Advances in Surface Engineering IV: On-Demand Oral Presentations
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Surface Engineering Committee
Program Organizers: Arif Mubarok, PPG; Bharat Jasthi, South Dakota School of Mines & Technology; Tushar Borkar, Cleveland State University; Mary Lyn Lim, PPG Industries; Rajeev Gupta, North Carolina State University
Monday 8:00 AM
March 14, 2022
Room: Materials Processing
Location: On-Demand Room
Effect of Laser Surface Treatment on Corrosion Behavior of AZ91D Mg Alloy: Jiheon Jun1; Gerald Knapp1; Alex Plotkowski1; Donovan Leonard1; Yong Chae Lim1; Michael Brady1; 1Oak Ridge National Laboratory
Magnesium (Mg) alloys are promising lightweight materials for vehicle applications to improve energy efficiency. However, galvanic corrosion of Mg alloys joined with dissimilar metals remains a major technical challenge. As a viable corrosion mitigation approach, laser treatment on AZ91D Mg alloy surface was attempted with varying laser processing parameters to locally modify the surface chemical composition and form an O- and Al-rich surface layer. The aim of this work is to develop laser surface treatment with the guidance of numerical modeling and to verify the corrosion mitigation effect of laser-treated AZ91D surfaces. Electrochemical corrosion evaluation of laser-treated AZ91D will be conducted, and the results will be reported and discussed in this presentation. The laser-treated AZ91D samples will also be characterized to investigate the chemical compositions and microstructural evolutions on the surface and in the sub-surface region.
Atmospheric Plasma Surface Processing of a 7xxx Al Alloy Surface to Improve Corrosion Resistance: Yong Chae Lim1; Jiheon Jun1; Donovan Leonard1; Harry Meyer III1; Jong Kahk Keum1; Michael Brady1; Zhili Feng1; 1Oak Ridge National Laboratory
High strength aluminum (Al) alloys are candidate lightweight materials for applications in transportation sectors. However, general and/or galvanic corrosion of 7xxx series Al alloys remain as technical challenges. In the present work, we applied atmospheric plasma processing to a 7xxx Al alloy surface in attempt to grow a ceramic oxide (such as Al2O3) layer or change local composition of the near surface to improve its corrosion resistance. Electrochemical measurements were conducted on the Al alloys before and after surface processing to demonstrate the improvement of corrosion resistance. Then, analytical electron microscopy and surface chemical analysis were used to elucidate more details of the modified surface.
Intermetallic Formation in High-temperature Al/Ni Wetting: A Molecular Dynamics Study: Ensieh Yousefi1; Youqing Sun1; Anil Kunwar2; Muxing Guo1; Nele Moelans1; David Seveno1; 1KU Leuven; 2Silesian University of Technology
Wetting process at high temperatures is an inherently complex mechanism that requires nanoscale study for better understanding. Molecular dynamics simulations were therefore performed to investigate the spreading process of a liquid Aluminum droplet on solid Nickel substrate at 1023.15 K. As revealed from the Aluminum-Nickel phase diagram, the reactions between Aluminum and Nickel result in the formation of various intermetallics depending on the temperature and composition. The structure of each intermetallic compound was studied separately. The interfacial reaction products in the spreading were identified by benchmarking their properties with intermetallics outlined in the Aluminum-Nickel phase diagram. The spreading was fast at the very beginning and no intermetallics were detected. As the wetting time progresses, the spreading rate decreased and Aluminum richer intermetallics formed but gradually transformed into Nickel richer intermetallics. At the end, Al3Ni5 and AlNi3 were the dominant intermetallics in the substrate while AlNi was found in the droplet.
Damage Evolution of HVOF Coatings under Shear Lag Test: Deepesh Yadav1; Sanjay Sampath1; Jaya Balila1; 1IIT Bombay
This study investigated damage evolution i.e. surface cracking and delamination of metallic Ni-based coatings deposited by high-velocity oxy-fuel (HVOF), under shear lag test by using experimental and numerical methods. Experimental results revealed that Ni and Ni-5Al coatings get delaminated when 0.05 and 0.027 strain is reached in substrate respectively and no surface cracking occurs in coatings throughout the test while in NiCrAlY coating surface crack forms at 0.016 strain and delamination of coating starts at 0.035 strain in substrate. Full-scale strain distribution in coatings has been determined by digital image correlation, and stress in coatings and substrate has been determined by using FEM. The cohesive strength of Ni and Ni-5Al coatings are better than NiCrAlY coating while adhesive strength of NiCrAlY coating is better than Ni and Ni-5Al coatings.
Multi-objective Machine Learning Assisted Optimization of Multi-layered PVD Coatings: Aida Amroussia1; Andrew Detor1; Scott Weaver1; Patrick Shower1; Anteneh Kebbede1; Andrew Hoffman1; Raul Rebak1; 1GE Global Research
To increase the reliability and safety of existing fossil, biomass, and nuclear power plants, it is necessary to develop cost-effective coatings that provide improved wear and corrosion resistance in high temperature water and steam environments. Physical vapor deposition (PVD) coatings are widely used in different industries due to their scalability and good performance. A large number of intertwined processing parameters such as voltage, pressure, carrier gas flow and target composition influence the resulting PVD coating microstructure, thickness, and performance. In this study, we leverage advances in machine learning to optimize the deposition parameters of our novel multi-layered PVD coatings (based on high-strength ceramics and metals). The results of our multi-objective optimization approach (microstructural features, solid particle erosion and steam oxidation resistance) will be presented and discussed in the context of improving overall system performance.
Ternary Transition Metal Diborides: A New Generation of Protective Coating Materials?
: Anna Hirle1; Christoph Fuger1; Ahmed Bahr1; Thomas Glechner1; Lukas Zauner1; Oliver Hudak1; Rainer Hahn1; Oliver Hunold2; Peter Polcik3; Helmut Riedl4; 1Christian Doppler Laboratory for Surface Engineering of high-performance Components, TU Wien; 2Oerlikon Surface Solutions AG; 3Plansee Composite Materials GmbH; 4TU Wien, Institute of Materials Science and Technology
Future high-performance components used in aviation and energy production require customized protective coating materials to fulfil specific criteria on efficiency as well as durability. Next to the well-established nitride-based coatings are boron containing systems an upcoming and highly promising class. Here, ternary transition metal diborides are relatively unexplored compared to their binary counterparts such as hard and inelastic TiB2. Typically, these boride-based coatings are limited by their brittle behaviour as well as volatile oxide scale formation. Within this study, we want to address these specific challenges on various ternary model systems within group IV to VI transition metal diborides (e.g. M1-xMxB2-z prototypes). The phase formation of the two competing hexagonal structure types (α AlB2 vs. ω-W2B5-x) has been investigated for various PVD based deposition routes. In addition, different alloying concepts for enhancing the ductile character as well as oxidation resistance of these superhard ternary diborides will be discussed in detail.
An Investigation of the Microstructure and Oil Retention of Electrolyte Jet Plasma Oxidation (EJPO) Coating: Nasim Bahramian1; Sina Kianfar1; Joshua Stroh1; Dimitry Sediako1; Jimi Tjong2; 1The University of British Columbia; 2University of Windsor
Next-generation automotive engines demand new materials and technologies to meet efficiency mandates regarding energy conservation and emission reduction. Replacing heavy ferrous metals with lightweight aluminum (Al) alloys can considerably improve fuel efficiencies in the transportation sector. However, most Al alloys suffer from poor tribological characteristics, which urged original equipment manufacturers to develop advanced materials for high friction applications like cylinder blocks. Recently, there has been a growing trend to produce coatings with high-temperature strength and wear-resistance. These coatings are deposited on an Al substrate of linerless engine blocks using various technologies, including Electrolytic Jet Plasma Oxidation (EJPO). The present study investigates the coating’s microstructure, surface roughness, and oil retention and compares the latter with the oil retention of the Plasma Transferred Wire Arc (PTWA) coating which is currently used in cylinder block applications. The results revealed higher roughness (Ra=0.86 µm) and oil retention (V0=0.356 μm3/μm2) of the EJPO coating than the PTWA one (Ra=0.34 µm, V0=0.041 μm3/μm2).
Electrochemical Corrosion Tests of Aluminum 1100 Alloy Coupons in Acid Condensate Environment: Vasundhara Shinde1; Gaurav Argade2; Anusha Chilukuri2; Monica Gehrich2; Chirag Parikh1; 1Cummins Filtration Inc.; 2Cummins Inc.
In this study, product validation tests were compared with rapid electrochemical tests in diesel exhaust condensate environments. Al1100 alloy coupons were exposed to elevated temperature cycles in an acid condensate environment (simulating diesel exhaust conditions) for 36 days, followed by room temperature electrochemical tests. Day 10 coupons showed the lowest corrosion rates which are attributed to formation of protective aluminum hydroxide layer. In the potentiodynamic test, day 10 coupons showed least anodic current densities at +200 mV vs Ag/AgCl and nobler corrosion potentials as compared to day 36 coupons. A similar trend of lower frequency impedance was observed in electrochemical impedance spectroscopy (EIS) scans between 10-2 to 105 Hz. In the post-corrosion examination, pitting on coupons was confirmed along with higher wt.% oxygen measured through Energy-dispersive X-ray spectroscopy, and the corrosion rate increase after 10 days is attributed to eventual degradation of the aluminum hydroxide layer.
An Electrochemical Study of Ferrous and Nonferrous Materials in an Engine Coolant Environment: Gaurav Argade1; Anusha Chilukuri1; Justin Perry1; Monica Gehrich1; Erica Raisor1; Corey Trobaugh1; 1Cummins Inc.
A study was conducted to identify the threshold concentrations of chloride contaminant in an inhibited engine coolant on three different metallic substrates – cast iron, cast aluminum and brass. All three metallic systems showed a reduction in the breakdown potentials during potentiodynamic polarization carried out with increasing chloride concentrations from 0 to 1000 ppm. Higher anodic current densities and lower breakdown potentials were observed for cast aluminum at 1000 ppm chloride concentration compared to the other two metals. However, intermittent electrochemical testing of the immersion tested cast Al and cast iron samples at 90C in inhibited coolants containing up to 2000 ppm Cl additions, showed increased corrosion resistance of cast Al (~ 2.5 orders of magnitude lower corrosion currents and anodic currents) compared to cast Fe. SEM analysis showed that localized trenching around the graphite flakes resulted in high anodic current densities and low breakdown potentials for cast Fe.