Dr. Hayes is currently the General Manager of Exponent Science and Technology Consulting Co. (Exponent China). Exponent China, located in the city of Hangzhou, near Shanghai, is a wholly owned subsidiary of the parent company, Exponent Inc., headquartered in Menlo Park, California.
Dr. Hayes utilizes his background in mechanical and metallurgical engineering to perform failure analyses and accident reconstruction. He specializes in failure analysis, materials science, metallurgy, creep, and fatigue.
Dr. Hayes has served as a failure analysis consultant on cases involving failures of metals, plastics, and glasses in consumer products such as automobile and bicycle parts, furniture, and personal protective equipment. He has performed accident reconstruction for automobile, train, motorcycle, and bicycle accidents. Dr. Hayes routinely performs root cause analyses of portable consumer products involving battery failures. He has conducted numerous on-site audits of battery manufacturers as part of failure investigations and new product qualifications.
Before joining Exponent, Dr. Hayes served as a Senior Scientist with The Institute of Risk & Safety Analyses in Woodland Hills, California. He has successfully qualified and testified as an expert in trials, depositions, and arbitrations in California and Nevada.
Mikolajczak C, Harmon J, Hayes T, Megerle M, White K, Horn Q, Wu M. Li-ion battery cell failure analysis: The significance of surviving features on copper current collectors in cells that have experienced thermal runaway. Proceedings, 25th International Battery Seminar & Exhibit for Primary & Secondary Batteries, Small Fuel Cells, and Other Technologies, Fort Lauderdale, FL, March 17–20, 2008.
Mikolajczak CJ, Hayes TA, Megerle MV, Wu M. A scientific methodology for investigation of a lithium ion battery failure. 2007 International Conference on Portable Information Devices, Orlando, FL, March 2007.
Hayes TA, Rosen RS and Kassner ME. Creep fracture of zirconium alloys. J Nuc Mater 2006; 353:109–118.
Hayes TA, Kassner ME. Creep of zirconium and zirconium alloys. Metall and Mater Trans 2006; 37A:2389–2396.
Hayes TA, Kassner ME. Creep of zirconium and zirconium alloys. Proceedings, Symposium Sponsored by Materials Science and Technology, Creep Deformation and Fracture, Design, and Life Extension, pp. 13–25, Pittsburgh, PA, September 25–28, 2005.
Hayes TA, Rosen RS, Kassner ME. Creep fracture of zirconium alloys. Proceedings, Symposium Sponsored by Materials Science and Technology, Creep Deformation and Fracture, Design, and Life Extension, pp. 27–39, Pittsburgh, PA, September 25–28, 2005.
Hayes TA. Creep and creep fracture of zirconium and zirconium alloys. Ph.D. Dissertation, University of California, San Diego, 2004, 391 pp.
Kassner ME, Hayes TA. Creep cavitation in metals. Int J Plasticity 2003; 19:1715–1748.
Barrabes S, Daraio C, Kassner ME, Hayes TA, Wang MZ. Dynamic restoration mechanisms and discontinuous dynamic recrystallization in a-Zirconium. pp. 825–839. In: Light Metals, T. Lewis (ed), Canadian Inst. of Mining, Metallurgy and Petrol. Engineers, Montreal, 2002.
Hayes TA, Kassner ME, Rosen RS. Steady state creep of a-Zirconium at temperatures up to 850°C. Metall Mater Trans 2002: 33A:337–343.
Hayes TA, Rosen RS, Kassner ME, Vecchio KS. Analysis of dry storage temperature limits for zircaloy-clad spent nuclear fuel based on diffusion-controlled cavity growth. Proceedings, Scientific Basis for Nuclear Waste Management XXIII, Boston, MA, Materials Research Society, Vol. 608, pp. 23–28, 2000.
Kassner ME, Hayes TA. Subgrain strengthening revisited II. Proceedings, Deformation Processing and Properties of Structural Materials, Honorary Symposium for Professor Oleg D. Sherby (invited paper), TMS, Warrendale, PA, pp. 121–130, 2000.
Hayes TA, Rosen RS. Steady state creep of zirconium at high and intermediate temperatures. Proceedings, 8th Int’l Symposium on Plasticity and its Current Applications, Plastic and Viscoplastic Response of Materials and Metal Forming, Neat Press, 2000, pp. 342–344, Whistler, Canada, July 16–20, 1999.
Rosen RS, Hayes TA. Modeling creep rupture of zirconium alloys. Proceedings, 8th Int’l Symposium on Plasticity and its Current Applications, Plastic and Viscoplastic Response of Materials and Metal Forming, Neat Press, 2000, pp. 369–371, Whistler, Canada, July 16–20, 1999.
Hayes TA, Rosen RS, Kassner ME. Critical analysis of interim dry storage temperature limits for zircaloy-clad spent nuclear fuel based on diffusion-controlled cavity growth. Lawrence Livermore National Laboratory, Report UCRL-ID-131098, 145 pp, December 1999.
Hayes TA, Kassner ME. Elastic constants, hardness and wear, intrinsic stress and thermal expansion coefficients in a-Si and Si:H. pp. 356–372. In: Properties of Amorphous Silicon and Its Alloys, T.M. Searle (ed), Inst. Electrical Engineers INSPE, Stoneridge, Herts, UK, 1998.
Hayes TA, Kassner ME, Rosen RS, Amick DA. Thermal stability of surface deformed zirconium. J Nuc Mater 1997; 246:60–69.
Hayes TA. Thermal stability of surface treated zirconium. Masters Thesis, Oregon State University, 137 pp, 1996.
Bergsm SC, Kassner ME, Li X, Delos-Reyes MA, Hayes TA. The optimized properties of the new aluminum alloy 6069. J Eng Mater Perf 1996; 5:111–116.
Book Chapters
Hayes TA, Kassner ME. Elastic constants, hardness and wear, intrinsic stress and thermal expansion coefficients in a-Si and Si:H. pp. 356–372. In: Properties of Amorphous Silicon and its Alloys. T.M. Searle (ed), Inst. Electrical Engineers INSPE, Stoneridge, Herts, UK.
Presentations
Hayes TA, Du Y. A scientific methodology for investigation of a lithium ion product failure. 4th International Battery Exhibition, Shanghai, China, November 9, 2005.
Hayes TA. Creep of zirconium and zirconium alloys. Creep Deformation and Fracture, Design, and Life Extension, Materials Science & Technology (MS&T’05), Pittsburgh, PA, September 25–28, 2005 (Invited Talk).
Hayes TA. Creep fracture of zirconium alloys. Creep Deformation and Fracture, Design, and Life Extension, Materials Science & Technology (MS&T’05), Pittsburgh, PA, September 25–28, 2005 (Invited Talk).
Hayes TA. Analysis of dry storage temperature limits for Zircaloy-clad spent nuclear fuel based on diffusion-controlled cavity growth. Scientific Basis for Nuclear Waste Management XXIII, Materials Research Society, Boston, MA, 2000.
Hayes TA. Steady state creep of Zirconium at high and intermediate temperatures. Plastic and Viscoelastic Response of Materials and Metal Forming, Whistler, Canada, July 16–20, 1999.
Hayes TA. Modeling creep rupture of Zirconium alloys. Plastic and Viscoelastic Response of Materials and Metal Forming, Whistler, Canada, July 16–20, 1999.