# Experimental Study on Anti-Wrinkling Performance of TA1 Titanium Thin Sheet Assisted by Ultrasonic Vibration

## TL;DR

This study explores how ultrasonic vibrations can reduce wrinkling in titanium sheets during stamping, improving the quality of hydrogen fuel cell components.

## Contribution

The novel use of ultrasonic vibration to suppress wrinkling in thin titanium sheets during stamping is experimentally investigated.

## Key findings

- Ultrasonic vibration reduces forming load and suppresses wrinkling in TA1 titanium sheets.
- Thinner sheets show reduced anti-wrinkling ability and experience secondary wrinkling during plastic deformation.
- Vibration energy lowers yield and flow stress, promoting wrinkling during elastic deformation.

## Abstract

TA1 titanium bipolar plates for hydrogen fuel cells are prone to plastic instability phenomena such as wrinkling during the stamping process, which adversely affects the forming quality. This study applies an ultrasonic-vibration energy field, aligned with the direction of stretching, in a plate diagonal tensile testing scenario based on the Blaha effect. The impact of varying thicknesses and vibration amplitudes on the anti-wrinkling performance of TA1 titanium sheets is investigated. Through a combined analysis of load–displacement curves and wrinkle height measurements using a super-depth-of-field microscope, by examining the forming load, the onset of wrinkling, and the wrinkle height at buckling locations, this study explores the deformation behavior of the thin sheet and the wrinkle suppression mechanism under the coupled effects of the ultrasonic-vibration field and scale. The results show that as the thickness decreases, the anti-wrinkling ability of the TA1 titanium sheet diminishes. The ultrasonic-vibration energy field reduces the yield stress and flow stress of the material, promoting wrinkling during the elastic deformation stage. Moreover, the 0.075 mm thick TA1 titanium sheet experiences local secondary wrinkling during the plastic deformation stage. Additionally, the ultrasonic-vibration energy field effectively reduces the forming load of the sheet and suppresses wrinkling within a certain range of amplitudes. These findings provide experimental evidence for the ultrasonic-vibration-assisted stamping process of titanium bipolar plates.