Speaker: Dr. Vilupanur A. Ravi

Affiliation: California State Polytechnic University, Pomona, CA.

Date: Dec.25^th (Tuesday), 2018

Time: 10:00-11:30AM

Contact: Prof. Junpin Lin (linjunpin@ustb.edu.cn)

Location: 353 Main Building, USTB

Abstract: High temperature degradation of metallic materials may occur by different mechanisms, e.g., oxidation in air, accelerated corrosion under fused salt films (“hot corrosion”), etc. Two broad approaches are available to combat these problems: (a) alloy design and (b) protective coatings/sur face modification. The latter can be achieved through several routes. The particular method chosen is usually the result of the interplay of many factors including economics and design requirements. At Cal Poly Pomona we are developing engineered coatings using Halide Activated Pack Cementation (HAPC). HAPC is a versatile and economical approach to apply coatings of desired compositions to a range of substrates, typically nickel and iron based alloys. If the fundamentals are well understood, the coating process can be controlled to obtain the desired final composition and microstructure. The in situ generation of halide vapor species inside the pack with subsequent transport, surface reactions and solid state diffusion are important phenomena that need attention to achieve optimal coating conditions. In this talk, I will review the halide activated pack cementation process; discuss relevant thermodynamics and kinetics, and present the current status of our work. Specific examples, e.g. diffusion coatings on nickel , steels, etc., will be presented.

Speaker’s short biography: Dr. Vilupanur A. Ravi is Professor and Chair, Chemical and Materials Engineering Department, California State Polytechnic University, Pomona, CA. He is also the Director of Research and Partnerships for the College of Engineering, Cal Poly Pomona. Dr. Ravi’s research interests are in the areas of high temperature materials, coatings and corrosion. His work has been recognized through several awards including the Technical Achievement award from NACE International, the Engineer of the Year Award from the Western Area of NACE International and the Provost’s Award for Excellence in Scholarly & Creative Activities from Cal Poly Pomona. He is a Fellow of six different professional organizations and is a registered Professional Engineer (PE) in California, a Chartered Engineer (CEng) in the UK and a European Engineer (EurIng). He is a former Trustee of ASM International and a past President of Alpha Sigma Mu, the international professional honor society for materials science and engineering. He is the immediate Past President of the Pacific Division of the American Association for the Advancement of Science (2017 2018) and has been elected as Regional Director (2019-2022) for the Southwest Region of Sigma Xi, the Scientific Research Honor Society. Dr. Ravi received his MS and PhD degrees in Metallurgical Engineering from the Ohio State University, Columbus, OH, USA.