2022/10/14
Multiple Jigs for the Machining of High-cost Titanium Aircraft Parts (Part 2)
Centre de métallurgie du Québec (CMQ), Howmet Aerospace, A7 Integration, Coalia, Electro-Kut, École de technologie supérieure (ÉTS), SphèreCo Technologies, TRAF Produits Industriels. (2018-2022).
Objectives
To optimize a machining jig that reduces costs and production time while maintaining or improving its properties through Additive manufacturing (AM).
Background
Machining aerospace parts requires a variety of complex and diverse fixtures and tools. The process often involves significant costs and lead times to achieve the required precision. Machining lead times are further amplified by the high demand. Funded by the Natural Sciences and Engineering Research Council (NSERC) and the Consortium de recherche et d’innovation en aérospatiale au Québec (CRIAQ), the objective behind the MANU-1707 project titled “Création de stratégies démonstratrices de conception et de fabrication hybrides pour l’outillage aérospatial” was to evaluate and integrate AM into tooling production processes when machining aerospace parts while reducing costs and production lead times.
The challenge
AM is often considered too expensive when producing parts that do not provide a great deal of value-added. Inconel and titanium aerospace parts with complex and optimizable geometries, however, are often considered ideal candidates for AM. Machining jigs made from 6061 or 4340 aluminum tend to be less so. This is partly due to the lower cost of the material intended for machining when producing the jig; machining 90% of a steel part is typically less challenging than doing the same for a titanium part. If we consider machining costs alone, a commonly used AM design rule states that a part produced through machining will generally be less expensive than one produced through AM. Plus, a jig’s geometry often shows less flexibility to topological optimization due to geometric constraints from the parts they hold, as well as by other sections of the jig. The jigs analyzed in this case study involved high production costs, which the project sought to reduce. It should be noted that these jigs belonged to a set of comparable fixtures that could be optimized through similar methods.