Tensile and compression test of carbon/epoxy composite laminate under combined action of laser irradiation and load

The failure behaviour of T700/603 carbon fibre/epoxy composite laminates subject to pre-load and laser irradiation was tested. The effect of main parameters on failure time of specimens has been studied. Specimens with different thickness were kept in tension or compression pre-load using a specially designed load holding device. Meanwhile, CO2 continuous wave laser beam was irradiated on specimens until they were damaged. Through the experiments, we obtained the relationship between the failure time of the specimen and the pre-load is approximately linear when the laser power density and the thickness were constant; the relationship between the failure time of the specimen and the laser power density is approximately exponential when the pre-load and the thickness were unchanged; the relationship between the failure time of the specimen and the thickness is approximately quadratic function when the pre-load and the laser power density were fixed. The failure mechanism of the pre-tension specimen is different from that of the pre-compression specimen. In the pre-tension experiment, the pre-tension specimen was pulled off in a spallation, whereas it collapsed by delaminating and buckling in the pre-compression experiment. The fitting equations present a prediction of lifespan of the carbon/epoxy composite-laminated structures subject to pre-load and laser irradiation.