Tensile and fatigue behavior of carbon fiber reinforced magnesium composite fabricated by liquid-solid extrusion following vacuum pressure infiltration

Liquid-solid extrusion following vacuum pressure infiltration (LSEVI) technique is a new technology, which is suitable for the fabrication of carbon fiber reinforced magnesium composite (Cf/Mg composite). This work details an experimental investigation on understanding the fatigue performance of Cf/Mg composite fabricated by LSEVI technique. The S-N curve of the composite was determined and the fatigue behavior considering different loading levels and cycles was studied. Moreover, the fracture surfaces and microstructures of test samples were examined to understand the fatigue damage mechanism. The investigation finds that the residual tensile strength of specimens that survived during fatigue test was enhanced with the increase in fatigue cycles and applied stress. In addition, fatigue loading could change the tensile behavior of the composite, and a yielding point was observed at stress-strain curves of specimens which survived during fatigue test. Observations of the fracture surfaces revealed that more fibers were pulled out with the increase in fatigue cycles and applied stress.