Global Summit on
Polymer Science and Composite Materials(GSPSCM2024)
Panorama Hotel Prague, Milevská 1695/7, 140 63 Praha 4-Nusle, Czechia | September 16-18, 2024
Herzl Chai, PhD May. 15, 2018 School of Mechanical Engineering, Faculty of Engineering, Tel-Aviv University, Israel Date of birth: December 24, 1949 EDUCATION Period of Study Field Degree Date of Award 9/1970-7/1974 Tel-Aviv University Mechanical Engineering B.Sc. 6/1975 9/1974-8/1975 Tel-Aviv University Mechanical Engineering M.Sc. 6/1976 9/1976-4/1982 Caltech, Pasadena, CA. Aeronautical Engineering Ph.D. 6/1982 ACADEMIC AND PROFESSIONAL EXPERIENCE 1976 –1981: Research Assistant, California Institute of Technology. 1981 –1982: Research Assistant, Jet propulsion Laboratory, Pasadena, CA. 1982: Post Doctoral Research Fellow, California Institute of Technology. 1982 – 1987: Visiting Scientist, Materials Laboratory, Mechanics and Surface Interaction Branch, Wright-Patterson AFB, Dayton, OH, USA. 1988 – 1989: Research Fellow, Department of Material Science and Engineering, Johns Hopkins University, Baltimore, Maryland. 1989 – 1992: Staff Research Scientist (tenured, Federal employee), Polymers Division, National Institute of Standards and Technology, Gaithersburg, Maryland. 1992 – Present: Faculty member, School of Mechanical Engineering, Tel-Aviv University, Tel-Aviv, Israel, July - Oct., 1992- 2005, 2009 - 2015: Guest Scientist, Material Science and Engineering Laboratory (MSEL), US National Institute of Standards and Technology (NIST). Aug. 2005 – Aug. 2006: Guest Scientist (on leave from TAU), MSEL, NIST. Sept. 2006 – Sept. 2008: Research associate (on leave from TAU), Graduate Aeronautical Laboratories, Caltech, Pasadena, CA. CURRENT RESEARCH ACTIVITIES Mixed mode fracture of adhesive bonds and laminated composites. Contact buckling of plate elements. Indentation fracture of ceramics Crashworthiness of structural elements. Biomechanics. Dental fracture CITATIONS IN THE “SCIENCE CITATION INDEX” According to the Science Citation Index, Dr. Chai has nearly 3000 citations and an H factor of 30. RECENT RESEARCH GRANTS 1. Israeli Science Foundation 2009- 2014. $148,000, awarded soley to Prof. Chai. Research title: An integrated study of the mechanics of fracture and damage in human teeth and dental crowns from contact loading. 2. New York University 2012-2017, $60,000. Fracture behavior of graded materials for dental crowns. 3. US American Dental Association ADAF, NIST 2017-2019, $16,000. Mechanical characterization of dental restorative composites. SCIENTIFIC CONTRIBUTIONS a). Editorial Board member, International Journal of Solids and Structures. b). Chairman, ASTM Round Robin tests on Mode I delamination of composite materials, 1987-1991. c). Reviewer for Int. J. Fracture, Int. J. Solids Structures, J. Mech. Phys. Solids, Eng. Fract. Mechanics, J. Appl. Mechanics, J. Comp. Struct., Int. J. Adhesion and Adhesives, Thin Solid Films, Journal of Materials Research, J. Am. Cer. Soc, Exp. Mech., Surface Coating, J. of Adhesion, Ceramics International, Royal Soc. London - Interface. SOME INVITED LECTURES IN SCIENTIFIC MEETINGS Bond thickness effects in adhesive joints, Gordon Research Conference on Adhesion Science, New Hampton, Aug. 1986. Fracture characteristics of adhesive bonds, Gordon Research Conference on Adhesion Science, Tilton Head, NH, Aug. 1991. Hydraulically pumped cone fracture in brittle solids, Composites at Lake Louise, Lake Louise, Canada, Nov. 2005. PUBLISHED REFEREED ARTICLES 1. H. Chai, C.D. Babcock, W.G. Knauss. One dimensional modeling of failure in laminated plates by delamination buckling. Int. J. Solids and Structures 17, 1069 -1083, 1981. 2. V.H. Kenner, W.G. Knauss, H. Chai. A simple creep torsiometer and its use in the thermorheological characterization of structural adhesives. Experimental Mechanics 22, 75-80, 1982. 3. H. Chai, W.G. Knauss, C.D. Babcock. Observation of impact damage growth in compressively loaded laminates. Experimental Mechanics 23, 329 -337, 1983. 4. H. Chai. The characterization of mode I delamination failure in nonwoven, multidirectional laminates. Composites 15, 277-290, 1984. 5. H. Chai, C.D. Babcock. Two-dimensional modeling of compressive failure in delaminated laminates. J. of Composite Materials 19, 67-98, 1985. 6. H. Chai. On the correlation between the mode I failure of adhesive joints and laminated composites. Engineering Fracture Mechanics 24, 413-431, 1986. 7. H. Chai. Bond thickness effect in adhesive joints and its significance for mode I interlaminar fracture of laminated composites. ASTM STP 893, 209-231, 1986. 8. H. Chai. A note on crack trajectory in an elastic strip bounded by rigid substrates. International Journal of Fracture 32, 211-213, 1987. 9. H. Chai. Shear Fracture. International Journal of Fracture 37, 137-159, 1988. 10. H. Chai. Fracture work thin bondline adhesive joints. Journal of Materials Science Letters 7, 399-401, 1988. 11. H. Chai, S. Mall. Design aspects of the end notch adhesive joint specimen. International Journal of Fracture 36, R3-R8, 1988. 12. H. Chai. Interlaminar shear fracture of laminated composites. International Journal of Fracture 43, 117-131, 1990. 13. H. Chai. Three-dimensional fracture analysis of thin-film debonding. International Journal of Fracture 46, 237-256, 1990. 14. H. Chai. Buckling and postbuckling behavior of elliptical plates, Part I – analysis. Journal of Applied Mechanics 57, 981-988, 1990. 15. H. Chai. Buckling and postbuckling behavior of elliptical plates, Part II – results. Journal of Applied Mechanics 57, 989-994, 1990. 16. H. Chai. Micromechanics of shear deformations in cracked bonded joints. International Journal of Fracture 58, 223-239, 1992. 17. H. Chai. Experimental evaluation of mixed-mode fracture in adhesive bonds. Experimental Mechanics, Dec., 296-303, 1992. 18. H. Chai. Observation of deformation and damage at the tip of cracks in adhesive bonds loaded in shear and assessment of a criterion for fracture. International Journal of Fracture 60, 311-326, 1993. 19. H. Chai. Deformation and failure of adhesive bonds under shear loading. Journal of Materials Science 28, 4944-4956, 1993. 20. M.Y.M. Chiang, H. Chai. Plastic deformation analysis of cracked adhesive bonds loaded in shear. International Journal of Solids and Structures 31, 2477-2490, 1994. 21. H. Chai. Deformation and fracture of particulate epoxy in adhesive bonds. Acta Metallurgica 43, 163-172, 1995. 22. H. Chai, M.Y.M. Chiang. A crack propagation criteria based on local shear strain in adhesive bonds subjected to shear. Journal of the Mechanics and Physics of Solids 44, 1669-1689, 1996. 23. M.Y.M. Chiang and H. Chai. Finite element analysis of interfacial crack propagation based on local shear, part I – deformation. International Journal of Solids and Structures 35, 799-813, 1998. 24. H. Chai, M.Y.M. Chiang. Finite element analysis of interfacial crack propagation based on local shear, part II – fracture. International Journal of Solids and Structures 35, 815-829, 1998. 25. H. Chai. The post-buckling behavior of a bi-laterally constrained column. Journal of the Mechanics and Physics of Solids 46, 1155-1181, 1998. 26. H. Chai, B.R. Lawn, S. Wuttiphan. Fracture in brittle coatings with large interlayer modulus mismatch. Journal of Materials Research 14, 3805-3817, 1999. 27. H. Chai, B.R. Lawn. Role of adhesive interlayer in transverse fracture of brittle layer structures. Journal of Materials Research 15, 1017-1024, 2000. 28. K.S. Lee, Young-Woo Rhee, D. H. Blackburn, N.R. Lawn, H. Chai. Cracking of brittle coating layers adhesively bonded to substrates of unlike modulus. Journal of Materials Research 15, 1653-1656, 2000. 29. B.R. Lawn, K.S. Lee, H. Chai, A. Pajares S. Wuttiphan I.M. Peterson, X. Hu. Damage resistant brittle coating. Advanced Engineering Materials B, 745-748, 2000. 30. H. Chai. Contact buckling and postbuckling of thin rectangular plates. Journal of the Mechanics and Physics of Solids 49, 209-230, 2001. 31. H. Chai. On the post-buckling behavior of bilaterally constrained plates. International Journal of Solids and Structures 39, 2911-2926, 2002. 32. H. Chai, B.R. Lawn. Cracking in brittle laminates from concentrated loads. Acta Materialia 50, 2613-2625, 2002. 33. B.R., Lawn, Y. Deng, P. Miranda, A., Pajares, H. Chai, D.K, Kim. Overview: damage in brittle layer structures from concentrated loads. Journal of Materials Research 17, 3019-3036, 2002. 34. H. Chai. Fracture analysis of thin coatings under plane-strain indentation. International Journal of Solids and Structures 40, 591- 610, 2003. 35. H. Chai. Fracture mechanics analysis of thin coatings under spherical indentation. International Journal of Fracture 119, 263-285, 2003. 36. H. Chai. Interfacial mixed mode fracture of adhesive bonds undergoing large deformation. International Journal of Solids and Structures 40, 6023-6042, 2003. 37. H Chai, B.R. Lawn. Fracture mode transitions in brittle coatings on compliant substrates as a function of thickness. Journal of Materials Research, 19, 1752-1761, 2004. 38. H. Chai. The effect of bond thickness, rate and temperature on the deformation and fracture of structural adhesives under shear loading. International Journal of Fracture 130, 497-515, 2004. 39. H. Chai. Transverse fracture in thin-film coatings under spherical Indentation. Acta Materialia 53, 487-498, 2005. 40. H. Chai, B.R. Lawn. Hydraulically pumped cone fracture in brittle solids. Acta Materialia 53, 4237-4244, 2005. 41. H. Chai. Crack propagation in glass coatings under expanding spherical contact. Journal of the Mechanics and Physics of Solids 54, 447- 466, 2006. 42. H. Chai. On the crush worthiness of a laterally confined bar under axial compression. Journal of Applied Mechanics 73, 834-841, 2006. 43. H. Chai, B.R. Lawn. Failure of brittle layers on polymeric substrates from Vickers indentation. Scripta Materialia 55, 335-338, 2006. 44. H. Chai, B.R. Lawn. Hydraulically pumped cone fracture in bilayers with brittle coatings. Scripta Materialia 55, 343-346, 2006. 45. J-W Kim, S. Bhowmick, H. Chai, B.R. Lawn. Role of substrate material in failure of crown-like layer structures. J. Biomedical Matreials research part B, Applied biomaterials, 81B, 305-311, 2007. 46. H. Chai. Multi-crack analysis of hydraulically pumped cone fracture in brittle solids under cyclic spherical contact. International Journal of Fracture 143, 1-14, 2007. 47. H. Chai, B.R. Lawn. A universal relation for edge chipping from sharp contacts in brittle materials and its use as a simple means of toughness evaluation. Acta Materialia 55, 2555-2561, 2007. 48. J. Jin-Wu Lee, I.K. Lloyed, H. Chai, Y-G. Jung, B.R. Lawn. Arrest, deflection, penetration and reinitiation of cracks in brittle layers across adhesive interlayers. Acta Materialia 55, 5859-5866, 2007. 49. H. Chai, B.R. Lawn. Edge chipping of brittle materials: effect of side-wall inclination and loading angle. International Journal of Fracture 145, 159-165, 2007. 50. J. Jin-Wu Lee, H. Chai, I.K. Lloyed, B.R. Lawn. Crack propagation across an adhesive interlayer in flexural loading. Scripta Materialia 57, 1077-1080, 2007. 51. H. Chai, G. Ravichandran. Transverse fracture in multilayers from uniform tension or line-wedge. International Journal of Fracture 145:299-312, 2007. 52. H. Chai, G. Ravichandran. On the mechanics of surface and side-wall chipping from line-wedge indentation. International Journal of Fracture 148:221-231, 2007. 53. 2007. H. Chai. On optimizing crach energy in cellular structures. International Journal of Solids and Structures 45, 528-539, 2008. 54. H. Chai. Lateral confinement as a means for enhancing load bearingand energy absorption in axially compressed tubes. Thin-walled structures 46, 54-64, 2008. 55. H. Chai, G. Ravichandran.On the mechanics of fracture in monoliths and multilayers from low-velocity impact by sharp or blunt-tip projectiles. International Journal of Impact Engineering 2009;36:375–385. 56. Lucas P.W., Constantino P.J, Lee J.J.-W., Hartstone-Rose A Chai H, Lee W.-K, Dominy N. Primate Dental Enamel: What It Says about Diet. Comparative Dental Morphology 13, 2009. 57. J.J.W. Lee, J.Y. Kwon, H. Chai, P.W. Lucas, V.P. Thompson, B.R. Lawn. Fracture modes in human teeth. Journal of Dental Research 2009;88:224-228. 58. H.Chai, J.J.W. Lee, J.Y. Kwon, P.W. Lucas, B.R. Lawn. A simple model for enamel fracture from margin cracks. Acta Biomaterialia 2009;5:1663-1667. 59. Chai H, Lee J.J-W, Constantino PJ, Lucas PW, Lawn BR. Remarkable resilience of teeth. Proceedings of the National Academy of Science 2009;106:7289–7293. 60. Lucas PW, Constantino PJ, Chalk J, Zicowici C, Wright BW, Fragaszy DM, Hill DA, Lee J.J-W, Chai H, Darvell BW, Lee PKD, Yuen TDB. Indentation as a technique to assess the mechanical properties of fallback food. American Journal of Physical Anthropology, 2009;40:643–652. 61. Chai. H. Indentation-induced subsurface tunneling cracks as a means for evaluating fracture toughness of brittle coatings. Int. J. Fract. 2009;158:15–26. 62. Myoung S, Lee J, Constantino P, Lucas P, Chai H, Lawn BR. Morphology and fracture of enamel. Journal of Biomechanics 2009;42:1947–1951. 63. Chai H, Ravichandran G. Tunneling radial cracks in layered structures from contact loading. Engineering Fracture Mechanics 2009;76:2526–2537. 64. Chai H, Lee J.J-W, Lawn BR. Fracture of tooth enamel from incipient microstructural defects. J of the mechanical Behavior of Biomedicals 2010;3:1 16-120. 65. Zhang Y, Chai H, Lawn BR. Graded Structures for All-ceramic Restorations. J. Dental Research 2010;89:417-421. 66. Chai H, Josell D. Fracture behavior of nano-layered coatings under tension. Thin Solid Films 2010;519:331–336. 67. Constantino, PJ, Lee J.J.-W., Chai H, Zipfel B, Ziscovici C, Lawn BR, Lucas PW. Tooth chipping can reveal the diet and bite forces of fossil hominins. Biology Letters 2010;6: 826–829. 68. Lawn BR, Lee J.J-W, Chai H. Teeth: Among Nature 's Most Durable Biocomposites. Annual Review of Materials Research 2010;40:55–75. 69. Chai H, Lee J.J-W, Lawn BR. On the chipping and splitting of teeth. Journal of the Mechanical Behavior of Biomedical Materials 2011;4:315–321. 70. Chai H. Channel cracking in inelastic film/substrate systems. Int. J. Solids & Strctures 2011;48:1092–1100. 71. Chai H. On the mechanics of edge chipping from spherical indentation. Int. J. Fracture 2011;169:85–95. 72. Amir Barani, Amanda J Melville, Mark B Bush, James J-W Lee, Herzl Chai, Brian R Lawn. Mechanics of longitudinal cracks in tooth enamel, Acta Biomaterialia 2011;7: 2285–2292. 73. Zhang Y, Chai H, Lee J.J-W, Lawn BR. Chipping Resistance of Graded Zirconia Ceramics for Dental Crowns. Journal of Dental research 2012;91(3):311-5. 74. Chai H, Tamse A. Fracture mechanics analysis of vertical root fracture from condensation of gutta-percha. Journal of Biomechanics 2012;45:1673–1678. 75. Chai H, Fox Y. On delamination growth from channel cracks in thin-film coatings. Int. J. Solids & Strctures 2012;48:1092–1100. 76. Lawn, B.R, Chai, H, Barani, A, Bush, M.B. Transverse fracture of canine teeth. Journal of Biomechanics 2013; 46:1561-1567. 77. Chai H, Lee JJ-W, Mieleszko AJ, Chu SJ, Zhang Y. On the interfacial fracture of porcelain/zirconia and graded zirconia dental structures. Acta Biomaterialia 2014;10:3756-61. 78. H. Chai. On mechanical properties of tooth enamel under spherical indentation. Acta Biomaterialia 2014;10:4852–60. 79. H. Chai. On edge chipping in cylindrical surfaces. Int. J. Solids & Strctures 2015;54:12–19. 80. H. Chai. On crack growth in molar teeth from contact on the inclined occlusal surface. Journal of the Mechanical Behavior of Biomedical Materials. 2015;44:76–84. 81. Barani M, Chai H, Lawn BR, Bush MB. Mechanics analysis of molar tooth splitting. Acta Biomaterialia 2015;15:237–243. 82. Chai H, Tamse A. The Effect of Isthmus on Vertical Root Fracture in Endodontically Treated Teeth. Journal of Endodontics 2015;41:1515-1519. 83. Chai H, Kaizer M, Chughtai A, Tong H, Tanaka C, Yu Zhang. On the interfacial fracture resistance ofresin-bonded zirconia and glass-infiltrated gradedzirconia. Dental Materials 2015; 31:1304 – 1311. 84. Chai H. Modelling edge chipping in flint knapping, cutting tools and sharp teeth using a trapezoidal prism structur. International Journal of Solids and Structures 2017;104–105. 85. Chai H, Lawn BR. Fracture resistance of molar teeth with mesial-occlusal-distal (MOD) restorations. Dental Materials 2017;33:e283–e289. 86. Chai H, Mieleszko AJ, Chu SJ2, Yu Zhang. Using glass-graded zirconia to increase delamination growth resistance in porcelain/zirconia dental structures. Dental Materials 2018;34:e8–e14. 87. Chai H, Tamse A. On vertical root fracture in buccal roots of bifurcated maxillary premolars from condensation of gutta-percha. In press, Journal of Endodontics. D. BOOK CHAPTER 1. Tamse A, Chai H. Vertical Root Fractures in Dentistry, in Etiology of Vertical Root Fractures 2015, Springer International Publishing. 2. Yu Zhang, Asima Chughtai, Richard Trushkowsky, 2. Yu Zhang, Asima Chughtai, Richard Trushkowsky, Herzl Chai. Interfaces in fixed dental prostheses: challenges and opportunitie. Dental interface, 2016. E. TECHNICAL REPORTS 1. H. Chai, W.G. Knauss and C.D. Babcock. Visualization of impact damage of composite plates by means of the Moiré techniques. NASA CR 159261, April 1980. H. Chai. An Apple computer program for the analysis of composite laminates. AFWAL-TR-83-4041, 1983. 2. H. Chai. Damage detection techniques in composites. Solid Mechanics Publications, California Institute of Technology, SM 82-7, September 1982. 3. H. Chai. Mixed-Mode Fracture Behavior of Delaminated Films. In Proceedings of the American Society of Composites, 4th Technical Conference, Oct. 3-5, pp. 815-825, 1989. 4. D.L. Hunston, H. Chai. Vamas – A Forum for international cooperation on the development of composite standards, 1990. H. Chai, D.L. Hunston, C. Ortiz. A study on improved laminate for passport applications. NIST Internal report, July 1991. 5. H. Chai. Solids Mechanics Student Laboratory Manual. June 1996.