34th Magnetic Materials Center Seminar
December 18, 2006, 10:30
7th floor seminar room, Sengen

B. S. Rao


Investigation of shear band formation in PdNiP and ZrNiAlPd bulk metallic glasses
Y. Chen
Metallic glasses have many attractive properties including high strength, elastic deformability. But BMG deformation mode has not been clarified yet. Different to crystallization metal plastic flow in metallic glasses is offered by shear band. In this seminar I want to show some TEM image from shear band of ZrlNiPd system. And I also want to introduce TEM sample preparation from bending specimen.

Deposition of 8mol % Yttria Stabilized Zirconia by Combustion Flame Pyrolysis and its Thermal Fatigue Study
HARI.S.Goripati
Yttria Stabilized Zirconia (YSZ) is one of the most technologically as well as scientifically sought after materials because of its wide variety of applications. One of its main applications is its use as Thermal Barrier Coating (TBS) on turbine engine components to improve their life time and/or protect them from the hostile environment that is encountered during the operation of the engine. Since YSZ finds its way into every turbine engine operation, an economical way of deposition of material has become a concern for the industry. In this work, we employed an indigenously designed simple chemical technique called Combustion Flame Pyrolysis (CFP) to deposit YSZ TBCs and its suitability for the very application is presented in a more practical manner. The technique's advantages over the conventional methods (EBPVD, APS) will also be addressed in the talk. Governing process parameters such as, substrate material, precursor concentration, substrate temperature and substrate to nozzle distance were optimized to get a suitable condition for producing good quality coatings. The coatings were characterized to study the microstructure, crystal structure, thickness, response to thermal shock tests and failure modes during thermal cycling. The effect of substrate temperature and substrate material on thermal fatigue life is also studied.