Experimental Evaluation of CF/PC Interfacial Tensile Strength Based on Modified Cruciform Test

: In this study,we applied a modified cruciform test to the evaluation ofthe interfacial tensilestrength (IFTS)ofthecarbon fiber (CF)/polycarbonate(PC)interfaceand evaluated the effectiveness of the evaluation method via in situ observation. Although the interfacial shear strength has been extensivelyanalyzed in previous works with thermosetting plastics,fewstudies have evaluated IFTS ofthermoplastics,for instance,PC.However,previous reports have stated that the cruciform test is not suitable when the fiber transverse modulus is much lower than the matrix modulus.Therefore,in thepresent study,themodified cruciform test wascarried out with specimen in which loading armsarereinforced with CF/PC cross-plylaminatesin orderto induce stress concentration at the fiber surface. Debonding was observed and was found to instantly propagatealong thefiber,and theIFTS was calculated as 63.1±12.6MPa on average.Thus,this investigation hasrevealed theIFTS oftheCF/PC composite,and theeffectivenessofthemodified test to evaluatethermoplasticcomposites was confirmed.