Title: Effects of Film Thickness of ALD-Deposited Al2O3, ZrO2 and HfO2 Nano-Layers on the Corrosion Resistance of Ti(N,O)-Coated Stainless Steel
The goal of this stydy was to explore the potential of the enhanced corrosion resistance of Ti(N,O) cathodic arc evaporation-coated 304L stainless steel using oxide nano-layers deposited by atomic layer deposition (ALD). In this study, we deposited Al2O3, ZrO2, and HfO2 nanolayers of two different thicknesses by ALD onto Ti(N,O)-coated 304L stainless steel surfaces. XRD, EDS, SEM, surface profilometry, and voltammetry investigations of the anticorrosion properties of the coated samples are reported. The amorphous oxide nanolayers homogeneously deposited on the sample surfaces exhibited lower roughness after corrosion attack compared to the Ti(N,O)-coated stainless steel. The best corrosion resistance was obtained for the thickest oxide layers. All samples coated with thicker oxide nanolayers augmented the corrosion resistance of the Ti(N,O)-coated stainless steel in a saline, acidic, and oxidising environment (0.9% NaCl + 6% H2O2, pH = 4), which is of interest for building corrosion-resistant housings for advanced oxidation systems such as cavitation and plasma-related electrochemical dielectric barrier discharge for breaking down persistent organic pollutants in water. more »« less
Daroonparvar, Mohammadreza; Kasar, Ashish K.; Farooq Khan, Mohammad Umar; L. Menezes, Pradeep; Kay, Charles M.; Misra, Manoranjan; Gupta, Rajeev K.(
, Coatings)
null
(Ed.)
In this study, a compact cold sprayed (CS) Ti coating was deposited on Mg alloy using a high pressure cold spray (HPCS) system. The wear and corrosion behavior of the CS Ti coating was compared with that of CS Al coating and bare Mg alloy. The Ti coating yielded lower wear rate compared to Al coating and Mg alloy. Electrochemical impedance spectroscopy (EIS) and cyclic potentiodynamic polarization (CPP) tests revealed that CS Ti coating can substantially reduce corrosion rate of AZ31B in chloride containing solutions compared to CS Al coating. Interestingly, Ti-coated Mg alloy demonstrated negative hysteresis loop, depicting repassivation of pits, in contrast to AZ31B and Al-coated AZ31B with positive hysteresis loops where corrosion potential (Ecorr) > repassivation potential (Erp); indicating irreversible growth of pits. AZ31B and Al-coated AZ31B were most susceptible to pitting corrosion, while Ti-coated Mg alloy indicated noticeable resistance to pitting in 3.5 wt % NaCl solution. In comparison to Al coating, Ti coating considerably separated the AZ31BMg alloy surface from the corrosive electrolyte during long term immersion test for 11 days.
Limongelli, Maria Pina; Ng, Ching Tai; Glisic, Branko
(Ed.)
Civil engineering structures are routinely exposed to corrosive environments, posing threats to their structural integrity. Traditional corrosion control methods often involve employing physical barriers, such as various coatings, to isolate the steel substrate from surrounding electrolytes. Among these methods, thermal spraying of alloy coatings has emerged as a prominent technique in safeguarding steel matrices against corrosion, particularly in industrial and marine settings. However, the inherent porosity of thermal spraying coatings compromises their corrosion resistance. Incorporating a polymer top layer offers a promising solution by sealing pores and augmenting overall performance. This study investigates corrosion on duplex-coated steel utilizing distributed fiber optic sensors based on optical frequency domain reflectometry. Experimental analyses involve embedding serpentine-arranged distributed fiber optic strain sensors within both thermal spraying layers and epoxy layers. Results demonstrate the efficiency of distributed sensors in identifying corrosion propagation paths by measuring the induced strain changes. Furthermore, the duplex coating exhibits significant enhancements in corrosion resistance for steel structures.
Sanchez, Pablo; Tyagi, Pawan(
, American Society of Mechanical Engineers)
Abstract
The current study investigates electroless nickel plating and surface finishing techniques such as ChemPolishing (CP) and ElectroPolishing (EP) for postprocessing on additively manufactured stainless-steel samples. Existing additive manufacturing (AM) technologies generate metal components with a rough surface that typically exhibit fatigue characteristics, resulting in component failure and undesirable friction coefficients on the printed part. Small cracks formed in rough surfaces at high surface roughness regions act as a stress raiser or crack nucleation site. As a result, the direct use of as-produced parts is limited, and smoothening the Surface presents a challenge. Previous research has shown that CP ChemPolishing has a significant advantage in producing uniform, smooth surfaces regardless of size or part geometry. EP Electropolishing has a high material removal rate and an excellent surface finishing capability. Electropolishing, on the other hand, has some limitations in terms of uniformity and repeatability. On additively manufactured stainless-steel samples, electroless nickel deposition has a higher plating potential. Nickel has excellent wear resistance, and nickel-plated samples are more robust as scratch resistant than not plated samples when tested for scratch resistance. This research uses medium-phosphorus (6–9% P) and high-phosphorus (10–13% P). The L9 Taguchi design of experiments (DOE) was used to optimize the electroless nickel deposition experiments. The mechanical properties of as-built and nickel-coated additive manufacturing (AM) samples were investigated using a standard 5 N scratch test and the adhesion test ASTM B-733 thermal shock method. The KEYENCE Digital Microscope VHX-7000 was used to examine the pre- and post-processed surfaces of the AM parts. The complete scratch and Design of Experiment (DOE) analysis was performed using the Qualitek-4 software. This work is in progress concerning testing the optimum conditions, completing measurements, and analyzing the results.
Abstract In this study, a superhydrophobic and superoleophilic stainless mesh coated with polytetrafluoroethylene/silicon dioxide (PTFE/SiO 2 ) was fabricated through electrostatic self-assembly method followed by sintering treatment. The PTFE was utilized to construct low-surface-energy surface and the SiO 2 nanoparticles were added to enhance its surface roughness. The as-prepared stainless mesh exhibited desirable superhydrophobicity and superoleophilicity with a water contact angle of 152° and oil contact angle of 0°. The coated stainless mesh could separate a variety of oil/water mixtures with high efficiency and it also exhibited good recyclability. Moreover, the corrosion-resistance of stainless mesh was greatly improved by coating it with PTFE. The thermogravimetric analysis (TGA) measurements showed that the coated mesh could withstand high temperature of up to 430°C, indicating excellent thermal-resistance. It is believed that this ultra-robust stainless mesh would have significant potential applications in industry.
Heterogeneous bonding between metals and ceramics is of significant relevance to a wide range of applications in the fields of industry, defense, and aerospace. Metal/ceramic bonding can be used in various specific part applications such as vacuum tubes, automotive use of ceramic rotors, and rocket igniter bodies. However, the bonding of ceramic to metal has been challenging mainly due to (1) the low wettability of ceramics, on which the adhesion of molten adhesive bonders is limited and (2) the large difference between the coefficients of thermal expansion (CTE) of the two dissimilar bonded materials, which develops significant mechanical stresses at the interface and potentially leads to mechanical failures. Vapor-phase deposition is a widely used thin film processing technique in both academic research laboratories and manufacturing industries. Since vapor phase coatings do not require wettability or hydrophobicity, a uniform and strongly adherent layer is deposited over virtually any substrate, including ceramics. In this presentation, we report on the effect of vapor phase-deposited interfacial metal layers on the mechanical properties of bonding between stainless steel and Zerodur (lithium aluminosilicate-based glass ceramic). Direct-current magnetron sputtering was utilized to deposit various thin interfacial layers containing Ti, Cu, or Sn. In addition, to minimize the unfavorable stress at the bonded interface due to the large CTE difference, a low temperature allow solder, that can be chemically and mechanically activated at temperatures of approximately 200 °C, was used. The solder is made from a composite of Ti-Sn-Ce-In. A custom-built fixture and universal testing machine were used to evaluate the bonding strength in shear, which was monitored in-situ with LabView throughout the measurement. The shear strength of the bonding between stainless steel and Zerodur was systematically characterized as a function of interfacial metal and metal processing temperature during sputter depositions. Maximum shear strength of the bonding of 4.36 MPa was obtained with Cu interfacial layers, compared to 3.53 MPa from Sn and 3.42 MPa from Ti adhesion promoting layers. These bonding strengths are significantly higher than those (~0.05 MPa) of contacts without interfacial reactive thin metals. The fracture surface microstructures are presented as well. It was found that the point of failure, when Cu interfacial layers were used, was between the coated Cu film and alloy bonder. This varied from the Sn and Ti interfacial layers where the main point of failure was between the interfacial film and Zerodur interface. The findings of the effect of thin adhesion promoting metal layers and failure behaviors may be of importance to some metal/ceramic heterogeneous bonding studies that require high bonding strength and low residual stresses at the bonding interface. The authors gratefully acknowledge the financial support of the Improvement of Measurement Standards and Technology for Mechanical Metrology (Grant No. 20011028) by KRISS.
Dinu, Mihaela, Wang, Kaiying, Mouele, Emile S., Parau, Anca C., Vladescu, Liang, Xinhua, Braic, Viorel, Petrik, Leslie Felicia, and Braic, Mariana. Effects of Film Thickness of ALD-Deposited Al2O3, ZrO2 and HfO2 Nano-Layers on the Corrosion Resistance of Ti(N,O)-Coated Stainless Steel. Retrieved from https://par.nsf.gov/biblio/10442353. Materials 16.5 Web. doi:10.3390/ma16052007.
Dinu, Mihaela, Wang, Kaiying, Mouele, Emile S., Parau, Anca C., Vladescu, Liang, Xinhua, Braic, Viorel, Petrik, Leslie Felicia, and Braic, Mariana.
"Effects of Film Thickness of ALD-Deposited Al2O3, ZrO2 and HfO2 Nano-Layers on the Corrosion Resistance of Ti(N,O)-Coated Stainless Steel". Materials 16 (5). Country unknown/Code not available. https://doi.org/10.3390/ma16052007.https://par.nsf.gov/biblio/10442353.
@article{osti_10442353,
place = {Country unknown/Code not available},
title = {Effects of Film Thickness of ALD-Deposited Al2O3, ZrO2 and HfO2 Nano-Layers on the Corrosion Resistance of Ti(N,O)-Coated Stainless Steel},
url = {https://par.nsf.gov/biblio/10442353},
DOI = {10.3390/ma16052007},
abstractNote = {The goal of this stydy was to explore the potential of the enhanced corrosion resistance of Ti(N,O) cathodic arc evaporation-coated 304L stainless steel using oxide nano-layers deposited by atomic layer deposition (ALD). In this study, we deposited Al2O3, ZrO2, and HfO2 nanolayers of two different thicknesses by ALD onto Ti(N,O)-coated 304L stainless steel surfaces. XRD, EDS, SEM, surface profilometry, and voltammetry investigations of the anticorrosion properties of the coated samples are reported. The amorphous oxide nanolayers homogeneously deposited on the sample surfaces exhibited lower roughness after corrosion attack compared to the Ti(N,O)-coated stainless steel. The best corrosion resistance was obtained for the thickest oxide layers. All samples coated with thicker oxide nanolayers augmented the corrosion resistance of the Ti(N,O)-coated stainless steel in a saline, acidic, and oxidising environment (0.9% NaCl + 6% H2O2, pH = 4), which is of interest for building corrosion-resistant housings for advanced oxidation systems such as cavitation and plasma-related electrochemical dielectric barrier discharge for breaking down persistent organic pollutants in water.},
journal = {Materials},
volume = {16},
number = {5},
author = {Dinu, Mihaela and Wang, Kaiying and Mouele, Emile S. and Parau, Anca C. and Vladescu and Liang, Xinhua and Braic, Viorel and Petrik, Leslie Felicia and Braic, Mariana},
}
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