TY - JOUR
T1 - Experimental investigations and thermodynamic calculations of the interface reactions between ceramic moulds and Ni-based single-crystal superalloys: Role of solubility of Y in the LaAlO3 phase
AU - Wang, Hang
AU - Shang, Genfeng
AU - Liao, Jinfa
AU - Yang, Bin
AU - Yuan, Chen
PY - 2018/5/1
Y1 - 2018/5/1
N2 - It is commonly recognised that more reactive elements contained in Ni-based superalloy result in more-severe interfacial reactions, and thus more inclusions formed at the interface. However, the present work revealed that with rare-earth elements, specifically 0.24 wt.% La+Y added to Ni-based superalloys, the interfacial reaction (~5 µm in thickness) between the ceramics and metal was retarded compared to the case of 0.12 wt.% Y (~10 µm in thickness). Scanning electron microscopy, focused ion-beam transmission electron microscopy, and X-ray photoelectron spectroscopywere used to characterise the microstructure at the interface. Thermodynamic calculations of the Gibbs free energies of interfacial reactions were conducted. Experimental and theoretical results show that the solubility of Y in the LaAlO3 phase (>3.4 at.%) hinders interfacial reactions
AB - It is commonly recognised that more reactive elements contained in Ni-based superalloy result in more-severe interfacial reactions, and thus more inclusions formed at the interface. However, the present work revealed that with rare-earth elements, specifically 0.24 wt.% La+Y added to Ni-based superalloys, the interfacial reaction (~5 µm in thickness) between the ceramics and metal was retarded compared to the case of 0.12 wt.% Y (~10 µm in thickness). Scanning electron microscopy, focused ion-beam transmission electron microscopy, and X-ray photoelectron spectroscopywere used to characterise the microstructure at the interface. Thermodynamic calculations of the Gibbs free energies of interfacial reactions were conducted. Experimental and theoretical results show that the solubility of Y in the LaAlO3 phase (>3.4 at.%) hinders interfacial reactions
KW - ceramic mould
KW - Ni-based superalloys
KW - interfacial reaction
KW - rare-earth elements
KW - thermodynamic calculations
U2 - 10.1016/j.ceramint.2018.01.192
DO - 10.1016/j.ceramint.2018.01.192
M3 - Article
SN - 0272-8842
VL - 44
SP - 7667
EP - 7673
JO - Ceramics International
JF - Ceramics International
IS - 7
ER -