Microstructure, mechanical and anti-corrosion property evaluation of iron-based thin film metallic glasses

Thin film metallic glasses (TFMGs) represent a class of promising engineering materials for structural applications. Despite the effort that has been made in the development of TFMG materials, the iron-based thin film metallic glasses fabricated by sputtering have gained limited attention. In this work, five iron-based Fe-Zr-Ti thin film metallic glasses with different Fe contents ranging from 37.6 to 49.8at.% were prepared by magnetron co-sputtering system using pure Fe, Zr and Ti targets. Through XRD and TEM analyses, the amorphous phase was confirmed for each coating. The glass transition temperature (T_g) and crystallization temperature (T_x) of TFMG increased with increasing Fe content and reached 963K and 989K, respectively, when Fe content was 49.8at.%. The supercooled liquid region was around 26.3 to 51.6°C, which was shown to be unrelated to Fe concentration. The hardness, elastic modulus, and H/E ratio of TFMGs increased with increasing Fe concentration. Based on the HRC-DB test, adequate adhesion quality was obtained for all TFMGs. The corrosion resistance of TFMGs also increased with increasing Fe content and spontaneous passivation behavior was discovered due to the large content of Zr and Ti valve metals. Nevertheless, the corrosion resistance of Fe-Zr-Ti TFMGs was strongly influenced by surface defects. A series of high hardness Fe-Zr-Ti thin film metallic glasses with good adhesion property and adequate corrosion resistance was reported in this study.