This paper reports new data on the distribution of grain boundary planes in commercially available GBE copper. The results show that nearly 60% of grain boundary length was Σ3, i.e. annealing twin related. There was a slightly enhanced proportion of {111} boundary planes, even after Σ3 boundary segments were excluded from the data set. There was a high proportion of boundary plane length on the...

This work has two primary goals. The first is to advance our fundamental understanding of grain boundaries by making direct measurements of grain boundary thermodynamic properties using ultrafine-grained materials. The second is to explore possible deviations from conventional behavior at ultrafine grain sizes, specifically in regards to grain boundary thermodynamic properties and solute segreg...

Two-dimensional phase field simulations were performed of grain growth in highly textured materials with equal fractions of 2 texture components, denoted as α and β grains, and assuming 2 values of the grain boundary energies, namely σlow for the boundaries between grains of a different texture component and σhigh for boundaries between grains of a similar orientation, resulting in microstructu...

In the microcrystalline regime, the behavior of grain boundary-controlled electroceramics is well described by the “brick layer model” (BLM). In the nanocrystalline regime, however, grain boundary layers can represent a significant volume fraction of the overall microstructure and simple layer models are no longer valid. This work describes the development of a pixel-based finite-difference app...

The factors that govern cleavage cracking across high-angle grain boundaries are investigated theoretically. According to previous experimental observations, a cleavage front overcomes the resistance of a high-angle grain boundary by first penetrating across it at a number of break-through points (BTP) and then separating apart persistent grain-boundary islands (PGBI). In the current study, thi...

Microstructure evolution in thin Cu films during room temperature self-annealing is investigated by means of a mesoscale level set model. The model is formulated such that the relative, or collective, influence of anisotropic grain boundary energy, mobility and heterogeneously distributed stored energy can be investigated. Density functional theory (DFT) calculations are performed in the presen...

Olivine is the most important phase in the Earth’s upper mantle, where the bulk rock composition varies on average from lherzolitic to harzburgitic, where the olivine fractions are normally >60 %. Olivine is of major importance for Earth’s mantle dynamics and the presence of grain boundaries in olivine and their type might partially be responsible for attenuation phenomena as well as thermal an...

The preferred site of Mg segregation at = 11(113)grain boundaries in Al and the effects of Mg segregation on grain boundary cohesion have been investigated through first-principle pseudopotential total energy calculations. The results show that the Mg atom prefers to occupy the ‘looser’ site at the grain boundary of Al but not the ‘tighter’ site. Furthermore, on basis of the thermodynamic theor...

The jump condition at a possibly non-material interface for geometricallynecessary dislocation density in field dislocation mechanics (FDM) and its averaged approximation, phenomenological mesoscopic FDM (PMFDM), is derived. In the context of grain boundaries, the condition implies a tensorial constraint on all five grain boundary parameters, slip transmission at the boundary, possible grain bo...

In this paper we report the application of a five-parameter determination of grain boundary types to grain boundary engineered alpha-brass. The data are discussed particularly in terms of the distribution of boundary planes, and also with respect to the potential relationship between the planes distribution and the misorientation distribution. Approximately 20,000 grains comprised the total sam...