This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Application of DFSS Taguchi Method to Design Robust Shock Tower
ISSN: 0148-7191, e-ISSN: 2688-3627
To be published on April 06, 2021 by SAE International in United States
Event: SAE WCX Digital Summit
Design for Six Sigma (DFSS) is an essential tool and methodology for innovation projects to improve the design/process and performance of a product. This paper aims to present an application of DFSS Taguchi Method on an automotive/vehicle component, High pressure die casting (HPDC) technology made Cast Aluminum Front Shock Tower. During the vehicle life, Shock Tower transfers the road high impact loads from the shock absorber to the body structure. Proving Ground (PG) and washout loads are often used to assess part strength, durability life and robustness. The initial design was not meeting the strength requirement for washout abusive loads. Project identified Eight parameters (control factors) to study and to optimize the initial design. Simulation results confirmed that all eight selected control factors have an effect on the part design and could be used to improve the strength and performance of Shock Tower. Non-dynamic Smaller-the-Better ideal function was considered for this project to reduce stress, which contributes to the higher durability life of the part. The number of Simulation decks were generated using the L18 Orthogonal Array. Optimized front shock tower design met the strength requirement for 10% higher magnitude washout loads. The Optimum Design improved part robustness by 9.6 dB (actual), which is equivalent to 62% variability reduction compared to the initial design. Key control factors that will enhance part strength are; shock tower material type, rib thickness, material addition at the rib/collar junction, spacer plate gauge, and diameter and collar height. One of the objectives of the project was to study the effect of several Shock Tower materials for this application, including HPDC alloys such as Aural-2, Silafont-36, Magsimal-59 and magnesium AM60B which showed improvement in part strength and durability. Besides, strength and ductility of AM60 material can be further improved by adopting the High-Pressure Supper Vacuum Die Casting process. Keyword: Shock tower, Taguchi method, Optimization