In this paper Mode I steady state crack growth in single crystal ferroelectric materials is investigated. Specifically, the fracture toughness enhancement due to domain switching near a steadily growing crack tip is analyzed. For this purpose, an incremental phenomenological constitutive law for single crystal ferroelectric materials is implemented within a finite element model to calculate the...

To date, high compressive ductility and energy absorption have been achieved in amorphous metal foams based on high-toughness Pdand Zr-based metallic glasses and are known to result from two extrinsic toughening mechanisms: bending of struts and shear band arrest by pores. We study here a syntactic amorphous metallic foam produced by infiltration of a bed of hollow crystalline iron spheres with...

The role of matrix ductility on the toughenability and toughening mechanism of elastomermodified, diglycidyl ether of bisphenol A (DGEBA)-based epoxies is investigated. Matrix ductility is varied by using epoxide resins of varying epoxide monomer molecular weights. These epoxide resins are cured using 4,4' diaminodiphenyl sulphone (DDS) and, in some cases, modified with 10vol % carboxyl-termina...

Fiber-reinforced plastic (FRP) composite laminates have excellent mechanical properties, corrosion resistance, and designability thus are widely used in various engineering fields. However, their interlayer performance is relatively poor due to no fiber reinforcement between the laminate layers. These layers adhered through resin bonding only, caused during usage, which results material delamin...

(2002) Numerical and experimental studies on the fracture behavior of rubber-toughened epoxy in bulk specimen and laminated composites. ABSTRACT To study the toughening mechanisms of liquid rubber (LR) and core-shell rubber (CSR) in bulk epoxy and composite laminate, experimental and numerical investigations were carried out on compact tension (CT) and double-cantilever-beam (DCB) specimens und...

Natural materials boast remarkable mechanical performances in some cases unmatched by their synthetic counterparts, and for this reason, they have become an inspiration for the development of new materials. In highperformance natural materials such as nacre, bone, or teeth, stiffness and toughness are achieved with the staggered microstructure, where stiff inclusions of high aspect ratio are em...

ÐCommercially available alumina of 94% nominal purity was used to examine the in ̄uence of loading rate on toughening mechanisms. For ®ne-grained alumina, the crack resistance, KR, was found to be independent of crack length and loading rate. Coarse-grained alumina exhibited strongly rising R-curves where the initial fracture toughness, K0, was found to be independent of the loading rate. The ne...

Two-dimensional Finite Element Method simulations, which involve consideration of the nonlinearity of a material, have been conducted to gain understanding about the rigid-rigid polymer toughening concept we proposed. The simulation results for the plane stress condition indicate that as long as the inclusion phase possesses i) a 60% difference in the tangent modulus from that of the matrix at ...

Systematic studies of alloys based on TiCr, have been performed in order to impro Ttoughness of Laves phase intermetallics. The extent to which alloy compositions and annealing treatments influence the toughness was quantified by Vickers indentation. The single-phase Laves behavior was first established by studying stoichiometric and nonstoichiometric TiCr,. Next, alloying effects were investig...