EFFECTS OF CARBON NANOTUBE DEPOSITION TIME TO CARBON FIBER ON TENSILE LAP-SHEAR STRENGTH OF RESISTANCE WELDED CFRTP

Carbon Nanotube (CNT) grafted carbon fibers were used for the heating element of resistance welding, and the effect of CNT deposition time at deposition temperature of 600oC on the tensile lap-shear strength of resistance welded CFRTP was evaluated. The longer the deposition time became, the longer the length of CNT became. The highest tensile lap-shear strength was obtained when CNT grafted carbon fibers grafted at the deposition time of 30 minutes were used for the heating element of resistance welding because it is reported that fiber matrix interfacial properties of the carbon fiber was improved by CNT deposition to the surface of carbon fiber. In the case of the CNT grafted carbon fibers grafted at the deposition time of 60 minutes, lower tensile lap-shear strength was obtained because of the poor impregnation of the resin into the carbon fiber due to the excess CNT on the carbon fibers. The length of CNT should be controlled to obtain good mechanical properties.