The structure and properties of chromium diboride coatings deposited by pulsed magnetron sputtering of powder targets

Microstructure of direct current and pulse magnetron sputtered Cr–B coatings

“…However, these properties depend strongly on the deposition process and parameters [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. To understand the relationships between these deposition parameters and the resulting properties requires detailed structural analysis of the films.…”

“…To understand the relationships between these deposition parameters and the resulting properties requires detailed structural analysis of the films. This understanding may give important information about the characteristics of the deposition processwhich in this particular case is a recently developed method involving magnetron sputtering of loosely packed powder (LPP) targets [1][2][3][4] -and then point to directions for improvement. The combination of a pulsed magnetron sputtering (PMS) process [5] with the use of blended powder targets is a new, highly flexible deposition tool, suitable for the development of novel physical vapour deposition (PVD) coating systems and the optimisation of film properties.…”

Preparation of borides in Nb–B and Cr–B systems by combustion synthesis involving borothermic reduction of Nb2O5 and Cr2O3

“…Among them, NbB 2 is promising for high-temperature structural applications [5] and has been recognized as a superconductor [6,7]. CrB 2 shows potential not only as a high-temperature structural material [3], but also as a hard coating or a protective layer on tools and materials exposed to wear and corrosion [8,9].…”

Ion fluxes in medium frequency pulsed DC magnetron sputtering

“…Asymmetric bipolar power supplies typically give a large fast positive voltage overshoot when switching from its negatively biased "on" state to its positively biased "off" state which raises the plasma potential to a large positive value, producing a rapid expansion of the plasma sheath at the substrate, causing it to be bombarded with ions of very high energy [2,3]. The bombardment of the substrate by these ions may have a significant effect on the growing film, for example, by modifying the film crystallography, removing defects, roughening the surface and enhancing the properties such as adhesion, hardness, wear resistance, frictional resistance, and corrosion resistance [4][5][6][7][8][9]. It was previously shown by energy resolved mass spectrometry that the ion flux to the substrate measured at a position offset from the centre line of the magnetron target gave rise to significant ion bombardment at high energy up to ∼ 250 eV and that the ion flux increased markedly at higher pulse repetition frequencies N250 kHz [10].…”