Oxidation behavior of thermal barrier coatings modified by laser remelting

Abstract In this study, a bond coat (Ni-22Cr-10A1-1Y (wt%)) and a top coat (Zr0 2 -7.5 wt% Y 2 O 3 ) were deposited on 304 stainless steel by air plasma spraying and then processed with either single laser remelting (SLR) or double laser remelting (DLR) treatment. Preheating specimens at 950 °C in the SLR treatment reduced depressions and the width of cracks in the top coat. A recently developed DLR treatment, in which zirconia powder in the form of a colloidal suspension was applied after SLR and then laser remelted again, helped to lower the extent of surface defects in the top coat significantly. Oxidation tests at 1200 °C indicated that the DLR specimens had a better oxidation resistance than the SLR and the plasma-sprayed specimens.

[1]  A. Grimaud,et al.  Residual stress evolution during the thermal cycling of plasma-sprayed zirconia coatings , 1996 .

[2]  R. Rawlings,et al.  Pulsed laser sealing of plasma-sprayed layers of 8 wt % yttria stabilized zirconia , 1992, Journal of Materials Science.

[3]  A. Petitbon,et al.  Laser surface sealing and strengthening of zirconia coatings , 1991 .

[4]  Joseph R. Davis.  Properties and selection : nonferrous alloys and special-purpose materials , 1990 .

[5]  R. Rawlings,et al.  Operating regimes for laser surface engineering of ceramics , 1992 .

[6]  N. Iwamoto,et al.  Surface treatment of plasma-sprayed ceramic coatings by a laser beam , 1988 .

[7]  T. Rhys-Jones,et al.  The use of thermally sprayed coatings for compressor and turbine applications in aero engines , 1990 .

[8]  Carl E. Lowell,et al.  Failure mechanisms of thermal barrier coatings exposed to elevated temperatures , 1982 .

[9]  H. Reiter,et al.  Residual stresses in ZrO2-8%Y2O3 plasma-sprayed thermal barrier coatings , 1988 .

[10]  T. Hanabusa,et al.  X-Ray residual stress measurement of laminated-coating layers produced by plasma spraying , 1993 .

[11]  B. Wu,et al.  Degradation Mechanisms of ZrO2–8 wt% Y2O3/Ni‐22Cr‐10Al‐1Y Thermal Barrier Coatings , 1989 .

[12]  C. Bartuli,et al.  Pulsed laser treatment of plasma-sprayed thermal barrier coatings: effect of pulse duration and energy input , 1992, Journal of Materials Science.

[13]  I. Zaplatynsky.  Performance of laser-glazed zirconia thermal barrier coatings in cyclic oxidation and corrosion burner rig tests☆ , 1982 .

[14]  Subra Suresh,et al.  An experimental and numerical study of deformation in metal-ceramic composites , 1989 .

[15]  R. Jones,et al.  The development of hot-corrosion-resistant zirconia thermal barrier coatings , 1991 .

[16]  Robert A. Miller,et al.  Current status of thermal barrier coatings — An overview , 1987 .

[17]  L. Lelait,et al.  Microstructural Investigations of Plasma-Sprayed Yttria Partially Stabilized Zirconia TBC (In Relation to Thermomechanical Resistance and High-Temperature Oxidation Mechanisms) , 1994 .

[18]  H. J. Hucek,et al.  Structural alloys handbook , 1986 .

[19]  P. Scardi,et al.  Residual stresses in plasma sprayed partially stabilised zirconia TBCs: influence of the deposition temperature , 1996 .

[20]  D. Ruckle.  Plasma-sprayed ceramic thermal barrier coatings for turbine vane platforms☆ , 1980 .

[21]  H. Steffens,et al.  Characterization and thermal shock testing of yttria-stabilized zirconia coatings , 1987 .

[22]  A. Ohmori,et al.  Liquid-Mn sintering of plasma-sprayed zirconia-yttria coatings , 1994 .