R. Gansert, AMTS Incorporated, Simi Valley, CA; C. Melnyk, S. Schroeder, D. Grant, California Nanotechnologies, Inc., Cerritos, CA
Nano, near-nano, and multi-modal grained materials show great potential for application in many commercial industries. The Hall-Petch relationship cites the strengthening of materials by reducing the average crystallite size. A study is proposed to investigate the increase in mechanical properties provided by nano, near-nano as well as multi-modal grained powders used in powder metallurgical applications. Consolidations of processed materials will be produced using Spark Plasma Sintering (SPS). Nano-crystalline titanium, and titanium alloy powders and will be processed via cryogenic milling. The mechanical properties of the nano, near-nano and multi-modal crystalline materials will be compared to conventional materials of the same composition. Initial testing of titanium based materials indicates an increase in strength and hardness by 2 to 3 times from the use of nano and near nano crystalline structures. Cryo milled powders and the consolidated forms of these powders will be examined using microstructural analysis and mechanical testing.
