On the mixed mode I/II/III translaminar fracture toughness of cotton/epoxy laminated composites

•The mixed mode I/II/III translaminar fracture of cotton/epoxy composite was studied.•Epoxy resin and woven cotton fibers were used as the composite components.•Compact shear tension sample was loaded by a specially test setup.•Finite element method was performed to compute critical strain energy release rate.•Translaminar CSERR of the system is significant as compared to the other composites. The mixed mode I/II/III translaminar fracture of a natural fiber reinforced composites system was investigated in this paper. The specimens were made of epoxy resin and fabric cotton fibers. Compact shear tension (CTS) test configuration was utilized to determine a full range of mixed mode I/II/III translaminar critical strain energy release rate (CSERR). The CTS specimens were loaded by a novel test setup. In addition to pure modes I, II and III CSERR of cotton/epoxy system, a full series of mixed mode tests were conducted. Finite element analysis was also carried out to calculate the calibration factors related to the CSERR formulations. The pure mode I, II and III CSERR of cotton/epoxy laminates were obtained as 48.1, 57.8 and 1528.5 kJ/m2, respectively. The investigation confirms that the translaminar CSERR of cotton/epoxy laminated composites is considerable as compared to the mode I translaminar CSERR of artificial fiber reinforced epoxy systems. Hence, due to this property and some other advantages such as biodegradability, biocompatibility and sustainability of the cotton/epoxy fiber laminated composites material can be a strong candidate to use in the place of different types of wood and synthesis fiber reinforced laminates.