Automated Thermal Impedance Scanning (ATIS) System for NDE (Nondestructive Examination) of Coatings on Turbine Engine Parts.

摘要

Thermal spray coatings have been gaining increased application throughout industry in recent years. The quality of the coating-to-substrate bond is of prime importance in many of these applications. This paper describes an Automatic Thermal Impedance Scanning (ATIS) system to provide completely automatic nondestructive examination (NDE) for thermal spray coating bonds in turbine engine parts. This system is being installed as part of an experimental automated production facility at the Teledyne CAE plant in Gainesville, GA. Thermal spray processes utilize a hot, high velocity gas stream to heat either a powder or wire to a plastic or molten state. The high velocity gas accelerates the hot particles to a high velocity before they are allowed to impact the surface to be coated. These particles adhere to the previously roughened surface (grit blast) by predominantly mechanical means. In some cases, depending on the part material and material sprayed, a quasi metallurgical bond can be formed. 19 figs. (ERA citation 14:029111)