Advanced Materials for Harsh Environments: Session V
Sponsored by: ACerS Electronics Division
Program Organizers: Navin Manjooran, Solve; Gary Pickrell, Virginia Tech
Wednesday 2:00 PM
October 20, 2021
Room: A224
Location: Greater Columbus Convention Center
Session Chair: James Earthman, University of California-Irvine; Navin Manjooran, Solve
2:00 PM
Corrosion Behaviors of Alloys in High Temperature Supercritical CO2 with Impurity: Yimin Zeng1; Kaiyang Li1; 1NRCan, Canada
The selection of appropriate constructional alloys for compact heat exchangers and joints is a critical material technology challenge on the successful deployment and long-term safe operation of the supercritical CO2 (s-CO2) Brayton cycle in advanced power generation systems. In this study, the corrosion behavior of Alloy 617 was investigated in s-CO2 streams with impurity at 600 oC and 30 MPa for up to 1000 h. The chemical composition and morphology of the formed surface corrosion products are characterized by optical images, X-ray diffraction, SEM, TEM. It is found that the main corrosion product is Cr2O3 and the corrosion mode includes both general oxidation and nodules corrosion. The effect of impurity on oxidation and carburization are also discussed. In all, the alloy shows an acceptable degradation rate, indicating the potential application in Brayton cycle.
2:20 PM
Assessment of Conductive Sites on Carbon Fiber Reinforced Polymer Composite Using Different Electrochemical Experimental Methods: Priyanka Adapala1; 1The Ohio State University
Light metals and composite materials are being adopted by the automotive industry to improve fuel efficiency. Closure panels made from Al alloy and carbon fiber reinforced polymer (CFRP) are being considered as a replacement for the standard all-steel design. A concern is that galvanic contact between the two materials will accelerate Al corrosion. The carbon fiber fillers are noble and conductive but are protected by the polymer matrix. However, the polymer cover is non-uniform due to various process variables. Any exposed fibers can be strong cathodes in a galvanic couple with Al, resulting in accelerated dissolution of Al. Rotating disk electrode experiments are performed to evaluate the kinetics of the electrochemical active sites and Cu electrodeposition is performed to locate and quantify conductive sites on CFRP. The observations are correlated with electrochemical behavior of CFRP.
2:40 PM
The Importance of Quality Control, Characterization and Testing in Manufacturing and Production: Jeanette Vass1; 1Auto and Materials
My talk will raise awareness of a widespread problem that endangered homeowners In the Southeastern United States to a price tag of over a billion dollars. I will detail the vital importance of the following very critical measures: * Having a Proper Quality Control Plan with Materials Characterization and Testing * Controlled Distribution of Domestic and Imported Goods and MaterialsThis presentation will demonstrate the very serious Consequences when Quality Control and Testing Protocols are lacking or not followed. This case represented more than 100,000 affected homes where the interior environment became dangerously toxic along with causal environmental factors important to a devastating failure. With accurately identified reason(s) for the problem, I will attest the value of a systematic analytical characterization approach through applied and integrated use of standard and micro-scale spectroscopic tools in failure analysis (e.g., FT-IR, SEM/EDS, XPS, & more). Practical solutions and preventive measures will conclude my presentation.
3:00 PM
Scandium-containing Filler Material for Welding Aircraft Castings Made of High-temperature Magnesium-based Alloy: Vadim Shalomeev1; Sergei Sheyko2; Ievgeniia Chetvertak1; 1National University "Zaporizhska Politecnics"; 2Zaporizhzhia National University
Based on the results of the systematic research of structure and multi-component phases, formation filler material which contains scandium for aviation casting welding from the alloy of the system Mg-Zr-Nd was developed. Scandium influence in the filler magnesium alloy on its mechanical and special properties was studied. It was found that modifying of magnesium alloy by scandium in a quantity up to 0,05…0,07 % allows to get a fine-grained structure, increased level of mechanical properties and heat-resistance through complex intermetallic phases and hard solution microalloying formation. Aviation cast details welding produced from magnesium alloy by filler material which contains scandium allows to get a welding seam with a dense homogeneous fusion and around-seam zones without any defects. Applying of the filler material which contains scandium for welding products from the alloy of the system Mg-Zr-Nd allows increasing significantly mechanical properties, heat-resistance and reliability of aviation constructions as a whole.