Distortion Modeling of Airframe Components

Structural airframe design is driving to maximize structural unitization.  This enables appreciable cost, weight savings, and improved buy-to-fly in large structural components.  However, as parts become larger and more unitized the demands imposed on the design and manufacturing process increases.  While it may be feasible to compensate for distortion during assembly of many small parts, large unitized structure lacks the degrees of freedom to compensate and is less forgiving of distortion.  Distortion can be caused by material bulk stresses resulting from processing operations and/or by local near-surface machining induced stresses.  Typically additional machining operations and setups are added in a time-consuming and costly approach to minimize the effects of part distortion.  There is a need to understand the effects of materials processing and machining on distortion and to predict, minimize, and control these distortions.  This presentation will review progress that has been made on the machining modeling side to relate material and machining process to distortion in airframe parts.