Influence of air plasma spraying process parameters on the thermal barrier coating deposited with micro- and nanopowders

Abstract This study investigates the optimal conditions to deposit a thermal barrier coating using micro- and nanopowders in air plasma spraying (APS) process. The influence of APS process parameters on thickness, porosity hardness yttria-stabilized zirconia (YSZ; ZrO 2 × 8Y O 3 ) coatings deposited with single-electrode gun was determined. temperature velocity melted particles were determined by DPV diagnostic system decrease number experimental processes. current H flow rate changed this research. Metco-6700 YSZ micropowder has already been used spray physical vapor deposition. results suggest possibility it for APS. powder are characterized high (2,700°C–2,900°C) speed (>380 m/s). highest thickness obtained 6 NLPM (normal liter per minute) 800 A current. Difficulties observed feeding at higher flow. showed that APS, deposition Metco-6609, nanopowder normally suspension spraying, is possible. In research, fed carrier gas. around 40 μm thick had porosity. lowest 600 12 NLPM. coatings, unmelted spherical also visible.