used today for examination of glasses, but the common tool of choice for metallic materials is the SEM, in part because of the increased depth of field and higher magnification. Although optical light fractography produces important information regarding fracture surface features, the ability to examine detail on the fracture surface is limited by a maximum magnification of 1000 to 1500 diameters, small depth of field, and limited resolution In some ways, ready availability of the SEM also has limited detailed examination by TEM, because of the ability to place large sections in the microscope for examination in conjunction with reasonably high resolution and without the difficulties in preparing and using fracture surface replicas. However the higher resolution of the tem still remains the tool of choice for examination of fine detail on fracture surfaces and to obtain a more complete understanding of fracture processes such as cleavage(Ref 11). Nonetheless, it is still important to remember that the higher resolution capability of the teM does not guarantee better understanding. It is the self-consistent data gathered over a range of magnifications that provides understanding Additional tools and techniques also have become available, including energy dispersive x-ray spectroscopy (EDS or WDS), the Auger microscope, the variable-pressure SEM, the atomic-force microscope and others These tools have made possible answers to several long-standing questions of importance, such as an improved understanding of temper embrittlement in steels. Advancement in the quantitative understanding of fracture also continues. For example, two relatively recent symposia on fracture in 1996 and 1997(Ref 12 and 13 demonstrate the continued close coupling between fracture mechanics, macroscopic and microscopic continuum mechanics, finite element analysis, dislocation theory, and fractography. Better quantitative understanding of fracture progression and of its microscale appearance and mechanism facilitate potential caling to fabricated engineering components Several compilations of fractographic information(albeit dated in some instances) are also available for metals, polymers, ceramics, and composites. Examples include Ref 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 References 14 and 18 contain polymers. References 15, 16, 17, 18, 19, 20, 21, 22, 23, 24(including fractography, Volume 12 of ASM Handbook) contain metals, and Ref 18 contains composites. Although not an atlas of fractographs, another text(Ref 25) contains several fractographs of metals, polymers, ceramics, and composites, as well as discussion of the relationship between microstructure and fractographic appearance References cited in this section 2. R.W. Honeycombe, The Plastic Deformation of Metals, Edward Arnold and ASM, 1984 3. Fracturing in Metals, American Society for Metals, 1948 Fracture, B L. Averbach, D K. Fellbeck, G.T. Hahn, and D A. Thomas, Ed, John Wiley, New York, 1959 5. Fracture of solids, D. C. Drucker and J.J. Gilman, Ed, Gordon and Breach Science Publishers, 1962 6. C D. Beachem, Interpretation of Electron Microscope fractographs, NRL Report 6360, U.S. Naval Research Laboratory, Washington, D. C, 21 Jan 1966 7. Electron Fractography, STP 436, ASTM, 1968 8. G. Henry and J. Plateau, La Microfractographie, Institut de recherches de siderugie Francais, 1967 9. Application of Electron Microfractography to Materials Research, STP 493, ASTM, 1971 10. Fractography, Microscopic Cracking Processes, STP 600, C D Beachem and W.R. Warke, Ed ASTM 1976 11. D. Hull, Fractography, Cambridge University Press, 1999 12. Cleavage fracture. K.S. Chan. Ed.. TMS 1996 Thefileisdownloadedfromwww.bzfxw.comused today for examination of glasses, but the common tool of choice for metallic materials is the SEM, in part because of the increased depth of field and higher magnification. Although optical light fractography produces important information regarding fracture surface features, the ability to examine detail on the fracture surface is limited by a maximum magnification of 1000 to 1500 diameters, small depth of field, and limited resolution. In some ways, ready availability of the SEM also has limited detailed examination by TEM, because of the ability to place large sections in the microscope for examination in conjunction with reasonably high resolution and without the difficulties in preparing and using fracture surface replicas. However the higher resolution of the TEM still remains the tool of choice for examination of fine detail on fracture surfaces and to obtain a more complete understanding of fracture processes such as cleavage (Ref 11). Nonetheless, it is still important to remember that the higher resolution capability of the TEM does not guarantee better understanding. It is the self-consistent data gathered over a range of magnifications that provides understanding. Additional tools and techniques also have become available, including energy dispersive x-ray spectroscopy (EDS or WDS), the Auger microscope, the variable-pressure SEM, the atomic-force microscope and others. These tools have made possible answers to several long-standing questions of importance, such as an improved understanding of temper embrittlement in steels. Advancement in the quantitative understanding of fracture also continues. For example, two relatively recent symposia on fracture in 1996 and 1997 (Ref 12 and 13) demonstrate the continued close coupling between fracture mechanics, macroscopic and microscopic continuum mechanics, finite element analysis, dislocation theory, and fractography. Better quantitative understanding of fracture progression and of its microscale appearance and mechanism facilitate potential scaling to fabricated engineering components. Several compilations of fractographic information (albeit dated in some instances) are also available for metals, polymers, ceramics, and composites. Examples include Ref 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24. References 14 and 18 contain polymers. References 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 (including Fractography, Volume 12 of ASM Handbook) contain metals, and Ref 18 contains composites. Although not an atlas of fractographs, another text (Ref 25) contains several fractographs of metals, polymers, ceramics, and composites, as well as discussion of the relationship between microstructure and fractographic appearance. References cited in this section 2. R.W. Honeycombe, The Plastic Deformation of Metals, Edward Arnold and ASM, 1984 3. Fracturing in Metals, American Society for Metals, 1948 4. Fracture, B.L. Averbach, D.K. Fellbeck, G.T. Hahn, and D.A. Thomas, Ed., John Wiley, New York, 1959 5. Fracture of Solids, D.C. Drucker and J.J. Gilman, Ed., Gordon and Breach Science Publishers, 1962 6. C.D. Beachem, Interpretation of Electron Microscope Fractographs, NRL Report 6360, U.S. Naval Research Laboratory, Washington, D.C., 21 Jan 1966 7. Electron Fractography, STP 436, ASTM, 1968 8. G. Henry and J. Plateau, La Microfractographie, Institut de Recherches de Siderugie Francais, 1967 9. Application of Electron Microfractography to Materials Research, STP 493, ASTM, 1971 10. Fractography, Microscopic Cracking Processes, STP 600, C.D. Beachem and W.R. Warke, Ed. ASTM, 1976 11. D. Hull, Fractography, Cambridge University Press, 1999 12. Cleavage Fracture, K.S. Chan, Ed., TMS, 1996 The file is downloaded from www.bzfxw.com