High-Speed Contact Study between a Ti-6-Al-4V Tool and an Abradable Coating Using Ballistic Benches and a Dynamic Compensation Approach

To reproduce severe and short-lived contacts like those occurring between the blade tip of an aircraft engine and the abradable material coated inside the engine casing, ballistic benches can be used. These devices allow to achieve a large range of velocities and thus, they allow the study of the abrasion process and the resulting wear of these kind of sealing materials. The Al-based abradable characterized within this work have been grown by atmospheric plasma spraying on a titanium substrate that was afterwards mounted on top of an aluminum projectile. Due to the short-lived forces occurring during these kind of contacts, the dynamic behavior of the device itself strongly affects the measured force signals. In order to overcome these dynamic distortions, we present a compensation approach able to perform a virtual extension of the available dynamometer bandwidth. This approach is based on an inverse-filtering of the response signal by using a 3 × 3 force-to-force transmissibility matrix function. The validated compensation approach was used to characterize the relation between the full three-dimensional measured contact-force and the specimen wear occurring during the abradable/Ti-6-Al-4V high-speed interaction.