Advanced Materials for Harsh Environments: Session I
Program Organizers: Navin Manjooran, Solve Technology and Research, Inc.; Gary Pickrell, Virginia Tech

Monday 8:00 AM
September 30, 2019
Room: C126
Location: Oregon Convention Center

Session Chair: Gary Pickrell, Virginia Tech; Navin Manjooran, Solve

8:00 AM  Keynote
Materials Under Extreme Environments at the Atomic Scale: Susan Sinnott1; 1Pennsylvania State University
    The behavior of materials under extreme environments is of interest to numerous applications and is particularly well suited to investigation with computational methods. One such application is that of nuclear materials, including nuclear fuels undergoing fission and cladding that is exposed to heat and highly reactive environments. This presentation will discuss the responses of these materials to these environments at the atomic scale. The approaches used are electronic structure calculations and classical atomistic simulations with reactive force fields. The insights gained provide insight into the macroscale responses of these technologically important systems.

8:40 AM  Invited
Alloy Design and Process Development for Direct Shape Forming of Fe-based ODS Alloys with Oxidation Resistance by Cold Spray Deposition: Iver Anderson1; Rebecca Whitesell1; Emma White1; Timothy Prost1; Stuart Maloy2; Timothy Eden3; Todd Palmer3; 1Iowa State University / Ames Laboratory; 2Los Alamos National Laboratory; 3Pennsylvania State University
    Ni-base superalloys may be replaced by oxide dispersion strengthened (ODS) ferritic stainless steels with Al-oxide scale forming capability for high-efficiency fossil-fueled power plants due to their stable (up to 1,000 ̊C) nano-oxide dispersoids. Accident tolerant fuel cladding for nuclear power plants may also adopt Al-containing ODS alloys, substituting for Zircaloy. Unfortunately, industrial processing of ODS ferritic alloys is complex/expensive due to mechanical alloying (for days) of alloy powders with Y2O3 particulate and extensive hot deformation processing of mill shapes with high strength and limited ductility. Experimental cold spray of precursor gas atomized powders can deposit heavily work-hardened final shapes with promotion of enhanced dispersoid strengthening. Results of the streamlined cold spray approach for producing ODS alloys from as-atomized GARS (gas atomization reaction synthesis) alloy powders will be reported as a function of heat treatment and final consolidation processing. Support from DOE-FE and NE through Ames Lab contract No. DE-AC02-07CH11358.

9:00 AM  
Alloy Coatings by Electrodeposition for Improved Corrosion Resistance: Timothy Hall1; Jing Xu1; Santosh Vijapur1; Jennings Taylor1; Maria Inman1; Rajeswaran Radhakrishnan1; Stephen Snyder1; 1Faraday Technology, Inc.
    This presentation will discuss the potential to electrodeposit alloy coating onto various substrates and improve the corrosion resistance within harsh environments. Specifically, we will discuss the potential to electrodeposit gradient, composite, and ternary alloy systems of NiMo, NiCoCrAlY, and NiCoCr as well as others. Then we will explore their potential to improve the lifetime and durability of materials within high temperature and salted environments. Finally, we will explore the challenges of applying these coatings to complex system components like turbines, molten salt reactor, and bio-combustors.

9:20 AM  
Adsorption and Corrosion Inhibition Effect of Ammonium Molybdate Tetrahydrate on Mild Steel in 1M of HCl: Ojo Sunday Fayomi1; 1Covenant University
    The inhibition of mild steel varying concentration of ammonium molybdate tetrahydrate (AMT) in 1M HCl has been studied using linear potentiodynamic polarization (LPP) techniques. SEM was used to examine the morphology of the samples, while the microhardness of the test samples were investigated using the Vickers hardness testing techniques. The outcome of the linear polarization test unveils decrease in the rate of corrosion with the increase in the mass concentration of ammonium molybdate tetrahydrate in the corrosive environment. The inhibited samples were found to exhibit reduced current density and higher value of polarization resistance compared to the uninhibited sample. The SEM micrograph shows that the inhibited samples exhibits better morphology compared to the bared sample with notable thin inhibitory layer. The examination of the microhardness of the samples shows that the inhibited samples displayed improved percentage in microhardness.

9:40 AM  
Corrosion Assessment and Materials Selection for The Construction of Flue Gas Core Components at Advanced Pressurized Oxy-fuel Combustion Plants: Yimin Zeng1; Kaiyang Li2; Jing-li Luo2; 1NRCan, Canada; 2University of Alberta
    Pressurized oxy-fuel combustion is an advanced power/heat generation technology in which pure O2 instead of air supports pressurized combustion for the significant reduction of CO2 emission and remarkable improvement of energy conversion efficiency. The flue gas-induced corrosion poses a challenge on materials selection. The specific chemistry and operating pressure of flue gas result in different hot gas and condensed phase corrosion. Based on lab researches and field experience in conventional air-fuel power plants, several candidate alloys have been recommended for the construction of flue gas core components, including austenitic stainless steels, duplex stainless steels and Ni-based alloys. However, their performance is still unclear. In this paper, standard immersion tests and in-situ electrochemical tests at elevated temperatures were conducted to evaluate the corrosion behavior of candidate alloys under simulated flue gas operating conditions. Microscopy was also applied to examine the formed corrosion products for the fundamental understanding of corrosion process.

10:00 AM Break

10:20 AM  
Development of a Diamond Containing Material for Drilling in UltraHard Formations: Jianhui Xu1; Weicheng Li2; Xu Wang1; Jianlin Yao2; Chris Cheng1; Yonghong Wang1; Xiongwen Yang1; 1CNPC USA, CNPC; 2Chuanqing Drilling Engineering Company, CNPC
    The exploration and exploitation of oil and gas resources in deeper wells present a significant challenge to the drilling technology due to high hardness and abrasiveness of the formation. Impregnated diamond material with its supreme strength has been playing a key role in combating the aforementioned challenging application. In this study, we demonstrated the development of a key component – the impregnated segment, of this technology. A design of experiment encompassing various key parameters, such as diamond concentration, tungsten carbide and metal binder was conducted to optimize the recipe. The ASTM B611 wear test was performed to benchmark the material performance against baseline products. It showed that one recipe successfully achieved 19% improvement when compared with the baseline material. The microstructural response in material was also discussed in this paper. The material has been integrated in the impregnated bit design and ready for field test in drilling ultra-hard formation.

10:40 AM  
High Temperature Corrosion of Iron Alloys for Direct Fired sCO2 Power Cycle Applications: Joseph Tylczak1; Gordon Holcomb1; Richard Oleksak2; Ímer Doğan1; 1National Energy Technology Laboratory; 2National Energy Technology Laboratory, Leidos Rsearch Support Team
    Several emerging power cycles uses supercritical CO2 (sCO2) for the working fluid. Alloys used to contain sCO2 in a direct sCO2 power cycle will also be exposed to water due to combustion, residual O2, and possibly some sulfur compounds. This work looks at corrosion resistance of Fe based alloys in simulated direct fired exposure conditions at various elevated temperatures. The exposures were done in 95 vol % CO2, 4 % water, 1 % O2, with and without 0.1 % SO2 at temperatures from 550 to 650 ░C in 500 h cycles to a total of 3000 h. Alloys included medium (9-16 wt %) Cr and high (17-26 wt %) Cr variants. Relative to the 9 Cr alloys, those with at least 12 wt % Cr had significantly lower mass gains in the environments without SO2. Additions of SO2 increased the corrosion rate for most of the alloys.

11:00 AM  
Corrosion Behavior of Iron and Nickel Based Alloys in Superheater Tube Environments: Kasey Hanson1; Preet Singh1; 1Georgia Tech
    Recovery boilers are used in the pulp and paper industry, in part, to recover pulping chemicals for future reuse and to recover energy by producing steam. Operating temperatures of recovery boiler are generally kept below or near 500░C, however increasing their operating temperature is limited due to the failure of its superheater tubes through accelerated corrosion. These superheater tubes are exposed to gaseous environments containing sulfur-bearing gases and water vapor, in addition to molten salt deposits (sulfates, carbonates, chlorides), at the tube surface, whose compositions can vary. The main aim of this study is to assess the performance of selected iron and nickel based alloys in each corrosive component individually, as well as studying the combined effect of salt deposits and gaseous environments on corrosion rates and mechanisms. This talk will present reaction kinetics, characterization of corrosion products, and propose corrosion mechanisms for different alloys in these harsh environments.

11:20 AM Concluding Comments