Advanced Materials for Harsh Environments: Session III
Sponsored by: ACerS Electronics Division
Program Organizers: Navin Manjooran, Solve; Gary Pickrell, Virginia Tech
Tuesday 8:00 AM
October 11, 2022
Room: 333
Location: David L. Lawrence Convention Center
Session Chair: Darren Pagan, Pennsylvania State University; Navin Manjooran, Chairman, Solve; Gary Pickrell, Virginia Tech
8:00 AM Invited
New Insights into High Temperature Interfacial Strain Mechanisms from High Temperature in Situ TEM: Shen Dillon1; 1University of California, Irvine
Strain and failure at interfaces often present a limitation to the performance of engineering systems and materials at high temperatures, including spalling failure and creep deformation. This talk discusses the development and application of ultrahigh temperature in situ transmission electron microscopy characterization based mechanical testing using localized laser heating. The approach is applied to characterizing interfacial strain at individual grain boundaries. Interestingly, bicrystal experiments suggest interfacial strain tends to be governed by nucleation rate limited kinetics, rather than diffusional kinetics, up to relatively large stresses in many materials, i.e. 100’s of MPa. These data are utilized to formulate a new model for grain boundary creep. The phenomenon is also observed at metal-oxide interfaces, and implications for environmental barrier coatings will be discussed.
8:40 AM
Root Cause Spectroscopic Failure Investigation Aided by High Resolution SEM/EDS, FT-IR, XPS Instruments: Jeanette Vass1; 1Auto and Materials
My talk will demonstrate the severe consequences of non-compliance with Quality-Control and Testing Protocols. This investigative study reveals a devastating failure affecting more than 100,000 newly built Southeastern US coastal homes where living conditions became dangerously toxic, resulting in a serious environmental catastrophe with an enormous cost of 2 billion dollars. Our laboratory team was forewarned and started investigating this this very alarming, widespread, environmentally induced disaster.My presentation describes how the investigation established and accurately identified the root causes through applied and integrated application of Standard and Micro-Scale-Spectroscopic Tools in failure analysis (FT-IR, SEM-EDS, XPS, & more). By identifying the emitted corrosive substance, our investigation determined the root cause of the problem and enabled area residents to secure compensation through Class-Action-Lawsuits. Lesson to be learned: the enormous health and reconstruction cost of this devastating failure could have been prevented and this presentation will show you how.
9:00 AM
Stress Corrosion Mitigation in Al-Mg via Zn-Rich Primers and Long-Term Performance Stability: Matthew McMahon1; Eric Dau1; Allison Akman1; Fatou Cisse1; 1Naval Surface Warfare Center, Carderock Division
The Al-Mg alloy AA5456 achieves a unique combination of weldability, general marine corrosion resistance, and high strength-to-weight ratio when utilized at relatively low temperatures in service. However, prolonged exposure to temperatures of at least 40ᵒC promotes Mg diffusion to the grain boundaries to form the highly anodic β phase in a process termed sensitization, which promotes stress corrosion cracking (SCC) and premature failure in seawater conditions. Previous work demonstrated that inorganic Zn-rich primers have a unique capability to provide stable, long-term cathodic protection that reduces the β phase corrosion rate and mitigates SCC in full immersion conditions. This work evaluates the maintenance of ZRP polarizability and cathodic protection performance over extended seawater and UV exposure, and quantifies the impact of primer degradation on the level of SCC mitigation achieved on highly sensitized AA5456. Testing is conducted in full immersion and alternate immersion conditions to more accurately simulate marine service conditions.
9:20 AM
Titanium Coatings on Materials for Harsh Environments and Corrosion in Interaction with the Environment in Coke Production: Borys Sereda1; Iryna Kruhliak1; Dmytro Sereda1; Dmytro Kruhliak1; 1Dneprovsky State Technical University
This paper examines the production of alloyed Titanium coatings on materials for harsh environments and corrosion in interaction with the environment in coke production. This article deals with the production of alloyed titanium coatings on materials for harsh operating conditions and corrosion in interaction with the environment in the coke production. This type of protection is the most promising and less costly. In this work, we obtained coatings under non-isothermal conditions. The composition of the saturating medium was determined by mathematical modeling of protective coatings on different materials. Comparative analysis of corrosion resistance of protective coatings showed an increase in corrosion resistance by 1.6-1.8 times, compared with the material treated in isothermal conditions when operating equipment in the conditions of coke-chemical production.
9:40 AM
Understanding Hydration-induced Cracking, Corrosion and Self-healing Mechanisms in Advanced Concrete Using Electron Microscopy and Quantitative Non-destructive 3D Mineral Characterization: Andy Holwell1; Maadhav Kothari1; Edward Hill1; Tanvir Qureshi1; 1Carl Zeiss Microscopy LLC
Almost all civil engineering infrastructure requires concrete. Cracks in concrete due to hydration, corrosion and chemical changes are a major source of reduced durability and financial loss. One such degradation mechanism is hydration-induced cracking that can result in devastating effects. Here we demonstrate hydration of self-healing concrete in situ within the chamber of a scanning electron microscope under variable pressure. Mechanistic effects of cracking and self-healing are studied via electron imaging and electron dispersive X-ray spectroscopy, to visualise the re-crystallisation of calcium carbonate in effectively healing the material.We further employ 3D X-ray microscopy alongside 3D mineralogy to determine structure and composition within a concrete core non-destructively, understanding particles, mineral relationships, and structure of concrete, even deeply buried features. We use a ground-breaking technique that can quantitatively assess mineral composition in a bulk using characteristic X-ray back projection energies and deep learning-based reconstruction of 3D X-ray data.
10:00 AM Concluding Comments