Simultaneous coating of Si and B on Nb–Si–B alloys by a halide activated pack cementation method and oxidation behaviors of the alloys with coatings at 1100 °C

Effects ofSiCandSiC-GNP additions on the mechanical properties and oxidation behavior of NbB2

“…Mansurova et al [41] studied the oxidation behavior of Nb-Si eutectic alloy and explained the formation of the Nb 3 BO 9 phase as a result of the interaction of B 2 O 3 and Nb 2 O 5 when the temperature is above 750°C. Similarly, Cheng et al [42] reported formation of the Nb 3 BO 9 phase in the form of 3Nb 2 O 5 .B 2 O 3 in Nb-B-Si alloys after oxidation at 1100°C for 1h and attributed the existence of this phase to the transformation of Figure 7 shows the cross-sectional morphology and EDS mapping of sample 30S after oxidation at 1200°C for 180 min. When the specimen was exposed to air at 1200°C,~245 µm thick continuous oxide layer was formed on the surface (Figure 7a).…”

Silicide Coating Fabricated by HAPC/SAPS Combination to Protect Niobium Alloy from Oxidation

“…By EDS analysis (Figure 4d), NbSi 2 is further confirmed for the HAPC-deposited coating. No intertransition layer, such as Nb 5 Si 3 reported in other literatures, 10,12 is detected due to the rather short deposition duration. 33 Due to the inward diffusion of silicon atom perpendicularly to the surface, it reveals a typical column crystallization for NbSi 2 coating as shown in Figure 4c.…”

Degradation Properties of Refractory MoNbTaVW High-Entropy Alloys with Simultaneous Si/Al Pack Cementation Coatings Under High-Temperature Flame Tests

“…Pack cementation coatings, which is a type of chemical vapor deposition coating process, have been studied to improve the oxidation resistance of alloys containing refractory elements [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. The pack cementation coatings form a silicide or aluminide coating layer on the surface using Si and/or Al as a coating source and form a protective oxidation layer as a ceramic layer such as SiO 2 or Al 2 O 3 in high-temperature oxidizing environments.…”

“…The pack cementation coatings form a silicide or aluminide coating layer on the surface using Si and/or Al as a coating source and form a protective oxidation layer as a ceramic layer such as SiO 2 or Al 2 O 3 in high-temperature oxidizing environments. The protective layer prevents the penetration of oxygen so that the mechanical properties of the specimen can be maintained in high-temperature environments [1,2,4,[9][10][11][12][13][14][15][16][17]. K.S.…”