Strength Variations during Mechanical Alloying Through the Nanostructurnl Range

摘要

During processes of mechanical alloying the characteristic structural length scales of an alloy, including the phase domain size and the crystallite grain size, decrease gradually to a nanocrystalline or even amorphous final state. This method therefore allows a unique avenue to explore the structure-property relationship over several orders of magnitude in length scale. In this work we have considered an ideal equiatomic Ti-Zr system deformed through multiple cold-rolling passes to refine the structural length scales into the nanometer range. The variation of the hardness of the system with decreasing length scale is discussed in terms of traditional Hall-Petch scaling, chemical mixing and the phase evolution of the system, as well as other possible contributions to the hardness variations during processing.