Electrodeposited Rare Earth-iron Group Magnetic Films And Their Magnetism

Rare earth(RE)-Iron group(TM) metal alloy films have excellent magnetic, optical and electric characteristics because of the Rare earth' special electron shell structure. They have now been used in electron, information technology, energy, economy,and high technology fields. Currently, there are mainly two methods to prepare Rare earth- Iron group metal alloy: physics and chemistry methods. Moreover, electrodeposition is an alternative method for preparing these alloy films.This method has many advantages such as simple and cost-effectivenes, utilizing easily maintained equipment. The most important is that deposition can change the solution composition and deposition conditions. In this thesis, consequently, binary and ternary Rare earth (RE=Dy,Nd,Eu)-Iron group metal(TM=Co) alloy films have been prepared in low temperature urea-acetamide-NaBr-KBr-RECl3-TMCl2 baths by potentiostatic electrolysis. The electrochemical behavior and co-deposition mechanism were investigated. The phase structure and magnetic properties were studied in detail. The main contents are arranged as follows:1. The development and application of RE-TM alloy films, the preparation method of eiectrodepositied RE-TM alloy films, the essential conception, sort of magnetic theory and the equipments for electrodeposition and measuement were introduced in brief, respectively.2. Cyclic voltammetry was used to investigate the electrochemical behavior of RE3+ and TM2+ in baths on a Pt electrode. The transfer coefficient a and the diffusion coefficient Do for TM2+ were measured, respectively. The co-deposition mechanism was explained well with the electronegativity theory.3. The crystalline phases and the morphology of alloy films on electrodepositon conditions were studied. The change trend of magnetic properties for amorphous binary and ternary RE-TM alloy films in urea molten salt was concluded.