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A D V A N C E D M A T E R I A L S & P R O C E S S E S | O C T O B E R 2 0 2 1 4 4 mechanical properties of a functionally graded size small endodontic file due to the laser processing. Bend test re- sults show that the resilience of the unaffected shaft remain unchanged, while the processed tip section showed a 35% increase in flexibility. The torsional deformation at failure in- creased by 37% and the cyclic fatigue life increased by 44%. CONCLUSION Functional grading of NiTi for differential mechanical properties in a monolithic device has been accomplished through selective laser vaporization. The process has been implemented and scaled to commercial levels for dental de- vices. Future applications of the technology in the medical device space may include suture anchors, orthopedic sta- ples, and scoliosis correction devices. Beyond the medical device industry, commercial applications are being devel- oped in actuation (i.e., automotive) and energy generation. ~SMST For more information: Michael Kuntz, vice president of op- erations, Smarter Alloys, 221 Shearson Crescent, Cambridge, Ontario N1T 1J5, 226.808.1279, michaelkuntz@smarteral- loys.com, www.smarteralloys.com. References 1. G. Airoldi and G. Riva, Pseudoelasticity of NiTi Orthodontic Wires Modified by Current Methodologies: A Critical Compari- son, Le Journal de Physique IV, 5 (C2), C2-397, 1995. 2. J.C. Hey and A.P. Jardine, Shape Memory TiNi Synthesis from Elemental Powders, Materials Science and Engineering: A, 188 (1-2), p 291-300, 1994. 3. B.V. Krishna, S. Bose, and A. Bandyopadhyay, Laser Pro- cessing of Net-shape NiTi Shape Memory Alloy, Metallurgical and Materials Transactions A, 38 (5), p 1096-1103, 2007. 4. D.R. Walker, et al., Hybrid Monolithic SMA Actuators, 2007 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, p 1-6, September 2007. 5. D.R.A. Cluff, Fabrication of a New Model Hybrid Material and Comparative Studies of Its Mechanical Properties (Mas- ter’s thesis, University of Waterloo), 2007. 6. M. Barrabés, et al., Mechanical Properties of Nickel–Titani- um Foams for Reconstructive Orthopaedics, Materials Science and Engineering: C, 28 (1), p 23-27, 2008. 7. Farber, E., et al., A Review of NiTi Shape Memory Alloy as a Smart Material Produced by Additive Manufacturing, Materi- als Today: Proceedings, 30, p 761-767, 2020. 8. M.I. Khan, A. Pequegnat, and Y.N. Zhou, Multiple Memory Shape Memory Alloys, Advanced Engineering Materials, 15 (5), p 386-393, 2013. 9. W.J. Buehler, J.V. Gilfrich, and R.C. Wiley, Effect of Low‐ temperature Phase Changes on the Mechanical Properties of Alloys Near Composition TiNi, Journal of Applied Physics, 34 (5), p 1475-1477, 1963. 10. G.F. Andreasen and R.D. Barrett, An Evaluation of Cobalt- substituted Nitinol Wire in Orthodontics, American Journal of Orthodontics, 63 (5), p 462-470, 1973. 11. G.F. Andreasen and R.E. Morrow, Laboratory and Clinical Analyses of Nitinol Wire, American Journal of Orthodontics, 73 (2), p 142-151, 1978. 12. C.J. Burstone, B. Qin, and J.Y. Morton, Chinese NiTi Wire—A New Orthodontic Alloy, American Journal of Orthodontics, 87 (6), p 445-452, 1985. 13. F. Miura, et al., The Super-elastic Property of the Japanese NiTi Alloy Wire for Use in Orthodontics, American Journal of Orthodontics and Dentofacial Orthopedics, 90 (1), p 1-10, 1986. 14. C.J. Burstone, Variable-modulus Orthodontics, American Journal of Orthodontics, 80 (1), p 1-16, 1981. Fig. 5 — Effect of selective vaporization laser processing on the mechanical properties of a pseudoelastic NiTi endodontic file. 8 FEATURE