Effect of boron doping on fracture behavior of carbon fiber reinforced lithium aluminosilicate glass ceramics matrix composites

Abstract

Boron doped carbon fibers reinforced lithium aluminosilicate matrix composites (Cf/LAS) were prepared by slurry infiltration combining with hot pressing procedure. The doping of boron significantly enhances the fracture toughness and fracture work of the Cf/LAS composites, which could reach the highest fracture toughness of 25.0±0.4MPam1/2 and the work of fracture of 24.5±2.8kJ/m2, respectively. The work of fracture of boron doped Cf/LAS composites is 2.2 times of that of the boron free Cf/LAS composites. The fracture mode of Cf/LAS composites changed from ductile fracture to brittleness fracture with increasing the boron content from 0 to 4wt%. The connection of the fracture behavior and the interfacial microstructure was examined to establish a direct relationship among interfacial microstructure, interfacial chemistry and fracture behavior of the studied composites.