| In this paper, TbDy-Fe and Sm-Fe GMFs deposited on bronze,pure copper andpolyimide substrates were prepared by IBS and MS. By altering the substrate state,technical parameters and annealing treatment, the change of stress and structure in thethin film were obtained, which resulted in improving the magnetostriction of RGMFs.The surface appearances and structures of RGMFs were measured and investigated byusing XRD, TEM, SEM. The magnetostriction of RGMFs were measured bylibrate-displacement apparatus based on theory of capacitance. An apparatus had beendevised and refitted to measure the radius of amorphous RGMF samples, then the thinfilm stress was calculated. The radom error and system error were analysed and discussedduring measure and calculation, and the relative error of thin film's stress was furtherstudied during the process of experiment. The effect of magnitude of thin film stress andanneal of thin film on the magnetostriction of RGMFs were analysed and discussed. Theexperimental results were shown as follows. 1. The surfaces of TbDy-Fe and Sm-Fe GMFs deposited by sputtering all werecompact and combined well with the substrates. The thickness of thin film showeddisciplinary changes on the angle of sputtering at 42.5o,45oand 47.5o, among which thedeposited velocity improved when the angle of sputtering was augmented. 2. When TbDy-Fe and Sm-Fe GMFs were deposited on bronze substrates by IBS,the stress magnitude of the thin films deposited on bronze substrates which wereintercepted parallel to rolling orientation were separately 400～500MPa and 450～550MPa, while the stress magnitude of the thin films deposited on bronze substrateswhich were intercepted plumb to rolling orientation were separately only 200～300MPaand 150～200MPa, which were all minus value and regarded as compressive stress. Thestress magnitude of the thin films deposited on annealing bronze substrates which wereintercepted parallel to rolling orientation reduced compared to the thin films deposited onbronze substrate without annealing, on the contrary, the stress magnitude of the thin filmsdeposited on annealing bronze substrates intercepted plumb to rolling orientationincreased compared to the thin films deposited on bronze substrate without annealing.The experimental datas ofthe thin film stresses and magnetostriction indicated that the IImagnetostriction properties of TbDy-Fe GMF fall down with its compressive stressincreases ont only in low magnetic field but also in high magnetic field, and themagnetostriction sensibility of Sm-Fe GMF is promoted when its compressive stressincreases. 3.Under the experimental condition,the structure of Sm-Fe GMFs deposited onbronze by MS are amorphous mixed with a small amount of micro-crystal, which exhibitneat and smooth surface. The magnitude of the thin films stress are between 700 MPa and900MPa which are compressive stress and larger than thin films deposited by IBS. Withthe working atmosphere pressure increase, the Sm-Fe GMF compressive stress has atrend to reduce and its magnetostriction properties are evidently promoted, which precedeto the magnetostriction properties of Sm-Fe GMFs deposited on the same conditionalsubstrate by IBS. 4.The as-deposited TbDy-Fe GMF and annealing temperature lower than 400℃exhibit amorphous structure. When it was annealed at 400℃,crystal convertion beginsand the amount of crystals become more, the size of crystals grow up with thetemperature of anneal treatment higher than 400℃. When anneal treatment temperatureat 200 ℃, the magnetostriction properties of TbDy-Fe GMF was improved and itsmagnetostriction sensibility attain 32.20×10-4T-1 at lower than 0.2T, and themagnetostrictive coefficient arrive at 11.04×10-4. With the temperature of annealtreatment higher than 200 ℃, its magnetostriction properties fall down rapidly,whichwas resulted from oxidation and heat fatigue during repeatedly annealingprocess.
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