Preparation and Damping Properties of NiCrAlY Coating by Arc Ion Plating
NiCrAlY coatings were prepared on stainless steel substrates by arc ion plating technique.The coating samples were tested in phase,surface morphology,micro-determination chemical composition,storage modulus and loss modulus.The results showed that uniform NiCrAlY coating can be fabricated on steel substrate by arc ion plating technique.The variation of arc current during the preparation influenced the surface topography and chemical constitution of the coatings to a certain extent,while the influence on the sample phases was not observed.The testing results of storage modulus and loss modulus were obtained to study the damping characteristics of NiCrAlY coatings.It approved that the damping properties of the substrates are prominently ameliorated by NiCrAlY coating.
Abstract Cation concentration profiles in solid—solution scales on NiCo alloys have been calculated by making use of Wagner's theoretical analysis. As a result of the computation method used, it becomes unnecessary to incorporate experimental values in the calculation for either the parabolic rate constant, k p , or the boundary conditions of the cation profile. The agreement between the independently determined theoretical and experimental cation profiles provides strong support for Wagner's model. The calculated variation of k p with alloy composition is also in agreement with the experimental data.