Topic：Glass Formation By Mechanical Alloying 

Abstract

Mechanical alloying (MA) is a high-energy powder processing technique capable of producing a variety of non-equilibrium effects.  These involve microstructural refinement resulting in the formation of novel microstructures and even formation of nanocrystalline materials and constitutional effects leading to formation of a variety of metastable phases including metallic glasses.  Metallic glasses can be synthesized by different methods but those produced by MA appear to possess unique features.  For example, the composition ranges in which metallic glasses can be formed by MA are different from those formed by other methods.  Metals normally immiscible under equilibrium conditions can be made to form alloys and even metallic glasses by MA.  A glassy phase formed by MA can be made to crystallize on continued milling.

Even though a number of criteria have been developed to predict glass-forming ability of alloys by rapid solidification processing methods, they do not seem to be applicable for materials processed by MA.  The present talk will focus on the different aspects of formation of metallic glassy phases achieved by MA with special reference to Fe-based alloy systems. Three specific aspects will be covered: (1) Development of criteria for glass formation, (2) Mechanical crystallization of the glassy phases, and (3) Effect of the nature and amount of different solute elements. The talk will conclude with an outlook for the future of glass formation by  MA methods.

 

 Curriculum Vitae -- C. Suryanarayana