TY - JOUR
T1 - Effects of processing parameters on alumina coatings deposited on nickel substrates by reacting aluminum chloride and hydrogen/carbon dioxide gas mixtures
AU - Bae, Yong W.
AU - Lee, Woo Y.
AU - Besmann, Theodore M.
AU - Cavin, O. Burl
AU - Watkins, Thomas R.
PY - 1998/7
Y1 - 1998/7
N2 - Pure nickel coupons were used as substrates in the deposition of alumina (Al2O3) from the reaction of aluminum chloride (AlCl3) with hydrogen/carbon dioxide gas mixtures in the temperature range of 954°-1100°C and system pressures of 2.7-13.3 kPa. The apparent activation energy estimated from the coating growth rate averaged 320 kJ/ mol at 13.3 kPa. At temperatures <1000°C, transition θ, κ, and δ modifications were codeposited with α-Al2O3, whereas single-phase α-Al2O3 was deposited at higher temperatures. At high AlCl3 partial pressures, nickel aluminide phases were sometimes codeposited with Al2O3, which was attributed to the reaction of AlCl3 with the nickel substrate in the presence of hydrogen gas.
AB - Pure nickel coupons were used as substrates in the deposition of alumina (Al2O3) from the reaction of aluminum chloride (AlCl3) with hydrogen/carbon dioxide gas mixtures in the temperature range of 954°-1100°C and system pressures of 2.7-13.3 kPa. The apparent activation energy estimated from the coating growth rate averaged 320 kJ/ mol at 13.3 kPa. At temperatures <1000°C, transition θ, κ, and δ modifications were codeposited with α-Al2O3, whereas single-phase α-Al2O3 was deposited at higher temperatures. At high AlCl3 partial pressures, nickel aluminide phases were sometimes codeposited with Al2O3, which was attributed to the reaction of AlCl3 with the nickel substrate in the presence of hydrogen gas.
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U2 - 10.1111/j.1151-2916.1998.tb02572.x
DO - 10.1111/j.1151-2916.1998.tb02572.x
M3 - Article
AN - SCOPUS:0032116377
SN - 0002-7820
VL - 81
SP - 1945
EP - 1948
JO - Journal of the American Ceramic Society
JF - Journal of the American Ceramic Society
IS - 7
ER -