Mode Ι fracture toughness of adhesively bonded composite joints under high loading rate conditions

ABSTRACT

The purpose of this paper is to investigate the mode I fracture behavior of adhesively bonded composite joints under high loading rate conditions. A dual electromagnetic split Hopkinson pressure bar system was established to apply symmetric dynamic loading on the double cantilever beam (DCB) specimens at 15 m/s and 30 m/s. The dynamic fracture toughness was then evaluated using an experimental-numerical approach and compared to the results of quasi-static loading rate (2 × 10⁻⁵ m/s and 2 × 10⁻⁴ m/s). Results indicate that high loading rate has obvious effects on the fracture toughness of composite joints. When the loading rate increases to 30 m/s, the mode I fracture toughness can reach a value of 1645 J/m², which is 119% higher than that of quasi-static conditions. At last, fracture surface inspections using scanning electron microscopy (SEM) were conducted to reveal such an effect.

KEYWORDS:

• Composite joints
• mode I fracture toughness
• high loading rate

Acknowledgements

This research was supported by the National Natural Science Foundation of China (No. 12102336) and supported by the Natural Science Foundation in Shaanxi Province of China (No. 2021JQ-005).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [12102336]; the Natural Science Foundation in Shaanxi Province of China [No.2021JQ-005].