• Kosteski, Luis Eduardo

Abstract

The problem of toughening in brittle materials<br> reinforced by fibers is complex, involving all of the mechanical<br> properties of fibers, matrix and the fiber/matrix interface, as well as<br> the geometry of the fiber. Development of new numerical methods<br> appropriate to toughening simulation and analysis is necessary. In<br> this work, we have performed simulations and analysis of toughening<br> in brittle matrix reinforced by randomly distributed fibers by means<br> of the discrete elements method. At first, we put forward a<br> mechanical model of toughening contributed by random fibers. Then<br> with a numerical program, we investigated the stress, damage and<br> bridging force in the composite material when a crack appeared in the<br> brittle matrix. From the results obtained, we conclude that: (i) fibers<br> of high strength and low elasticity modulus are beneficial to<br> toughening; (ii) fibers of relatively high elastic modulus compared to<br> the matrix may result in substantial matrix damage due to spalling<br> effect; (iii) employment of high-strength synthetic fibers is a good<br> option for toughening. We expect that the combination of the discrete<br> element method (DEM) with the finite element method (FEM) can<br> increase the versatility and efficiency of the software developed. The<br> present work can guide the design of ceramic composites of high<br> performance through the optimization of the parameters.

Topics

• impedance spectroscopy
• simulation
• crack
• strength
• composite
• elasticity
• random
• ceramic
• discrete element method