TY - JOUR
T1 - Self-healing performance of niobium suboxide-based solid solution for UHTC coating during oxyacetylene test
AU - He, Ruixiang
AU - Li, Kezhi
AU - Liu, Qian
N1 - Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/7/15
Y1 - 2021/7/15
N2 - In this work, NbC coatings modified with different contents (0, 25 and 50 mol%) of HfC were deposited on SiC-coated C/C composites via supersonic atmospheric plasma spraying to study the effect of HfC on the ablation-resistance of the NbC coatings under an oxyacetylene torch. The phase composition and chemical states of Nb2O5–66.67 mol% HfO2 plates heated up to 2100 °C in an Ar atmosphere were investigated. The results confirmed that the effective ablation time of the NbC-coating mixed with 50 mol% HfC was approximately 120 s, which is more than twice that of the pure NbC coating. During air quenching, NbO and NbO2 ultimately transformed into Nb2O5, producing compressive stress that stabilized the t-HfO2 crystals. Furthermore, the formation of hafnium oxide significantly improved the thermal stability and viscosity of the Nb–O film, and the niobium suboxide-based solid solution, possessing an attractive self-healing performance, increased the compactness of the HfO2-based solid solution layer are responsible for the superior ablation performance of the NbC-HfC coating.
AB - In this work, NbC coatings modified with different contents (0, 25 and 50 mol%) of HfC were deposited on SiC-coated C/C composites via supersonic atmospheric plasma spraying to study the effect of HfC on the ablation-resistance of the NbC coatings under an oxyacetylene torch. The phase composition and chemical states of Nb2O5–66.67 mol% HfO2 plates heated up to 2100 °C in an Ar atmosphere were investigated. The results confirmed that the effective ablation time of the NbC-coating mixed with 50 mol% HfC was approximately 120 s, which is more than twice that of the pure NbC coating. During air quenching, NbO and NbO2 ultimately transformed into Nb2O5, producing compressive stress that stabilized the t-HfO2 crystals. Furthermore, the formation of hafnium oxide significantly improved the thermal stability and viscosity of the Nb–O film, and the niobium suboxide-based solid solution, possessing an attractive self-healing performance, increased the compactness of the HfO2-based solid solution layer are responsible for the superior ablation performance of the NbC-HfC coating.
KW - Ablation-resistance
KW - Carbon/carbon composites
KW - NbC-HfC coating
KW - Niobium suboxide-based solid solution
KW - Self-healing performance
KW - Supersonic atmospheric plasma spraying
UR - http://www.scopus.com/inward/record.url?scp=85104780891&partnerID=8YFLogxK
U2 - 10.1016/j.surfcoat.2021.127190
DO - 10.1016/j.surfcoat.2021.127190
M3 - 文章
AN - SCOPUS:85104780891
SN - 0257-8972
VL - 417
JO - Surface and Coatings Technology
JF - Surface and Coatings Technology
M1 - 127190
ER -