Coatings and Surface Engineering for Environmental Protection II: Corrosion Control Session II
Sponsored by: TMS Structural Materials Division, TMS: Corrosion and Environmental Effects Committee
Program Organizers: Arif Mubarok, PPG; Raul Rebak, GE Global Research; Rajeev Gupta, North Carolina State University; Tushar Borkar, Cleveland State University; Brian Okerberg, PPG Industries; Michael Mayo, PPG Industries
Wednesday 2:00 PM
February 26, 2020
Room: 19
Location: San Diego Convention Ctr
Session Chair: Arif Mubarok, PPG; Raul Rebak, GE Global Research
2:00 PM Invited
Corrosion Study on CFRP-AZ31B Spot Joined by Friction Self-pierce Rivet: Yong Chae Lim1; Jiheon Jun1; Jian Chen1; Michael Brady1; Donovan Leonard1; Charles Warren1; Zhili Feng1; 1Oak Ridge National Laboratory
Higher specific strength materials, such as magnesium alloys and carbon fiber reinforced composite (CFRP) can be applied for lightweight vehicle applications to improve fuel efficiency. However, joining and corrosion (particularly galvanic corrosion) of these materials are critical technical challenges for this application. In the present work, we attempted a novel friction self-piercing rivet process to spot join a carbon fiber composite to AZ31B with a laboratory coupon scale. Then, we studied the corrosion behavior of this dissimilar joint by 0.1 M NaCl immersion test with different exposure times. Corrosion depth was measured after immersion testing. Lap shear tensile testing was performed to access mechanical joint strength of post-corrosion specimens. Optical and electron microscopy techniques were employed to characterize corroded samples to understand corrosion behavior of CFRP-AZ31B joint.
2:20 PM
Corrosion Challenges in Dissimilar Joint Structures for Automotive Lightweighting: Hyun Wook Ro1; Egle Puodziukynaite1; Loubna Pagnotti1; Fuduo Ma1; Brian Okerberg1; 1Coating Innovation Center, PPG Industries Inc.
Recent coating innovations have opened the door to the use of new low temperature paint processes, which have the potential to reduce energy consumption and improve sustainability in automotive assembly plants. Successful transition to lower temperature bake process is also expected to enable introduction of new, lightweight polymeric materials as a substitute for metal parts, resulting in improved fuel efficiency and sustainability. In this talk, we will present recent efforts in mitigating the corrosion challenges posed by dissimilar material hem joint structures comprised of carbon fiber reinforced polymers (CFRP) and aluminum alloy for lightweight automotive applications.
2:40 PM Invited
Corrosion Behavior of Ultrasonic-welded AZ31B and Dual-phase Steel with and without Galvanized Layer: Jiheon Jun1; Chen Jian1; Yong Chae Lim1; Michael Brady1; Donovan Leonard1; Zhili Feng1; 1Oak Ridge National Laboratory
Application of magnesium (Mg) alloys for autobody structures can reduce the total weight of vehicles, leading to improved fuel efficiency. However, Mg alloys are highly susceptible to corrosion, and the corrosion of Mg alloys can be exacerbated when they are joined with other metals due to the galvanic effect. In this work, a commercial Mg alloy, AZ31B, was ultrasonically welded with dual-phase steels with and without a galvanized Zn layer. The joint area was selectively exposed to the corrosive medium with insulating tape masking in order to focus on the corrosion behavior at the joint of AZ31B and steel. The masked specimens were immersed in 0.1 M NaCl for 24 h and longer, and the corrosion depth of the joint area was measured. Mechanical joint strength of post-corrosion specimens was also assessed using lap shear tensile tests, and the microstructural and chemical analysis on corroded joint area were also conducted.
3:00 PM Invited
First-principles Search for Alloying Elements that Increase Corrosion Resistance of Mg with Transition Metal Impurities: Mingfei Zhang1; Louis Hector Jr.2; Yang Guo3; Ming Liu3; Liang Qi1; 1University of Michigan; 2GM Global Technical Center; 3General Motors R&D China Science Laboratory
A significant challenge for applications of Mg alloys is their poor corrosion resistance, so Mg alloys designs with built-in corrosion resistance are of substantial interest. Corrosion can result from the coupling of anodic dissolution of Mg and cathodic reduction of water on impurities such as Iron (Fe)-rich second-phase particles. Experiments show that small quantities of Arsenic (As) or Germanium (Ge) can inhibit Mg corrosion, possibly slowing the hydrogen evolution reaction (HER) as the cathodic reaction on Fe surfaces. We designed thermodynamic and HER criteria, and used high-throughput computations to search a pool of 68 elements that can segregate from bulk Mg to surfaces of Fe particles and impede HER there. Our computational procedure predicts that only several p-block elements meet these criteria, and As and Ge are the best two alloying elements according to their ability to reduce the HER rate. These results are in qualitative accord with recent experiments.
3:20 PM
Mechanisms of Corrosion Inhibition Afforded by Exfoliated Graphite Nanocomposites: Can Exfoliated Graphite Compete with Graphene?: Rachel Davidson1; Sarbajit Banerjee1; 1Texas A&M University
Chromium-based coatings remain the dominant corrosion-inhibiting technology in the aerospace industry despite the well-documented carcinogenic effects of hexavalent chromium biproducts. Graphene-based coatings offer an intriguing alternative given the ultrathin, impermeable nature of the 2D material. However, galvanic corrosion, limitations in dispersion, and processing challenges have limited its large-scale use. We have explored performance of unfunctionalized exfoliated graphite-polymer composites as a function of exfoliated graphite loading. Mechanisms of corrosion inhibition are understood through combined AC conductivity and electrochemical impedance spectroscopy studies monitoring coatings submerged in saline solutions over 100 days. At low loadings, unfunctionalized exfoliated graphite dispersed in polyetherimide offers excellent protection forming electrically isolated 2D inclusions creating extended tortuous pathways for diffusion of corrosive species, while higher loadings allow for deleterious percolative networks to form resulting in galvanic corrosion.
3:40 PM Break
3:55 PM
Surface Characterization of FeCrAl Accident Tolerant Fuel Cladding Material After Flow Boiling Testing Under Atmospheric Pressure: Rajnikant Umretiya1; Jessika Rojas1; Mark Anderson2; Barret Elward2; Raul Rebak3; Sama Bilbao y Leon1; 1Virginia Commonwealth University; 2University of Wisconsin-Madison; 3GE Global Research
Accident Tolerant Fuels are defined as nuclear fuels that can withstand the loss of active cooling in the core for a considerably longer period of time (and the higher resultant temperatures) than the current UO2/Zr-based cladding fuel system, offering improved coping time under accident conditions. The Critical Heat Flux (CHF) is an important aspect of the thermal hydraulic performance that needs to be investigated to establish safety and operational margins, where materials’ surface parameters have evidence to affect it. This work investigated the surface characteristics of several FeCrAl alloy ATF candidates before and after flow boiling experiments. Roughness parameters were measured by contact profilometry as well as AFM and SEM. After CHF tests the average static contact angle of the specimen dropped by 23% that was confirmed by the liquid spreading method. Furthermore, changes in surface characteristics after CHF testing were conducted through XPS, SEM and EDS, evidencing oxide formation.
4:15 PM
Ceramic Oxide Coatings for Water Reactors: Corrosion Protection in High Temperature Pressurized Water: Mattia Cabrioli1; Erkka Frankberg1; Matteo Vanazzi1; Koba Van Loo2; Jef Vleugels3; Konstantina Lambrinou4; Fabio Di Fonzo1; 1Center for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia; 2KU Leuven, Department. of Materials Engineering; 3KU Leuven, Department of Materials Engineering; 4SCK•CEN
Longer operational life and improved resistance against severe accidents for advanced water-cooled reactors are achievable by coating traditional structural materials, to reduce corrosion rates, improve high temperature oxidation resistance and minimize hydrogen uptake. In the framework of European project IL TROVATORE, ceramic oxides are proposed as protective coatings for Accident Tolerant Fuel (ATF) cladding in the Pressurized Water Reactor (PWR). Materials matching neutronic requirements and chemical stability in PWR environment are produced as sintered pellets, and as thin films by the Pulsed Laser Deposition (PLD) technique. After exposure to pure water at 360°C and saturation pressure, simulating PWR core during normal operation, detected mass changes are correlated to superficial and structural modifications. Best candidate oxide, grown on relevant substrates (Zirconium-based alloys and AISI316L) by optimized PLD process, proves effective protection and significant reduction of substrate oxidation, hence promoting PLD as viable technique to produce high-performance, strongly adherent ceramic films.
4:35 PM
Fatigue Corrosion Behavior of NiTi Shape Memory Alloy: Mahdi Mohajeri1; Dimitris C Lagoudas1; Homero Castaneda1; 1Texas A&M University
The fatigue process causes the protective passive film rapture, which accelerates the corrosion of metallic materials. The synergic interaction of fatigue and corrosion processes with variable thermal and mechanical loads cause the shorter fatigue lifetime. In this study, the thermomechanical fatigue of Nickel-Titanium shape memory alloy (SMA) undergoing thermally induced martensitic phase transformation in a physiological corrosive environment is investigated. The effect of the change in phases of Nickel-Titanium SMA on the electrochemical behavior at different load levels was characterized. Electrochemical techniques showed the global influence on the SMA surface during the change in crystallographic orientation and phase transformation due to the loading conditions. This change in crystallographic orientation affected the surface of Nickel-Titanium SMA locally. These local effects could be sensed by the global interfacial changes with electrochemical measurements, such as Electrochemical Impedance Spectroscopy (EIS), Open Circuit potential (OCP) and Linear polarization (LPR) methods.
4:55 PM
Can Proteins Secreted by Barnacles Corrode Marine-grade Steel?: Vinod K. Murugan1; Harini Mohanaram1; Maja Budanovic1; Arvind Latchou1; Richard Webster1; Enrico Marsili2; Ali Miserez1; Matteo Seita1; 1Nanyang Technological University; 2Nazarbayev University
Barnacle adhesion on steel in marine applications is enabled by the protein-based cement that the crustacean secretes, which results in metal corrosion. Despite its economic and safety repercussions, very little is known about the mechanisms behind this protein-influenced corrosion (PIC) process. In this work, we investigate PIC by comparing the electrochemical processes at play when a marine grade steel is exposed to different proteins, including CP20, bovine serum albumin and lysozyme. Our results show that PIC is function of the absorptivity of proteins to the steel surface, which points to adsorption-induced chemical dissolution of iron as the PIC mechanism. These findings play a critical role in the design and formulation of solutions for corrosion prevention.