사용된 IN738LC 가스 터빈 블레이드 코팅층의 고온 부식 및 Thermally Grown Oxide 형성 거동

최병학; 한성희; 김대현; 안종기; 이재현; 최광수; Byung Hak Choe; Sung Hee Han; Dae Hyun Kim; Jong Kee Ahn; Jae Hyun Lee; Kwang Su Choi

Korean Journal of Materials Research, Vol.32, No.4, 200-209, April, 2022

DOI10.3740/MRSK.2022.32.4.200 Export Citation

사용된 IN738LC 가스 터빈 블레이드 코팅층의 고온 부식 및 Thermally Grown Oxide 형성 거동

Hot Corrosion and Thermally Grown Oxide Formation on the Coating of Used IN738LC Gas Turbine Blade

최병학^†, 한성희, 김대현, 안종기¹, 이재현 ², 최광수³

강릉원주대학교 신소재금속공학과
¹한화에어로스페이스
²창원대학교 신소재공학부
³국립과학수사연구원 법공학부 안전과

Byung Hak Choe^†, Sung Hee Han, Dae Hyun Kim, Jong Kee Ahn¹, Jae Hyun Lee², and Kwang Su Choi³

Department of Metal and Materials Engineering, Gangneung-Wonju National University, Gangneung 25457, Republic of Korea
¹Hanwha Aerospace, Sungnam 13488, Republic of Korea
²School of Material Science & Engineering, Changwon National Univ., Changwon, Changwon 51140, Republic of Korea
³Forensic Safety Division, National Forensic Service, Wonju 26460, Republic of Korea

E-mail:

In this study, defects generated in the YSZ coating layer of the IN738LC turbine blade are investigated using an optical microscope and SEM/EDS. The blade YSZ coating layer is composed of a Y-Zr component top coat layer and a Co component bond coat layer. A large amount of Cr/Ni component that diffused from the base is also measured in the bond coat. The blade hot corrosion is concentrated on the surface of the concave part, accompanied by separation of the coating layer due to the concentration of combustion gas collisions here. In the top coating layer of the blade, cracks occur in the vertical and horizontal directions, along with pits in the top coating layer. Combustion gas components such as Na and S are contained inside the pits and cracks, so it is considered that the pits/cracks are caused by the corrosion of the combustion gases. Also, a thermally grown oxide (TGO) layer of several μm thick composed of Al oxide is observed between the top coat and the bond coat, and a similar inner TGO with a thickness of several μm is also observed between the bond coat and the matrix. A PFZ (precipitate free zone) deficient in γ' (Ni3Al) forms as a band around the TGO, in which the Al component is integrated. Although TGO can resist high temperature corrosion of the top coat, it should also be considered that if its shape is irregular and contains pore defects, it may degrade the blade high temperature creep properties. Compositional and microstructural analysis results for hightemperature corrosion and TGO defects in the blade coating layer used at high temperatures are expected to be applied to sound YSZ coating and blade design technology.

Keywords:IN738LC superalloy;gas turbine blade;YSZ coating;hot corrosion;thermally grown oxide

[References]

Bannazadeh R, Riahi M, Aieneravaie M, Amirkabir J. Mech. Eng., 50, 35 (2018)
Rani S, Agrawal AK, Rastogi V, Case Stud. Eng. Failure Anal., 8, 1 (2017)
Mazur Z, Luna-Ramírez A, Juárez-Islas JA, Campos-Amezcua A, Eng. Fail. Anal., 12, 474 (2005)
Yoo KB, Lee HS, Yoon YK, Kim JH, Procedia Eng., 10, 2490 (2011)
Clarke DR, Oechsner M, Padture NP, MRS Bulletin, 37, 891 (2012)
Sampath S, Schulz U, Jarligo MO, Kuroda S, MRS Bulletin, 37, 903 (2012)
Ghasemi R, Vakilifard H, Ceram. Int., 43, 8556 (2017)
Chen WR, Archer R, Huang X, Marple BR, J. Therm. Spray Technol., 17, 858 (2008)
Kim HJ, Kim MT, Park HW, J. Korean Inst. Surf. Eng., 45, 70 (2012)
Rabiei A, Evans AG, Acta Mater., 48, 3963 (2000)
Jiang P, Fan X, Sun Y, Li D, Li B, Wang T, Mater. Des., 132, 559 (2017)
El-Awadi GA, Abdel-Samad S, Elshazly ES, Appl. Surf. Sci., 378, 224 (2016)
Eliaz N, Shemesh G, Latanision RM, Eng. Fail. Anal., 9, 31 (2002)
Prashar G, Vasudev H, Mater. Today. Proc., 26, 1131 (2016)
Gurrappa I, Oxid. Met., 51, 353 (1999)
Kamal S, Sharma KV, Abdul-Rani AM, J. Miner. Mater. Char. Eng., 3, 26 (2015)
Nicholls MR, Simms NJ, Chan WY, Evans HE, Surf. Coat. Technol., 149, 236 (2002)
Lee DB, Sci. Adv. Mater., 7, 1464 (2015)
Potgieter JH, Maledi NB, Sephton M, Cornish LA, Platinum Met. Rev., 54, 112 (2010)
Nakagawa Y, Superalloys, p.3, ed. Green KA, Pollock TM, Harada H, TMS (The Minerals, Metals & Materials Society), (2004).
Okada I, Torigoe T, Takahashi K, Izutsu D, Superalloys, p.707, ed. Green KA, Pollock TM, Harada H, TMS (The Minerals, Metals & Materials Society), (2004).
Srinivasa KS, Rani SD, Int. J. Appl. Res. Mechanical Eng., 3, 2231 (2013)

[Related Articles]

[1] Bannazadeh R, Riahi M, Aieneravaie M, Amirkabir J. Mech. Eng., 50, 35 (2018)

[2] Rani S, Agrawal AK, Rastogi V, Case Stud. Eng. Failure Anal., 8, 1 (2017)

[3] Mazur Z, Luna-Ramírez A, Juárez-Islas JA, Campos-Amezcua A, Eng. Fail. Anal., 12, 474 (2005)

[4] Yoo KB, Lee HS, Yoon YK, Kim JH, Procedia Eng., 10, 2490 (2011)

[5] Clarke DR, Oechsner M, Padture NP, MRS Bulletin, 37, 891 (2012)

[6] Sampath S, Schulz U, Jarligo MO, Kuroda S, MRS Bulletin, 37, 903 (2012)

[7] Ghasemi R, Vakilifard H, Ceram. Int., 43, 8556 (2017)

[8] Chen WR, Archer R, Huang X, Marple BR, J. Therm. Spray Technol., 17, 858 (2008)

[9] Kim HJ, Kim MT, Park HW, J. Korean Inst. Surf. Eng., 45, 70 (2012)

[10] Rabiei A, Evans AG, Acta Mater., 48, 3963 (2000)

[11] Jiang P, Fan X, Sun Y, Li D, Li B, Wang T, Mater. Des., 132, 559 (2017)

[12] El-Awadi GA, Abdel-Samad S, Elshazly ES, Appl. Surf. Sci., 378, 224 (2016)

[13] Eliaz N, Shemesh G, Latanision RM, Eng. Fail. Anal., 9, 31 (2002)

[14] Prashar G, Vasudev H, Mater. Today. Proc., 26, 1131 (2016)

[15] Gurrappa I, Oxid. Met., 51, 353 (1999)

[16] Kamal S, Sharma KV, Abdul-Rani AM, J. Miner. Mater. Char. Eng., 3, 26 (2015)

[17] Nicholls MR, Simms NJ, Chan WY, Evans HE, Surf. Coat. Technol., 149, 236 (2002)

[18] Lee DB, Sci. Adv. Mater., 7, 1464 (2015)

[19] Potgieter JH, Maledi NB, Sephton M, Cornish LA, Platinum Met. Rev., 54, 112 (2010)

[20] Nakagawa Y, Superalloys, p.3, ed. Green KA, Pollock TM, Harada H, TMS (The Minerals, Metals & Materials Society), (2004).

[21] Okada I, Torigoe T, Takahashi K, Izutsu D, Superalloys, p.707, ed. Green KA, Pollock TM, Harada H, TMS (The Minerals, Metals & Materials Society), (2004).

[22] Srinivasa KS, Rani SD, Int. J. Appl. Res. Mechanical Eng., 3, 2231 (2013)