversity of Washington(University of Washington)pursuant to License Agreement.No further reproductions authorized.Related ASTM Publications Fracture Analysis,STP 560(1974),$22.75,04-560000-30 Fracture Toughness and Slow-Stable Cracking,STP 559(1974),$25.25,04-559000-30 Progress in Flaw Growth and Fracture Toughness Testing,STP 536(1973),$33.25,04-536000-30 Copyright by ASTM Intl(all rights reserved);Sun Dec 27 13:08:01 EST 2015Downloaded/printed byUniversity of Washington(University of Washington)pursuant to License Agreement.No further reproductions authorized.A Note of Appreciation to Reviewers This publication is made possible by the authors and,also,the unheralded efforts of the reviewers.This body of technical experts whose dedication,sacrifice of time and effort,and collective wisdom in reviewing the papers must be acknowledged.The quality level of ASTM publications is a direct function of their respected opinions.On behalf of ASTM we acknowledge with appreciation their contribution.ASTM Committee on Publications Copyright by ASTM Intl(all rights reserved);Sun Dec 27 13:08:01 EST 2015Downloaded/printed byUniversity of Washington(University of Washington)pursuant to License Agreement.No further reproductions authorized.Editorial Staff Jane B.Wheeler,Managing Editor Helen M.Hoersch,Associate Editor Charlotte E.DeFranco,Senior Assistant Editor Ellen J.McGlinchey,Assistant Editor Copyright by ASTM Intl(all rights reserved);Sun Dec 27 13:08:01 EST 2015Downloaded/printed byUniversity of Washington(University of Washington)pursuant to License Agreement.No further reproductions authorized.Contents Introduction I Fracture Toughness ConceptG.c.SIH 3 Fracture Process in Metals 5 Strain Energy Density Theory 7 Bifurcation Near Free Surface 9 Growth Characteristics of Thumbnail Cracks 12 Concluding Remarks 13 Microstructural Aspects of Fracture Toughnessv.WEISS,Y.KASAI,AND K.S I E R A D Z K I 16 Fracture-Toughness DuctiUty Relationships 17 Microstructural Consideration 26 Relationship Between Tensile Properties and Microscopically Ductile Plane-Strain Fracture ToughnessR.H.SAILORS 34 Materials 36 Flow Stress from Crack Opening Displacement 36 Crack Tip Strain Distribution 42 Delineation of Length of Parameter 50 Comparison of Calculated and Measured Values of Ki 52 Medium-Carbon Machinery Steels 55 Discussion 56 Summary and Conclusions 59 Relationship Between the Fracture Toughness and the Crack Tip Radius R.TAGGART,K.K.WAHl,AND R.BEEUWKES,JR.62 Experimental Procedure 64 Results and Discussion 66 Conclusions 69 Microstructure and Toughness of High-Strength Aluminum AlloysJ.T.STALEY 71 Constituent Particles 72 Dispersoid Particles 74 Hardening Precipitates 80 Summary 91 High-Toughness Alloys 94 Discussion 96 Copyright by ASTM Intl(all rights reserved);Sun Dec 27 13:08:01 EST 2015Downloaded/printed byUniversity of Washington(University of Washington)pursuant to License Agreement.No further reproductions authorized.VIII CONTENTS Fracture Analysis of Various Cracked Configurations in Sheet and Plate MaterialsJ.c.NEWMAN,JR.104 Two-Parameter Fracture Criterion 106 Failure Predictions 108 Analysis of Test Data 109 Plane-Stress and Plane-Strain Fracture 118 Concluding Remarks 120 Mechanical Behavior Model for GraphitesJ.D.BUCH 124 Pore-Free,Well-Bonded Isotropic Graphites 125 Porosity 131 Grain Boundaries 136 Anisotropy 138 Volume Effect 140 Discussion 140 Summary 142 Copyright b