Stress and strain fields in a two-dimensional pixelwise disordered system are computed by a Fast Fourier Transform method. The system, a model for a ductile damaged medium, consists of an elastic-perfectly matrix containing void pixels. Its behavior is investigated under equibiaxial or shear loading. We monitor the evolution with loading of plastically deformed zones, and we exhibit a nucleatio...

Here we report novel phase-separation behavior accompanying mechanical fracture ("fracture phase separation"), which is observed in polymer solutions. Surprisingly, mechanical fracture becomes a dominant coarsening process of the phase separation. The transition from viscoelastic to fracture phase separation corresponds to the "ductile-to-brittle transition" in fracture of materials under shear...

We report a brittle Mg-based bulk metallic glass which approaches the ideal brittle behavior. However, a dimple structure is observed at the fracture surface by high resolution scanning electron microscopy, indicating some type of "ductile" fracture mechanism in this very brittle glass. We also show, from the available data, a clear correlation between the fracture toughness and plastic process...

The problem: A new type of steel is known as Twining Induced Plasticity Steel, more commonly known as TWIP Steel. There is a general interest in using this type of steel in the automotive industry due to its unique material properties such as super toughness and super ductility, although its chemical properties also play a vital role. It has a high content of Mn (more than 25%) and about 3% Si ...

Low strain hardening has hitherto been considered an intrinsic behavior for most nanocrystalline (NC) metals, due to their perceived inability to accumulate dislocations. In this Letter, we show strong strain hardening in NC nickel with a grain size of approximately 20 nm under large plastic strains. Contrary to common belief, we have observed significant dislocation accumulation in the grain i...

Related Articles The tensile strengths of heterogeneous interfaces: A comparison of static and dynamic first-principles calculations J. Chem. Phys. 135, 244706 (2011) Temperature-induced anomalous brittle-to-ductile transition of bulk metallic glasses Appl. Phys. Lett. 99, 241907 (2011) Size effects on the fatigue behavior of bulk metallic glasses J. Appl. Phys. 110, 113507 (2011) Mechanical re...

We report exceptional ductile behavior in individual double-walled and triple-walled carbon nanotubes at temperatures above 2000 degrees C, with tensile elongation of 190% and diameter reduction of 90%, during in situ tensile-loading experiments conducted inside a high-resolution transmission electron microscope. Concurrent atomic-scale microstructure observations reveal that the superelongatio...

This paper presents the results of an experimental study on the effect of limestone powder on the compressive strength, tensile behavior, and micromechanical parameters of a highly ductile cement composite incorporating limestone powder. Four mixtures were determined according to the replacement ratio of cement with limestone powder. A series of experiments including compressive strength, uniax...

This talk will discuss the relationships between subcritical crack growth and the nature of the loading, the environment under which the loading takes place and the type of material tested, and how this data is used in predictive analysis. Loading conditions will include sustained loading as well as constant and variable amplitude cyclic loading. The environments will include vacuum as a baseli...

Crustal scale fault zones extend below the brittle-ductile transition as ductile shear zones. Here we address question of which regime, brittle or ductile, initiates and controls overall system localization. Observations crustal but low displacement conjugate strike-slip faults show that they are typically nearly orthogonal, expected from plastic criteria. Sub-crustal faults, however, have acut...