Linear friction weld process monitoring of fixture cassette deformations using empirical mode decomposition

Bakker, Otto Jan; Gibson, C,; Wilson, Peter; Lohse, Niels; Popov, Atanas A.

Abstract

Due to its inherent advantages, linear friction welding is a solid-state joining process of increasing importance to the aerospace, automotive, medical and power generation equipment industries. Tangential oscillations and forge stroke during the burn-off phase of the joining process introduce essential dynamic forces, which can also be detrimental to the welding process. Since burn-off is a critical phase in the manufacturing stage, process monitoring is fundamental for quality and stability control purposes. This study aims to improve workholding stability through the analysis of fixture cassette deformations. Methods and procedures for process monitoring are developed and implemented in a fail-or-pass assessment system for fixture cassette deformations during the burn-off phase. Additionally, the de-noised signals are compared to results from previous production runs. The observed deformations as a consequence of the forces acting on the fixture cassette are measured directly during the welding process. Data on the linear friction-welding machine are acquired and de-noised using empirical mode decomposition, before the burn-off phase is extracted. This approach enables a direct, objective comparison of the signal features with trends from previous successful welds. The capacity of the whole process monitoring system is validated and demonstrated through the analysis of a large number of signals obtained from welding experiments.

Citation

Bakker, O. J., Gibson, C., Wilson, P., Lohse, N., & Popov, A. A. (2015). Linear friction weld process monitoring of fixture cassette deformations using empirical mode decomposition. Mechanical Systems and Signal Processing, 62-63, https://doi.org/10.1016/j.ymssp.2015.02.005

• Journal Article Type: Article
• Publication Date: Oct 1, 2015
• Deposit Date: Jul 9, 2015
• Publicly Available Date: Oct 1, 2015
• Journal: Mechanical Systems and Signal Processing
• Print ISSN: 0888-3270
• Electronic ISSN: 1096-1216
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 62-63
• DOI: https://doi.org/10.1016/j.ymssp.2015.02.005
• Keywords: Linear Friction Welding, Process Condition Monitoring, Hilbert-Huang Transform, Time-Frequency Analysis, Empirical Mode Decomposition, Non-Stationary Signal
• Public URL: https://nottingham-repository.worktribe.com/output/981688
• Publisher URL: http://www.sciencedirect.com/science/article/pii/S0888327015000783