Abstract
The effect of dopant species on the sintering resistance of zirconia-based ceramics remains a huge challenge in terms of both experiment and theory. As one of the most popular materials for high-temperature protective coatings, it is still urgent to obtain rare earth-doped ZrO2 with high sintering resistance and good phase stability. Here, the sintering resistance and phase stability of rare earth oxides (La2O3, Nd2O3, Gd2O3, and Y2O3)-stabilized zirconia (ZrO2) were thoroughly studied by theoretical and experimental methods. According to experimental data, ZrO2 doped with rare earth ions with larger radii (La3+, Nd3+, and Gd3+) exhibited improved sintering resistance at reduced tetragonal phase stability. Molecular dynamics simulation results revealed that rare earth ions with larger ionic radii are prone to segregation at grain boundaries, which can more effectively reduce the grain boundary energy in the materials under consideration. Therefore, the proposed approach involving doping of NdO1.5 (~1 mol%) and YO1.5 (YbO1.5, 6 mol%) in ZrO2 is considered to be a promising route for the effective preparation of sinter-resistant ZrO2-based ceramics for refractory and thermal barrier materials.
Highlights
Thermal barrier coatings (TBCs) are advanced coatings applied on metallic surfaces in exhaust heat management systems such as gas turbines or aero-engine parts, which are continuously exposed to high temperatures [1,2,3,4]
The sintering behavior and phase stability of tetragonal ZrO2 doped with rare earth elements with large ionic radii were thoroughly investigated, and the key results of this study are as follows: 5. Conclusions
The sintering behavior and phase stability of tetragonal ZrO2 doped with rare earth elements with large ionic radii were thoroughly investigated, and the key results of this study are as follows: 1
Summary
Thermal barrier coatings (TBCs) are advanced coatings applied on metallic surfaces in exhaust heat management systems such as gas turbines or aero-engine parts, which are continuously exposed to high temperatures [1,2,3,4]. Systematically investigated the sintering processes of YSZ TBCs, discovering that the closure of two-dimensional (2D) pores noticeably increased the thermal conductivity by nearly 50% after 20 h of calcination at 1200 ◦ C and reduced the mechanical properties of the corresponding coatings. Their elastic moduli increased drastically from 70 to 150 GPa, reducing the thermal shock resistance and even leading to premature shedding of the coatings [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
