TY - GEN
T1 - Comprehensive study of the process - Property correlations
T2 - Proceedings of the International Thermal Spray Conference
AU - Vaidya, A.
AU - Streibl, T.
AU - Li, L.
AU - Sampath, S.
AU - Gouldstone, A.
AU - Kovarik, O.
AU - Greenlaw, R.
PY - 2004
Y1 - 2004
N2 - Thermal spray coatings exhibit a wide variety of microstructural characteristics that lead to variation in their functional properties. A complete understanding of the plasma spray process includes examination of the particle flame interaction, particle impact (to form the splats) and the particle - substrate interaction during coating deposition. This link has been established by using diagnostic tools in conjunction with a splat collection shutter and an 'in-situ' curvature measurement instrument. In this study, a commercial grade molybdenum (Mo) powder was plasma sprayed and the spray stream was characterized for resulting particle state. A 'splat map' was deposited through a 'spray stream guillotine' to capture the fingerprint of the plume cross section. Subsequently, coatings were deposited at these spray conditions on a newly developed 'in-situ' curvature measurement instrument to measure coating stresses and to estimate the coating modulus. Splats and coatings were subsequently characterized by micro-diffraction (for splat residual stresses), nano and micro-indentation for elastic and elastic-plastic properties and by electron microscopy. This complete history of the process followed by splat and coating characterization provides insight into the correlation between processing parameters, resultant particle states and final coating properties. The role of particle temperature and velocity on the splat (and coating) morphology and residual stress is explained in the results.
AB - Thermal spray coatings exhibit a wide variety of microstructural characteristics that lead to variation in their functional properties. A complete understanding of the plasma spray process includes examination of the particle flame interaction, particle impact (to form the splats) and the particle - substrate interaction during coating deposition. This link has been established by using diagnostic tools in conjunction with a splat collection shutter and an 'in-situ' curvature measurement instrument. In this study, a commercial grade molybdenum (Mo) powder was plasma sprayed and the spray stream was characterized for resulting particle state. A 'splat map' was deposited through a 'spray stream guillotine' to capture the fingerprint of the plume cross section. Subsequently, coatings were deposited at these spray conditions on a newly developed 'in-situ' curvature measurement instrument to measure coating stresses and to estimate the coating modulus. Splats and coatings were subsequently characterized by micro-diffraction (for splat residual stresses), nano and micro-indentation for elastic and elastic-plastic properties and by electron microscopy. This complete history of the process followed by splat and coating characterization provides insight into the correlation between processing parameters, resultant particle states and final coating properties. The role of particle temperature and velocity on the splat (and coating) morphology and residual stress is explained in the results.
UR - https://www.scopus.com/pages/publications/10444255477
M3 - Conference contribution
AN - SCOPUS:10444255477
SN - 0871708094
T3 - Proceedings of the International Thermal Spray Conference
SP - 143
EP - 147
BT - Proceedings of the International Thermal Spray Conference
Y2 - 10 May 2004 through 12 May 2004
ER -