TY - GEN
T1 - Oxidation behavior and pack siliconized oxidation-resistant coatings of an Nb-based ultrahigh temperature alloy
AU - Guo, X. P.
AU - Zhao, L. X.
AU - Guan, P.
AU - Kusabiraki, K.
PY - 2007
Y1 - 2007
N2 - The halide-activated pack cementation method was utilized to deposit suicide coatings on a multicomponent Nb-Ti-Si based alloy. The siliconized temperature was 1150°C and the holding time was 1Oh. Both the specimens with siliconized coatings and without coatings were oxidized at 1250°C for 5, 10, 20, 50 and 10h respectively. The coating possessed a double layer structure with the composition of (Nb,X)Si2 (X represents Ti, Cr and Hf), and the outer layer was denser. The major structure in the outer layer was composed of columnar crystals perpendicular to the interface between the coating and the substrate, and that in the inner layer was mainly composed of equiaxed crystals. A transitional layer about 5 μm thick was found between the coating and the substrate. After oxidation at 12500C, the major constituents in the scale were SiO2 and TiO2 and the mole ratio of these two phases was about 2:1. The thickness of the (Nb,X)Si2 layer decreased and that of transitional layer increased as the oxidation time prolonged. The siliconized coating exhibited excellent oxidation-resistance at 125°C within 50 hours.
AB - The halide-activated pack cementation method was utilized to deposit suicide coatings on a multicomponent Nb-Ti-Si based alloy. The siliconized temperature was 1150°C and the holding time was 1Oh. Both the specimens with siliconized coatings and without coatings were oxidized at 1250°C for 5, 10, 20, 50 and 10h respectively. The coating possessed a double layer structure with the composition of (Nb,X)Si2 (X represents Ti, Cr and Hf), and the outer layer was denser. The major structure in the outer layer was composed of columnar crystals perpendicular to the interface between the coating and the substrate, and that in the inner layer was mainly composed of equiaxed crystals. A transitional layer about 5 μm thick was found between the coating and the substrate. After oxidation at 12500C, the major constituents in the scale were SiO2 and TiO2 and the mole ratio of these two phases was about 2:1. The thickness of the (Nb,X)Si2 layer decreased and that of transitional layer increased as the oxidation time prolonged. The siliconized coating exhibited excellent oxidation-resistance at 125°C within 50 hours.
KW - Nb-Ti-Si based alloy
KW - Oxidation-resistance
KW - Scale
KW - Siliconized coating
UR - http://www.scopus.com/inward/record.url?scp=38349087030&partnerID=8YFLogxK
U2 - 10.4028/0-87849-462-6.371
DO - 10.4028/0-87849-462-6.371
M3 - 会议稿件
AN - SCOPUS:38349087030
SN - 0878494626
SN - 9780878494620
T3 - Materials Science Forum
SP - 371
EP - 374
BT - Selected, peer reviewed papers from The Sixth Pacific Rim International Conference on Advanced Materials and Processing, PRICM 6
PB - Trans Tech Publications Ltd
T2 - 6th Pacific Rim International Conference on Advanced Materials and Processing, PRICM 6
Y2 - 5 November 2007 through 9 November 2007
ER -
