Abstract: A coating thickness measurement system (10) for measuring a thickness of a coating (12) on a coated substrate (14) is provided. The coating thickness measurement system (10) may comprise a light source (16), a detector system (18), and a processor (20). The light source (16) directs a light beam (22) at an angle (26) oblique to an axis (28) of the coating (12). The light beam (22) striking the coating (12) produces a reflected light beam (36). The detector system (18) measures a reflectivity of the coating (12). The processor (20) receives the reflectivity measurement and determines the reflectivity of the coating (12). The thickness of the coating (12) is determined from the reflectivity of the coating (12).

Abstract: A method of processing a composite structure in an autoclave involves producing a layup (10) with a low density honeycomb core (12) covered by resin impregnated composite face plies (14). The layup is sealed to a mold (18) under a vacuum bag (20). The layup is then cured in an autoclave under high temperatures and pressures. A vacuum is applied between the layup (10) and the vacuum bag (20) via a vacuum port (22), thus creating a pressure differential across the bag (20). This creates a compressive consolidating force on the composite face plies (14). Volatiles emitted during curing are drawn away through the vacuum port (22). The core (12) communicates with the autoclave by means of a pressurization tube (26) which penetrates the mold (18) and into the core (12), thus eliminating the pressure differential between the core (12) and the autoclave. Autoclave pressure is communicated throughout the entire core via perforations (13) in the honeycomb core (12).