论文部分内容阅读
Thermal Barrier Coating(TBC)is necessary to increase turbine inlet temperature of a high efficient gas turbine for a power station.The atmospheric plasma spraying is employed to process a well-established technology in the field of surface coating.Suspension plasma spraying is expected to have higher flexibility in particle size of processed material than conventional plasma spraying.Therefore microstructural feature of coating by can be varied by the parameters of suspension plasma spraying,such as molten droplets of material.AIST is trying development of the axial feeding type of suspension plasma gun with thin coaxial twin fluid atomizer.Atomization of ethanol suspension of solid particles is one of the important factors controlling the coating quality.Therefore the spray of zirconia-ethanol suspension from the thin coaxial twin fluid atomizer with new p-torch was investigated.The outer and inner diameter of the outer tube is 1.0mm and 0.7mm respectively,the outer and inner diameter of the inner tube is 0.4mm and 0.2mm respectively.Air is used instead of argon gas as atomizing gas.Flow rate of air is from 0.065g/s to 0.13g/s.Mass fraction of zirconia of zirconia-ethanol suspension is from 0 to 15wt%.Injection pressure of suspension is 0.1 to 0.3MPa.Sauter Mean Diameter of spray of zirconia-ethanol suspension is not stable due to deposition of zirconia particles on the inner wall of the flow path.Sauter Mean diameter increases with injection pressure of suspension due to increase of suspension mass flow rate..Sauter mean diameter decreases with increase of the mass flow rate of atomizing air.Sauter mean diameter is almost constant against increase of zirconia-ethanol suspension concentration.