On annealing-induced amorphization and anisotropy in a ferromagnetic Fe-based film: A magnetic and property study

Abstract

Magnetic and property characteristics of sputtered Fe65Ti13Co8Ni7B6Nb1 film in as-deposited and annealed conditions are examined. The film is transformed into various nanoscale and amorphous structures during annealing. Fully amorphous structure is obtained at 773–823K, whereas nanocrystalline γ-fcc FeNi, cubic Fe(Ni) and FeNi phases evolve sequentially at various temperatures. Amorphization and nanocrystallization yield alterations in electrical, hardness and magnetic properties with good soft magnetic properties obtained at 898K. Magnetic force images reveal stripe magnetic domain structures at 923–973K, indicating the presence of the strong stress-induced perpendicular magnetic anisotropy due to the combined effect of the positive magnetostriction and the compressive stress.

Recent progress in metallic glasses in Taiwan

“…The thin film amorphous alloys are generally called as the thin film metallic glasses (TFMGs), which can be prepared by many physical vapor deposition methods such as sputtering or evaporation. TFMGs might have tremendous application potentials in the areas of surface coating and MEMS [68,69]. Co-sputtering by two or three guns appears to be a promising process in studying the TFMGs with a wide variation of composition and microstructure.…”

“…It is also the first to report annealing-induced amorphization in glass-forming Zr 47 Cu 31 Al 13 Ni 9 [68] and Fe 65 Ti 13 Co 8 Ni 7 B 6 Nb 1 [69] films at a temperature within the supercooled liquid region (Fig. 13 [69]).…”

“…Typical TEM bright-field images and diffraction patterns of the Fe 65 Ti 13 Co 8 Ni 7 B 6 Nb 1 films in as-deposited and annealed conditions[69].…”

High thermal stability of the amorphous structure of GexNbTaTiZr (x=0.5, 1) high-entropy alloys

“…Accordingly, T h of Ge 0.5 NbTaTiZr is 700 °C while T h of GeNbTaTiZr is 750 °C. If we compare T h of GeNbTaTiZr (or Ge 0.5 NbTaTiZr) films with the reported T h of thin film metallic glasses (TFMGs) despite the different annealing time, as plotted in Fig 3(c) [12][13][14][15][16], large improvement of 200 °C (or 150 °C) is seen as compared to the best Fe 65 Ti 13 Co 8 Ni 7 B 6 Nb 1 TFMG. It should be noted that the annealing time of amorphous Ge x NbTaTiZr (x = 0.5, 1) is 60 times that of Fe 65 Ti 13 Co 8 Ni 7 B 6 Nb 1 TFMG.…”

Influence of casting temperature on the thermal stability of Zr-based metallic glasses

“…However, metallic glasses are thermodynamically metastable and will undergo devitrification upon heating, which can destroy those novel properties due to embrittling the metallic glasses [4][5][6]. On the other hand, the metallic glass composites prepared through annealing can be reinforced by the formation of nanocrystalline, leading to apparent improvement of the mechanical, magnetic and some other properties of the materials [7][8][9][10]. Obviously, the thermal stability is a key property to understand the structural transformation during either the solidification or annealing process.…”