TY - JOUR
T1 - Characteristics and thermal cycling behavior of plasma-sprayed Ba(Mg1/3Ta2/3)O3 thermal barrier coatings
AU - Cao, Yupeng
AU - Wang, Quansheng
AU - Liu, Yanbo
AU - Ning, Xianjin
AU - Wang, Hao
N1 - Publisher Copyright:
© 2017 Elsevier Ltd and Techna Group S.r.l.
PY - 2017/10/1
Y1 - 2017/10/1
N2 - Ba(Mg1/3Ta2/3)O3 (BMT) powders were synthesized by the solid state reaction method. BMT thermal barrier coatings (TBCs) were deposited by atmospheric plasma spraying (APS). The phase composition and microstructure of the BMT coatings were characterized. The thermal cycling behavior of the BMT coatings was investigated by the water quenching method from 1150 °C to room temperature. The results reveal that BMT powders have an ordered hexagonal perovskite structure, whereas the as-sprayed coating of BMT has a disordered cubic perovskite structure because of the different degree of structural order for different treatment conditions. During thermal cycling testing, the entire spalling of coatings occurred within the BMT coating near the bond coat. This is attributed to the following reasons: (1) the growth of a thermally grown oxides (TGO) layer, which leads to additional stresses in the coatings; (2) the coefficient of thermal expansion mismatch between the BMT coating and bond coat, which develops enormous stress in the coatings; (3) the precipitation of Ba3Ta5O15 due to the evaporation of MgO during the spraying process, which changes the continuity of the coatings.
AB - Ba(Mg1/3Ta2/3)O3 (BMT) powders were synthesized by the solid state reaction method. BMT thermal barrier coatings (TBCs) were deposited by atmospheric plasma spraying (APS). The phase composition and microstructure of the BMT coatings were characterized. The thermal cycling behavior of the BMT coatings was investigated by the water quenching method from 1150 °C to room temperature. The results reveal that BMT powders have an ordered hexagonal perovskite structure, whereas the as-sprayed coating of BMT has a disordered cubic perovskite structure because of the different degree of structural order for different treatment conditions. During thermal cycling testing, the entire spalling of coatings occurred within the BMT coating near the bond coat. This is attributed to the following reasons: (1) the growth of a thermally grown oxides (TGO) layer, which leads to additional stresses in the coatings; (2) the coefficient of thermal expansion mismatch between the BMT coating and bond coat, which develops enormous stress in the coatings; (3) the precipitation of Ba3Ta5O15 due to the evaporation of MgO during the spraying process, which changes the continuity of the coatings.
KW - Atmospheric plasma spraying
KW - Perovskite structure
KW - Thermal barrier coatings
KW - Thermal cycling behavior
UR - http://www.scopus.com/inward/record.url?scp=85019722497&partnerID=8YFLogxK
U2 - 10.1016/j.ceramint.2017.05.134
DO - 10.1016/j.ceramint.2017.05.134
M3 - Article
AN - SCOPUS:85019722497
SN - 0272-8842
VL - 43
SP - 10955
EP - 10959
JO - Ceramics International
JF - Ceramics International
IS - 14
ER -