Atomic disorder produced in cobalt aluminide by mechanical milling

Abstract

This chapter focuses on amorphous magnetic rare earth alloys. These metal-metalloid amorphous alloys are produced typically by either rapid quenching from the liquid state, electro-deposition from solution, electro-less deposition, or evaporation onto cooled substrates. In late 1972, a new class of amorphous materials was produced: the rare earth-transition metal amorphous alloys (e.g. Tb0.33 Fe0.66 or simply TbFe2) that contained no metalloid or glass-former atoms. The rare earth amorphous alloys were found to possess a number of unique features, mostly related to their magnetic state, including magnetic bubble domain propagation, a giant coercive field behavior at low temperatures, evidence of angstrom-sized magnetic micro-domains, and a unique dependence of bulk magnetic ordering temperatures (Curie points) on magnitude of the rare earth effective spin. This chapter discusses these and other aspects of the rare earth transition metal amorphous materials.