The Boeing Company

Spirit Aerosystems, Inc.

Leonard Lloyd Baca

John Michael Welch

Steven Fillmore Hanson

Robert Alexander Coleman

Thomas D Popp

Timothy Dean King

A system and method for forming a hollow, complex, monolithic composite part. Composite material may be placed around the mandrel, then an internal impermeable membrane may be placed into and/or through tunnels formed in the mandrel. Next, an external impermeable membrane may be placed around the composite material and sealed against itself and the internal impermeable membrane such that the mandrel and the composite material are both contained in an airtight manner between the internal and external impermeable membranes. Air may then be removed from within the sealed impermeable membranes, compressing the impermeable membranes against the mandrel and/or the composite material. The consolidated composite material may be hardened to form the composite part. Finally, the impermeable membrane may be removed from around the hollow composite part and from within the mandrel, followed by removal of the mandrel from within the composite part by breaking it up into smaller pieces.

Method and system for forming a complex monolithic thermoset part

A method of forming a composite acoustic panel (,). The method begins by arranging a perforated sheet (,) on a convex lay-up mandrel (,), arranging a core material (,) on the perforated sheet (,), and curing the perforated sheet (,) and the core material (,) to form a composite acoustic core (,) having a lay-up mandrel side and an opposite upper side. Composite sheets (,) are then arranged on a concave lay-up mandrel. The composite acoustic core (,) is arranged on the composite sheets (,) with the opposite upper side of the acoustic core (,) against the composite sheets (,). The composite acoustic core (,) and the composite sheets (,) are then cured so as to form the acoustic panel (,). A sacrificial sheet (,) can be added to upper side of the core material (,) prior to curing the perforated sheet (,) and the core material (,). The sacrificial sheet (,) preferably has a low coefficient of thermal expansion. The sacrificial sheet (,) is machined off as the upper side of the core material (,) is shaped. The use of the sacrificial sheet (,) permits the acoustic core (,) to maintain its shape during curing without warpage from residual thermal stresses (R). The perforated sheet (,) thus maintains a contour that is substantially matched to the outer surface of the convex lay-up mandrel (,).

Method for forming a composite acoustic panel

Growing community of inventors

Mulvane, KS, United States of America

Leonard Lloyd Baca