Interaction between machining and new fixturing principles for aerospace structures

Abstract

Automated assembly is generally confined to mass production environments such as the manufacture of cars and white goods. Even in this environment high-level automated assembly is restricted to the OEMs where production volumes are high and flexibility and the ability to quickly reconfigure systems are not major drivers.

In the aerospace industry the problem is further complicated by the move to thin walled monolithic parts and the increasing use of composite structures. Monolithic structures have been introduced to reduce the costs of assembling large numbers of components. Although the benefit of using monolithic parts is a large reduction in overall manufacturing costs the downside is a more difficult component to handle and assemble. In addition, there are thin walled components with sometimes-internal stresses and in our case made of nickel based alloys, which only can be cut with difficulties. Machining the flexible structure and maintaining close tolerance is difficult, transferring to assemble is difficult as well.

In this paper a theoretical analysis regarding static, dynamic and thermal behaviour of an aerospace part (nozzle-guide-vans) starting from macro scale effects up to micro scale domain mechanics evaluation is going to be presented. This analysis allows to evaluate different effects related to anisotropy, non-linearity and damping properties, which can influence the final results of analysis.

The influence of different grain orientations of the grinding process to the mechanical properties in surfaces has been included in the investigations.