Method for fabricating and inspecting coatings

摘要

A method of fabrication and inspection includes depositing a coating (20) and determining at least one physical property of the coating (20) using eddy current techniques. In a detailed embodiment an abradable coating (20) having a metal volume fraction in the range of from 0.3 to 0.5 is applied to an inner circumference of a stator (30) for a gas turbine engine compressor. An eddy current probe (56) is positioned by a manipulator (54). A distance separating the probe (56) and a surface (32) of the coating (20) is measured using a frequency above one megahertz (MHz). The thickness of the coating (20) is measured by determining the rolloff frequency for the coating's complex impedance. The coating density is determined by its complex impedance at a characteristic frequency below four MHz. The density can be used as an indication of the performance of the coating (20) with respect to abradability and the erosion resistance. The measurements may also be applied as a post-process quality control technique. <IMAGE>