E. H. Jordan, M. Gell, B. Cetegen, P. Bonzani, X. Ma, F. Wu, D. Chen, N. Padture, University of Connecticut, Storrs, CT
Solution precursor plasma spray allows the creation of coatings directly from chemical precursors thus avoiding the difficult task of making parable powders. To date this process has been based on injecting chemical into a DC plasma torch. The process has proven to be useful in making vertically cracked thermal barrier coatings and has shown special advantages for making thick thermal barrier coatings (up to 3 mm thick). Most recently the process has been modified to produce dense crack free coatings. This development was enabled by and improved understanding of the process and especially an understanding of the means by which desirable cracks are created in thermal barrier coatings. A crack free yittria stabilized zerconia coatings in excess of 98% dense and a hardness of 1000 HV has been produced. These developments will be reviewed. Very recently, solution precursor plasma spray has been implemented in an HVOF system with the associated advantages of axial injection and high deposition velocity. At the same time the gas temperature are lower presenting challenges for making very high melting temperature oxide ceramic coatings. Recent results from this new version solution precursor plasma spray will be presented including the deposition of dense titania coatings.
Summary: Abstract- Solution precursor plasma spray allows the creation of coatings directly from chemical precursors thus avoiding the difficult task of making parable powders. To date this process has been based on injecting chemical into a DC plasma torch. The process has proven to be useful in making vertically cracked thermal barrier coatings and has shown special advantages for making thick thermal barrier coatings (up to 3 mm thick). Most recently the process has been modified to produce dense crack free coatings. This development was enabled by and improved understanding of the process and especially an understanding of the means by which desirable cracks are created in thermal barrier coatings. A crack free yittria stabilized zerconia coatings in excess of 98% dense and a hardness of 1000 HV has been produced. These developments will be reviewed.
Very recently, solution precursor plasma spray has been implemented in an HVOF system with the associated advantages of axial injection and high deposition velocity. At the same time the gas temperature are lower presenting challenges for making very high melting temperature oxide ceramic coatings. Recent results from this new version solution precursor plasma spray will be presented including the deposition of dense titania coatings.
