This paper details an investigation of the effects of oxide stringers on theβ-phase depletion behaviour in thermally sprayed CoNiCrAlY coatings.Vacuum Plasma Sprayed(VPS)Co NiCrAlY coatings,which are free of oxide st...This paper details an investigation of the effects of oxide stringers on theβ-phase depletion behaviour in thermally sprayed CoNiCrAlY coatings.Vacuum Plasma Sprayed(VPS)Co NiCrAlY coatings,which are free of oxide stringers,are used as the reference materials in comparison with High-Velocity Oxy-Fuel(HVOF)sprayed CoNiCrAlY coatings during isothermal oxidation at 1100℃.An outer layer of spinel oxides and an inner layer of alumina are formed in the as-sprayed coatings,while only a single alumina scale is found in the heat-treated coatings.Lessβ-phase depletion occurred in the HVOF coatings than in the VPS coatings.It was found that theβphases tend to coalesce at the oxide stringers in the HVOF coatings,which is likely due to the internal oxide particles and stringers acting as short diffusion barriers to tie up theβphase and inhibit theβ-phase depletion.展开更多
基金supported by Zhejiang Provincial Natural Science Foundation under Grant No.LQ18E010002Natural Science Foundation of China under Grant No.51901107+1 种基金Ningbo Natural Science Foundation under Grant No.2018A610168,2019A610176Zhejiang Qianjiang Talent Scheme under Grant No.QJD1803012。
文摘This paper details an investigation of the effects of oxide stringers on theβ-phase depletion behaviour in thermally sprayed CoNiCrAlY coatings.Vacuum Plasma Sprayed(VPS)Co NiCrAlY coatings,which are free of oxide stringers,are used as the reference materials in comparison with High-Velocity Oxy-Fuel(HVOF)sprayed CoNiCrAlY coatings during isothermal oxidation at 1100℃.An outer layer of spinel oxides and an inner layer of alumina are formed in the as-sprayed coatings,while only a single alumina scale is found in the heat-treated coatings.Lessβ-phase depletion occurred in the HVOF coatings than in the VPS coatings.It was found that theβphases tend to coalesce at the oxide stringers in the HVOF coatings,which is likely due to the internal oxide particles and stringers acting as short diffusion barriers to tie up theβphase and inhibit theβ-phase depletion.
