Session: Virtual Presentations in Acoustics, Vibration, and Phononics

Paper Number: 95365

95365 - Acoustic Emission Detection of Circumferential UV-Mechanical Failure of Glass Epoxy Composites 

Glass composite cylinders is an important development direction of gas storage and transportation, but composite cylinders will be affected by environmental factors such as humidity, heat, ultraviolet, smoke and so on. It is a challenging task to understand the damage and failure of glass epoxy composites after UV aging in practical application. Therefore, in this paper, the circular glass epoxy composite specimens have been prepared and subjected to UV aging experiments at different times (0 h, 24 h, 48 h, 96 h, 192 h, 288 h, respectively). Subsequently, acoustic emission and X-ray computed tomography techniques are used to evaluate the damage and failure behavior of specimens with different aging time under circumferential tensile loading. The mechanical results show that after ultraviolet radiation, the strength of glass fiber composite materials first rises and then decreases. Among them, the radiation time is between 24 h and 48h, and the tensile strength and interlaminar shear strength increase very slowly. When the irradiation time is 288 h, the tensile strength of the composite is lower than that without ultraviolet radiation, and the interlaminar shear strength is the opposite. However, due to the fact that the additional bending can not be overcome when the sample is stretched, the strength test is only the apparent result. The experimental results of acoustic emission show that with the increase of aging time, the number of acoustic emission events gradually decreases, but the accumulated acoustic energy of acoustic emission signal increases, which indicates that the longer the aging time, the more severe the damage during loading, and the easier it is for the specimen to fail and fracture earlier. The distribution of failure modes caused by circumferential mechanical properties test of specimens can be characterized by X-ray computed tomography. The failure modes of specimens with different aging time have certain differences, which can be roughly divided into matrix cracking, fiber/matrix fracture, delamination and fiber fracture. The longer the ultraviolet radiation time is, the more serious the interlaminar cracking and the greater the dispersion of the glass fiber in the composite, the more brittle the matrix is, the lower the bonding strength between the fiber and the matrix, and the worse the interface performance. The specimens aged for 192 h and 288 h show explosive failure in tensile fracture, which is no longer suitable for X-ray computed tomography. In addition, the two complementary nondestructive testing technologies can effectively monitor the damage process inside and outside the sample, and can provide the basis for health monitoring in composite cylinders.

Presenting Author: Yilin Yuan China Special Equipment Inspection and Research Institute;Key Laboratory of Nondestructive Testing and Evaluation for State Market Regulation

Presenting Author Biography: Yilin Yuan, mainly engaged in non-destructive testing, scientific and technological projects and achievement management, research direction is the acoustic emission of composite materials.

Authors:

Yilin Yuan China Special Equipment Inspection and Research Institute;Key Laboratory of Nondestructive Testing and Evaluation for State Market Regulation
Gongtian Shen China Special Equipment Inspection and Research Institute
Fei Xie China Special Equipment Inspection and Research Institute
Junjiao Zhang China Special Equipment Inspection and Research Institute;Key Laboratory of Nondestructive Testing and Evaluation for State Market Regulation
Pengcheng Gan China Special Equipment Inspection and Research Institute
Yongna Shen China Special Equipment Inspection and Research Institute;Key Laboratory of Nondestructive Testing and Evaluation for State Market Regulation
Kuan Su China Nuclear Power Engineering Co., Ltd