Extremely hard, damage-tolerant ceramic coatings with functionally graded, periodically varying architecture》.pdfVIP

Available online at Acta Materialia 61 (2013) 193–204 /locate/actamat Extremely hard, damage-tolerant ceramic coatings with functionally graded, periodically varying architecture a,b,⇑ c a d d c e,⇑ P.C. Wo , X.L. Zhao , P.R. Munroe , Z.F. Zhou , K.Y. Li , D. Habibi , Z.H. Xie a Electron Microscope Unit, University of New South Wales, Sydney, NSW 2052, Australia b School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164-2920, USA c School of Engineering, Edith Cowan University, Joondalup, WA 6027, Australia d Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong, People’s Republic of China e School of Mechanical Engineering, University of Adelaide, SA 5005, Australia Received 15 January 2012; received in revised form 30 August 2012; accepted 13 September 2012 Available online 29 October 2012 Abstract Functionally graded, multilayer coatings consisting of alternating TiN/TiSiN layers were synthesized in an attempt to overcome the innate brittleness of TiSiN nanocomposite coatings, whilst maintaining high hardness. These coatings exhibited key structural charac- teristics that are known to render many naturally occurring materials extremely hard and robust. Transmission electron micros