Carbon Fiber C / C - Sic Friction Materials Mechanical Properties

The short carbon fiber reinforced C/C-SiC friction material madethrought the Molding-in-suit reaction processing, which is a hopefulindustrial production processing, the merits of it are short cycle, low cost.On this article, C/C-SiC friction material made throught theMolding-in-suit reaction processing, The influence of fibers distributing,fibers length, fiber volume, and successive carbonization disposal onmechanical properties were investigated by measuring the bending,compressive and impact strength, and the fracture surface morphologieswere observed and analyzed through macroscopically photographs andscanning electron microscope. The effect factors of mechanical propertiesand the fracture mechanism were been realized. The conclusions can bedrawn as the following:(1) The distributing of fibers in matrix can influence the combine offiber and matrix. Bundle fibers distributing have few interfaces offiber/matrix, and porous on the bundle fibers. Dispersing fiberdistributing have compact fill between single fibers, more interface offiber/matrix. The strength of composite can been improved by the fiberspull out and brittle fracture which absorbed large numbers of fractureenergy.(2) Fiber length is an importance factor which influenced themechanical properties of short fibers reinforced composites. Fibers have acritical length which has the most use of the fiber. When fiber is longerthan critical length, fibers fracture was the mostly reasons of compositedamage. When fiber is shorter than critical length, the split and wreck ofmatrix cause the composite damage. In my research experiments, theselective fiber length are 2mm, 5mm, 8mm and 12mm, the result showthat when fiber length is 5mm, composites have the best mechanicalproperties. Flexural, vertical compressive, parallel compressive andimpact stress separately were 59.06MPa,147.03MPa,134.25MPa,2.45KJ.m^-2。(3) When selective fiber volume is 5％, 10％and 15％, with the fiber volume increasing, Flexural, compressive and impact stress ofcomposite have improved. Fibers can't sustain and reinforce the matrixwhen fiber volume is lower. The damage of composite is cause by thesplit of the matrix. Fiber volume increase, fibers become the sustentationframework of matrix, and the combine with matrix been strengthen, theresist of composite to lode had enhance.(4) Succession carbonization disposal of composites enhance thecompressive strength, decrease the impact strength and brittleness greatlybeen increased the same as. Resin was carbonized and left many poresand flaws which become breakpoints and available route way with cracksdevelopment of composite.(5) The flexural fracture mechanism of short fibers reinforcedcomposite were pulled out, spilt or brittle failure of the fibers, and thethe brittle fracture of carbon and silicon carbide matrixes. Compressiveshow brittle fracture mechanisms. Vertical compressive specimens weredestroyed by shear stress with matrix and fibers layer. The parallelcompressive specimens were destroyed by split on the interface of fiberlayer and matrix.The breakage of impact is brittle fracture cause by thebreak of fibers and the fracture of matrix...