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1. Discharge Resistant Nano-Coatings

   https://doi.org/10.1109/CEIDP.2018.8544889  

   Xia, Jing; Li, Zhengyu; Nasreen, Shamima; Ronzello, JoAnne; Teng, Henry; Jacobs, Linda; Cao, Yang (October 2018, 2018 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP))
2. CHARACTERIZATION OF LATERAL FRICTION SURFACED AA6063 COATINGS

   Seidi, E.; Miller, S. (October 2021, International Mechanical Engineering Congress & Exposition)

   Friction surfacing is a solid-state metal deposition technique suitable for a wide range of metallic materials. This technique results in coatings on surfaces for joining purposes or surface modification applications such as wear and corrosion performance improvements. In this study, a novel approach in friction surfacing is utilized in which the consumable tool deposits material from its side instead of the end of the tool, which has been employed in conventional friction surfacing. Frictional heat enables plastic deformation, which results in the depositing of the consumable material on the substrate surface. The process is carried out at temperatures below the melting point of the consumable material, resulting in a solid-state deposition process. In the current study, scanning electron microscopy and energy dispersive spectroscopy have been employed for the characterization of the interfaces and coatings. The results of this study exhibited that there is no elemental diffusion between the tool and substrate materials at the interface, showing that the process temperature was low enough to prevent plasticizing of the substrate surface. 

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3. Comprehensive topography characterization of polycrystalline diamond coatings

   https://doi.org/10.1088/2051-672X/abe71f  

   Gujrati, Abhijeet; Sanner, Antoine; Khanal, Subarna R.; Moldovan, Nicolaie; Zeng, Hongjun; Pastewka, Lars; Jacobs, Tevis D. B. (March 2021, Surface Topography: Metrology and Properties)

   Abstract The surface topography of diamond coatings strongly affects surface properties such as adhesion, friction, wear, and biocompatibility. However, the understanding of multi-scale topography, and its effect on properties, has been hindered by conventional measurement methods, which capture only a single length scale. Here, four different polycrystalline diamond coatings are characterized using transmission electron microscopy to assess the roughness down to the sub-nanometer scale. Then these measurements are combined, using the power spectral density (PSD), with conventional methods (stylus profilometry and atomic force microscopy) to characterize all scales of topography. The results demonstrate the critical importance of measuring topography across all length scales, especially because their PSDs cross over one another, such that a surface that is rougher at a larger scale may be smoother at a smaller scale and vice versa. Furthermore, these measurements reveal the connection between multi-scale topography and grain size, with characteristic scaling behavior at and slightly below the mean grain size, and self-affine fractal-like roughness at other length scales. At small (subgrain) scales, unpolished surfaces exhibit a common form of residual roughness that is self-affine in nature but difficult to detect with conventional methods. This approach of capturing topography from the atomic- to the macro-scale is termedcomprehensive topography characterization, and all of the topography data from these surfaces has been made available for further analysis by experimentalists and theoreticians. Scientifically, this investigation has identified four characteristic regions of topography scaling in polycrystalline diamond materials. 

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4. Corrosion Resistance of Sulfur–Selenium Alloy Coatings

   https://doi.org/10.1002/adma.202104467  

   Susarla, Sandhya; Chilkoor, Govinda; Kalimuthu, Jawahar_R; Saadi, M_A_S_R; Cui, Yufei; Arif, Taib; Tsafack, Thierry; Puthirath, Anand_B; Sigdel, Pawan; Jasthi, Bharat; et al (October 2021, Advanced Materials)

   Abstract Despite decades of research, metallic corrosion remains a long‐standing challenge in many engineering applications. Specifically, designing a material that can resist corrosion both in abiotic as well as biotic environments remains elusive. Here a lightweight sulfur–selenium (S–Se) alloy is designed with high stiffness and ductility that can serve as an excellent corrosion‐resistant coating with protection efficiency of ≈99.9% for steel in a wide range of diverse environments. S–Se coated mild steel shows a corrosion rate that is 6–7 orders of magnitude lower than bare metal in abiotic (simulated seawater and sodium sulfate solution) and biotic (sulfate‐reducing bacterial medium) environments. The coating is strongly adhesive, mechanically robust, and demonstrates excellent damage/deformation recovery properties, which provide the added advantage of significantly reducing the probability of a defect being generated and sustained in the coating, thus improving its longevity. The high corrosion resistance of the alloy is attributed in diverse environments to its semicrystalline, nonporous, antimicrobial, and viscoelastic nature with superior mechanical performance, enabling it to successfully block a variety of diffusing species. 

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5. Ultrasonic nondestructive evaluation of additively manufactured wear coatings

   https://doi.org/10.1016/j.ndteint.2022.102754  

   Smoqi, Ziyad; Sotelo, Luz D.; Gaikwad, Aniruddha; Turner, Joseph A.; Rao, Prahalada (January 2023, NDT & E International)