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Synthesis of Novel DLC Films
Published in Peerawatt Nunthavarawong, Sanjay Mavinkere Rangappa, Suchart Siengchin, Kuniaki Dohda, Diamond-Like Carbon Coatings, 2023
A. Chingsungnoen, P. Poolcharuansin
High power impulse magnetron sputtering or HiPIMS has been introduced as a novel thin film deposition technique by Kouznetsov et al. in 1999 (Kouznetsov et al. 1999). In HiPIMS discharge, the pulses of negative voltage ranged from 900 V up to 1600 V is applied to the sputtering magnetron, resulting in the target peak current and power density of up to 5 Acm-2 and 2.8 kWcm-2, respectively. The discharge parameters employed in HiPIMS are approximately two orders of magnitude higher than those used in the conventional direct current magnetron sputtering (DCMS) (Gudmundsson et al. 2012). Using extremely high power density, the plasma concentration adjacent to the magnetron target is considerably increased to the range of 1018–1019 m-3, comparing to that of 1016 m-3 in DCMS discharge. As a result, the ionization rate of the sputtered species can be significantly enhanced, increasing the contribution of the metal ions in the discharge phenomena and the thin film processes. To keep the average power at the target lower than the power limit, HiPIMS is typically operated in the pulse mode with a low repetition rate (50–5000 Hz) and a low duty cycle (0.5–5%) (Gudmundsson and Lundin 2020).
Thin Film Materials for Energy Applications
Published in Fredrick Madaraka Mwema, Tien-Chien Jen, Lin Zhu, Thin Film Coatings, 2022
Fredrick Madaraka Mwema, Tien-Chien Jen, Lin Zhu
These thin film alloys are formed through High power impulse magnetron sputtering (HiPIMS). The resulting thin film coating is annealed at a high temperature to produce a very stable coating [39]. A study that was conducted by Qingsong Chen et al. showed that FeCrMnNi HEA could also be used as ATF since it possesses very good radiation hardness. They also researched on CrCuFeMoNi deposited through magnetron sputtering, and they discovered that it is superior in hardness and high temperature corrosion resistance due to Cr2O3 and FeCr2O4 layer. This makes it suitable for use as ATF in nuclear reactors [40]. HfNbTiVZr is another HEA researched by Stefan Fritze et al. [41], and thin films were deposited through the DC-magnetron sputtering method [41]. With this alloy, it is possible to obtain different microstructure thin films in the form of amorphous, single-phase BCC, or dual-phase which possess different mechanical properties.
Techniques, Trends, and Advances in Conventional Machining Practices for Metals and Composite Materials
Published in T. S. Srivatsan, T. S. Sudarshan, K. Manigandan, Manufacturing Techniques for Materials, 2018
Ramanathan Arunachalam, Sathish Kannan, Sayyad Zahid Qamar
Nanolayered physical vapor deposited titanium aluminium nitride coatings with a titanium/aluminium ratio of 46/54 were deposited on carbide tools using high power impulse magnetron sputtering (Skordaris et al. 2016). The coating structure consisted of successive nanolayers of titanium aluminium nitride (24 nm) and titanium nitride layers (3 nm) amounting to a total thickness of 2, 4, and 8 μm. The nanolayered coated tools exhibited improved wear resistance compared to a single layer of the same thickness when milling hardened steels at high cutting speeds. The highest thickness (8 μm) performed the best, yielding a tool life of almost 365,000 cuts. The better performance of nanolayer coatings when compared to multilayer and single layer coatings is due to the large number of interfaces, which act as inhibitors of crack propagation (Caliskan et al. 2013). Such coatings exhibit good mechanical properties, such as (a) hardness, (b) toughness, and (c) adhesion. The performance of nanolayer-aluminium titanium nitride/titanium nitride and multilayer nanocomposite titanium aluminium silicon nitride/titanium silicon nitride/titanium aluminium nitride coated carbide tools during high-speed machining of hardened steel was evaluated by Halil Caliskan and coworkers (Caliskan et al. 2013). The nanolayer coated tool performed the best among the compared tools and its tool life was 25, 77 and 2300% of that of the nanocomposite, commercial titanium nitride/titanium aluminium nitride coated and uncoated tools, respectively. The high-temperature hardness exhibited by nanostructured aluminium0.8 titanium0.2 nitride coating enabled an increase in productivity of 400% when machining steels and cast irons (Köpf et al. 2017).
A comprehensive review of vapour deposited coatings for cutting tools: properties and recent advances
Published in Transactions of the IMF, 2022
N. Ariharan, C. G. Sriram, N. Radhika, S. Aswin, S. Haridas
Direct Current Magnetron Sputtering (DCMS) is a line-of-sight deposition process that involves the formation of a glow discharge through the application of a Direct Current between the cathode (target material) and the anode (substrate) to ionise the gaseous atoms present in the chamber. These ions are then bombarded onto the target surface at high velocities causing the atoms of the target material to dislodge which, in turn, travel across the chamber to get deposited onto the substrate surface. Coatings deposited through DCMS usually follow a loosely packed columnar morphology.35, 38 One of the major drawbacks of DCMS is that only electrically conductive materials can be used as the target material.38 Radio Frequency (RF) sputtering is a deposition process that takes place in a vacuum environment. It involves the use of an Alternating Current (AC) source to sputter the target material during every positive cycle and to reduce the charge build ups on the target surface during the negative cycles. As this method involves an AC source, it produces a far denser plasma region when compared to a DC source (about four times denser). This plasma region extinguishes at every half cycle and must be re-generated.52 Unlike DCMS, RF sputtering can be used to deposit non-conductive materials.53 High Power Impulse Magnetron Sputtering (HiPIMS) is a sputtering technique similar to the conventional DCMS; however, this method involves the usage of a very high pulse peak power (around 2–3 times the magnitude used in DCMS) over lower duty cycles on top of the target material (Cathode).54 During discharge, the peak power densities can vary from 0.5–10 kW cm-2. 38, 54 HiPIMS, in comparison to DCMS, has far higher ionisation rates and the coatings deposited through HiPIMS show a denser, smoother, and uniform structural morphology.54, 55 Although the ionisation rate is generally far higher in HiPIMS, the deposition rate and control over the thickness of the deposited layers are relatively low when compared to DCMS under similar conditions.56, 57Table 1 compares some of the important vapour deposition methods.