Wear Behavior of Annealed Atomic Layer Deposited Alumina
Department: Mechanical Engineering and Mechanics
Advisor: Brandon Krick
Atomic layer deposited (ALD) alumina is a promising candidate for applications in protective wear-resistant coatings in micro-/nano-electromechanical systems (MEMS/NEMS). While the tribological properties of ALD alumina may be affected by numerous factors related to processing, environment, and operating conditions, its wear behavior is neither quantified nor well understood. In this study, ALD alumina coatings are annealed at different temperatures, then subjected to sliding wear testing in a humid air environment. Tribological properties appear to be heavily influenced by annealing temperature. Surprisingly, the wear rate decreased by about two orders of magnitude after annealing at 1000°C for 1 hour. This improvement in wear resistance was shown to be influenced by the formation of crystalline phases as annealing temperature increased. Thermally-induced diffusion at the coating/substrate interface and tribofilm formation are likely important mechanisms as well.
About Zakaria Hsain:
Zakaria Hsain is a senior at Lehigh University pursuing a B.S. in mechanical engineering with a minor in aerospace engineering. He has worked for about two years with Dr. Nicholas Strandwitz and Dr. Brandon Krick on numerous projects. The bulk of his research occurs at the intersection of mechanical engineering, materials science and surface physics, and centers on the tribological properties of alumina thin films grown by atomic layer deposition. He has recently published a first-author peer-reviewed journal article. Aside from research, Zakaria is involved with the Office of Student Leadership Development as a Ropes Course facilitator, the Muslim Students Association, and the Multifaith Initiative. Additionally, as part of the Martindale Student Associates Program, he is preparing a journal article on innovation and economic diversification in Peru. After graduation, he plans to pursue doctoral studies.