1 - Introduction

Abstract

This chapter provides an overview of mechanical alloying (MA). MA is a unique process for fabrication of several alloys and advanced materials at room temperature. It is used to produce alloys and compounds that are difficult or impossible to be obtained by conventional melting and casting techniques. The MA process was developed in 1966 at The International Nickel Company (INCO) as part of a program to produce a material combining oxide dispersion strengthening with gamma prime precipitation hardening in a nickel-based super alloy intended for gas turbine applications. This chapter focuses only on the application of milling for fabrication of engineering materials via MA process. The major process in MA for producing quality powders of alloys and compounds with well-controlled microstructure and morphology is the repeated welding, fracture, and rewelding of the reactant mixed powders. Several types of mills are employed for such purpose. The MA process is successfully performed in both high-energy mills, and low-energy tumbling mills. The MA process is affected by several factors that play very important roles in the fabrication of homogeneous materials, such as types of mills, types of milling media, milling timing, and milling temperature.