TY - JOUR
T1 - Control of bond coat microstructure in HVOF process for thermal barrier coatings
AU - Myoung, Sang Won
AU - Lu, Zhe
AU - Jung, Yeon Gil
AU - Jang, Byung Koog
AU - Paik, Ungyu
N1 - Funding Information:
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) ( 2011-0030058 ) and the Power Generation & Electricity Delivery ( 2011T100200224 ) of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Trade, Industry and Energy .
PY - 2014/12/15
Y1 - 2014/12/15
N2 - The microstructure of bond coat was optimized by controlling coating parameters, such as spray distances, the gas flow ratio of air/oxygen/hydrogen, gun speed, and step distance, in high-velocity oxy-fuel process, and the effects of coating parameters on the microstructure and thermomechanical properties were investigated. When the spray distance to the substrate shortened, the microstructure became dense and the hardness values were increased. As the amount of hydrogen increased in the fixed gas flow ratio, defects such as global pores and oxides were increased and the hardness values were decreased, showing a similar trend in oxygen. The bond coat with the step distance of 8. mm showed a slightly higher hardness value than that with the step distance of 5. mm, indicating that the gun speed did not have much effect on the hardness value. However, in thermal diffusivity, the bond coat with the step distance of 5. mm showed lower values than that with the step distance of 8. mm. The optimum coating parameters could be proposed in HVOF process.
AB - The microstructure of bond coat was optimized by controlling coating parameters, such as spray distances, the gas flow ratio of air/oxygen/hydrogen, gun speed, and step distance, in high-velocity oxy-fuel process, and the effects of coating parameters on the microstructure and thermomechanical properties were investigated. When the spray distance to the substrate shortened, the microstructure became dense and the hardness values were increased. As the amount of hydrogen increased in the fixed gas flow ratio, defects such as global pores and oxides were increased and the hardness values were decreased, showing a similar trend in oxygen. The bond coat with the step distance of 8. mm showed a slightly higher hardness value than that with the step distance of 5. mm, indicating that the gun speed did not have much effect on the hardness value. However, in thermal diffusivity, the bond coat with the step distance of 5. mm showed lower values than that with the step distance of 8. mm. The optimum coating parameters could be proposed in HVOF process.
UR - http://www.scopus.com/inward/record.url?scp=84918836995&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84918836995&partnerID=8YFLogxK
U2 - 10.1016/j.surfcoat.2014.08.081
DO - 10.1016/j.surfcoat.2014.08.081
M3 - Article
AN - SCOPUS:84918836995
SN - 0257-8972
VL - 260
SP - 63
EP - 67
JO - Surface and Coatings Technology
JF - Surface and Coatings Technology
ER -