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While thin film metallic glass (TFMG) materials have been studied widely due to their easy fabrication process and unique properties, the W-based or W-containing TFMGs have yet to be explored extensively. In this work, four W-containing Zr–W–Ti TFMGs were fabricated by a magnetron co-sputtering system. The power of W target was adjusted to obtain TFMGs with different W concentrations. The amorphous phase of TFMG was determined by X-ray diffraction and high resolution transmission electron microscopy. In cross-sectional morphologies, a vein fracture pattern was observed using field-emission scanning electron microscopy. Although the hardness of W-containing Zr–W–Ti TFMG was not very high, the hardness of coating increased with increasing W content to reach 7.6 GPa. Good adhesion quality and adequate corrosion resistance were also obtained for each Zr–W–Ti TFMGs.

Metallic glasses with the disordered atomic structure have unique properties of high strength, high toughness, good corrosion and abrasion resistances. These materials are thus potentially useful for medical application. In this work, we evaluate the antibacterial property and durability of materials sputter-coated with Zr-based (Zr53Cu33Al9Ta5) and Cu-based (Cu48Zr42Ti4Al6) thin film metallic glasses (TFMGs). Good adhesive coating of Zr-based TFMG on the dermatome gives rise to blade sharpness improvement of ~ 27%, substantial surface roughness reduction of ~ 66% and smoother incised wound on the pig skin. As compared to 48.8° on the bare Si wafer, the water contact angles of 119.5° and 106.6° for Zr- and Cu-based TFMGs, respectively, reveal the hydrophobic characteristic of the coated surfaces. The bacterial adhesion of Escherichia coli and Staphylococcus aureus to both Zr- and Cu-based TFMGs is hindered to different extents.

In-situ heating fluctuation electron microscopy and scanning transmission electron microscopy have been utilized to study compositional and structural heterogeneities in Zr51Cu32Al9Ni8 thin films upon annealing. Composition fluctuations are present in the as-deposited thin films. Well below the glass transition temperature, the composition fluctuations increase with annealing time. Short- and medium-range order also change with annealing temperature. The observed heterogeneities in the glass structure persist until annealing causes crystallization. The 20 nm thick Zr51Cu32Al9Ni8 films contain oxide layers both at the surface and the film/substrate interface with the total thickness of 7–8 nm. In-situ annealing increased the oxygen content of the whole films to about 24 wt.% after 2 h at 400 °C.

Recently thin film metallic glass represents a class of promising engineering materials for structural applications. In this work, the Zr-based thin film metallic glass (TFMG) was fabricated on the Si and AISI 420 substrates using a Zr–Cu–Ni–Al alloy and pure Zr metal targets by a pulsed DC magnetron sputtering system. The chemical compositions, crystalline structures, microstructures and corrosion behavior in hydrochloric (HCl) aqueous solutions of Zr-based TFMGs were investigated. The results showed that the surface morphologies of Zr-based TFMG were very smooth. A compact and dense structure without columnar structure was observed. The amorphous structure of Zr-based TFMG was characterized by the X-ray diffractometer and transmission electron microscopy analyses. After the potentiodynamic polarization test, the better corrosion resistance was achieved for the Zr-based TFMG coated AISI 420 in 1 mM HCl aqueous solution. Based on the surface morphologies and chemical analysis results of the corroded surfaces, the pitting, crevice corrosion and filiform corrosion were found. The corrosion mechanisms of the Zr-based TFMG were discussed in this work.

Five nanostructured Cr 2 N/Cu multilayer coatings were deposited by a bipolar asymmetric reactive pulsed DC magnetron sputtering system, and various bilayer periods (Λ) were achieved by controlling the holding time of Si substrates in the plasma of Cr or Cu. The hardness and elastic modulus of multilayer coatings were investigated by means of a nanoindenter. Nano-scratch and nano machining experiments on multilayered coatings were conducted using atomic force microscopy (AFM) in air and DI-water, respectively. According to the groove depth, width , and coefficient of friction (COF) obtained from nano-scratch tests, influences of scratch cycle numbers and bilayer periods on the scratchability of Cr 2 N/Cu multilayered thin films were examined. It was observed that after nano-scratch experiments in air and water, the COF values and the amount of removed material increased with increasing bilayer period. After nano-machining tests in air and water, different types of the cutting chip pile-ups were observed. In this work, the surface tribological properties and machinability of Cr 2 N/Cu multilayered thin films when using an AFM are discussed.

Nine kinds of nanostructured Cr2N/Cu multilayer thin films were deposited by the bipolar asymmetry reactive pulsed DC magnetron sputtering system. The antibacterial tests of coatings with various bilayer periods (Λ) and different Cr2N/Cu thickness ratios were performed to evaluate the bactericidal ability by E. coli, S. aureus and P. aeruginosa, respectively. The Λ value, thickness values of Cr2N to Cu layers significantly affected the bactericidal rates. The 100% bactericidal rates were achieved when the Λ value reached 20 nm. For the same Λ = 12 nm Cr2N/Cu multilayered coatings, the thickness ratio of Cr2N to Cu also showed strong influence on the bactericidal rates.