Application of Microwave Energy to Consolidate Metallic Powder of Titanium


February 14, 2015

Dr. M. Ashraf Imam
Research Professor
Department of Mechanical & Aerospace Engineering
The George Washington University

Thursday, February 12, 2015
2:00pm
800 22nd Street NW, SEH B1270
Washington, DC 20052

Hosted by: Dr. James Lee ([email protected])

Titanium (Ti) has many attractive attributes for military, industrial, and aerospace applications including high specific strength, no magnetic signature, and excellent corrosion resistance. However, its use has been limited by high processing costs. Powder metallurgy is an effective, cost reducing way to produce high-quality, near-net-shape products by sintering (consolidating) at a fraction of the cost of melting and casting. Traditionally, sintering is performed in a conventional vacuum furnace and overall processing times can be many hours to days. Microwave sintering of titanium is a recent development in powder metallurgy of titanium. The sintering is potentially more cost effective and energy efficient compared to conventional sintering methods due to the possibility of direct microwave heating of the titanium powder via in-depth energy deposition augmented by hybrid heating in a ceramic casket. The in-depth heating permits very rapid processing (cycle times of potentially less than 10 minutes) which is intended to preserve a very fine grain structure in the final product resulting in excellent mechanical properties and the possibility of superplastic forming. The process can be also used for composites, laminates, direct alloying, and functionally gradient materials. Evaluations to optimize different parameters for controlling the final density, microstructure, and properties of these materials will be discussed.

Dr. M. Ashraf Imam is a Research Professor since August 2014 in the Department of Mechanical & Aerospace Engineering of The George Washington University. Prior to joining The George Washington University, he was a member of the senior research staff in the Materials Science and Technology Division at the Naval Research Laboratory (NRL). He served as a team leader in pursuing basic research on material structure-property relationship with emphasis on Titanium alloy development and kinetics of transformation in solid phase. During his tenure at NRL, he also held the position of adjunct professor at The George Washington University since late 1980 where he taught materials related subjects in the Department of Mechanical and Aerospace Engineering. He received his Bachelor of Engineering degree in Metallurgy from the Regional Institute of Technology, India; his Master of Science in the field of Metallurgy and Materials Science from Carnegie-Mellon University; and his Doctor of Science in Materials Science from The George Washington University. He has over 230 publications in a variety of refereed journals ranging from Acta Metallurgica to Philosophical Magazine. His expertise on titanium resulted in editing four books on titanium including a large chapter on titanium in Kirk-Othmer Encyclopedia of Chemical Technology. Dr. Imam is a Fellow of the American Society for Metals, International (ASM). He holds membership in the American Society for Metals; and The Minerals, Metals & Materials Society (TMS).