Microstructure evolution and fracture behavior of innovative Ti-(SiC f /Al 3 Ti) laminated composites

The microstructure evolution and phase formation in novel Ti-(SiCf/Al3Ti) laminated composite were emphatically investigated via exploring the microstructures concerning different processing stages. The mechanical properties and fracture behavior of the composite were studied using compression, three-point bend (TPB) and single-edge notched beam (SENB) methods. The results indicated that the microstructure evolution of Ti-(SiCf/Al3Ti) laminated composite involved the solid-state and solid-liquid reaction of Ti and Al during hot pressing. In addition, Ti-(SiCf/Al3Ti) laminated composite generally possessed superior fracture toughness, compressive and bending strength than those of Ti-Al3Ti due to the addition of SiC fibers. The fiber breakage and interface debonding behavior was observed, confirming the expected toughening mechanisms associated with arrested and deflected behavior of the crack. Furthermore, when subjected to external bending and compressive stresses, the laminated composite displayed similar failure characteristic, containing the fragmenting of Al3Ti and cracking or buckling of Ti. Moreover, the main cracks oriented at 45° to layers in the bending and compressive specimens under perpendicular load. Nevertheless, the main crack carved all layers, propagating with a tortuous path in the edge-notched specimen along the loading direction. Additionally, the specimens were catastrophically fractured under compressive load and non-catastrophically fractured under bending load.