Thermal stability and oxidation resistance of TiCrAlYO coatings on SS430 for solid oxide fuel cell interconnect applications

Oxidation Resistant, Cr Retaining, Electrically Conductive Coatings on Metallic Alloys for SOFC Interconnects

“…The uncoated FSS continues to volatilize Cr throughout the test, while the coated specimen demonstrates negligible Cr volatility after the first 24 hours. This coating contains ~12at% Cr; however, the Cr is apparently sequestered in a solid solution with complex Al-containing oxides, which agrees well with thermochemical modeling [26].…”

“…This phenomenon has been attributed to coating evolution, e.g., recrystallization, and outward transport of Mn from the steel through the coating, and was discussed in previous reports and in published literature. The lowest ASR values are realized with the Mn-containing coating, e.g., "TiMnCoCrAlYO", which also demonstrates excellent thermal stability [26]. Figure 17 presents cross-sectional SEM images of coated and uncoated 430 SS after 1,500 hours of ASR testing with LSM contact.…”

Effect of Cr2O3 on the 18O tracer incorporation in SOFC materials

“…The exact process of the deposition is still controversial, as pointed out by Jiang and Zhen [9]. Mitigation strategies are being explored, mainly by application of protective interconnect coatings [12]. Still, the controversy remains as to whether the Cr 2 O 3 deposition is electrochemical in nature [11,13] or if it is a nucleation-governed reaction [9,14].…”

Evaluation of SOFC Interconnects Made of Ferritic Steels with Nano-Structured Oxi-Ceramic Protective Coatings Deposited by the LAFAD Process

“…The lowest ASR values are realized with the (Co,Mn)-containing coating, e.g., "CoMnTiCrAlYO", which also demonstrates excellent thermal stability. 32 Figure 2 presents cross-sectional SEM images of coated and uncoated 430 SS coupons after 1,500 h of ASR testing with LSM contact. All of the coatings have retained their as-deposited $2 lm thickness through the 1500 h ASR test, with some exhibiting compositional stratification (Mn-rich surface crystallites above amorphous alumina base-layer).…”

“…It was found that some coatings retained their as-deposited amorphous structure after more than 1,500 h exposure in 800 C air, which demonstrates the high thermal-chemical stability of this coating design during high temperature exposure. 32 Characterization of nanocomposite monolithic LAFAD coatings.-A second iteration of LAFAD process runs were performed by using targets having either identical or different multielemental composition. In these processes, the dividing baffle was removed allowing a free mixing of two opposite vapor plasma flows in the plasma guide chamber.…”