Grain Boundary Characteristics Optimization of 90Cu–10Ni Copper-Nickel Alloy for Improving Corrosion Resistance

The grain boundary character distribution and corrosion resistance of a 90% Cu 10% Ni alloy were investigated. When the rolling reduction was increased, the fraction of coincidence site lattice (CSL) grain boundaries with low-Σ index increased initially, and decreased thereafter. The highest fraction of low-Σ CSL boundaries (70%) was obtained through 9% secondary rolling reduction. Electrochemical testing indicated that the corrosion resistance improved significantly after intermediate deformation (7% and 9% reduction ratios) and high-temperature annealing. This improvement was attributed to an increase in the fraction of low-Σ CSL boundaries and the formation of triple junctions during recrystallization.

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Effect of Grain Boundary Characteristics on Lattice Orientations

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.26-28.1003 ◽

2007 ◽

Vol 26-28 ◽

pp. 1003-1006 ◽

Cited By ~ 1

Author(s):

Jae Hyung Cho

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Three Dimensional ◽

Microstructural Characterization ◽

Grain Boundary Character Distribution ◽

Average Scheme ◽

Plane Normal ◽

Grain Boundary Characteristics ◽

Correlation Parameters ◽

Boundary Characteristics

Grain boundary characteristics are defined by five parameter, grain boundary plane normal and misorientation angle/axis between two adjacent grains. The influence of the grain boundary character distribution on lattice evolution during deformation was investigated using three-dimensional crystal plasticity finite element method (CPFEM). Various combinations of grain boundaries were modeled systematically. In analyzing the numerical microstructural characterization obtained by the simulation, orientation average scheme and correlation parameters between misorientation and its special distribution are used. Inter- and intra-grain structures were investigated using the spatial distribution of lattice orientation. Main emphasis was placed on misorientation distributions around grain boundaries, where grain interaction mainly occurred.

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Grain Boundary Characteristics Evaluation by Atomistic Investigation Methods

MRS Proceedings ◽

10.1557/proc-1215-v16-24 ◽

2009 ◽

Vol 1215 ◽

Author(s):

Yoshiyuki Kaji ◽

Tomohito Tsuru ◽

Yoji Shibutani

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Density Functional ◽

Coincidence Site Lattice ◽

Individual Characteristics ◽

Material Strength ◽

Investigation Methods ◽

Grain Boundary Characteristics ◽

The Individual ◽

Boundary Characteristics

AbstractThe grain boundary has been recognized for one of the major defect structures in determining the material strength. It is increasingly important to understand the individual characteristics of various types of grain boundaries due to the recent advances in material miniaturization technique.In the present study three types of grain boundaries of coincidence site lattice (CSL), small angle (SA), and random types are considered as the representative example of grain boundaries. The grain boundary energies and atomic configurations of CSL are first evaluated by first-principle density functional theory (DFT) and the embedded atom method (EAM) calculations. SA and random grain boundaries are subsequently constructed by the same EAM and the fundamental characteristics are investigated by the discrete dislocation mechanics models and the Voronoi polyhedral computational geometric method. As the result, it is found that the local structures are well accorded with the previously reported high resolution-transmission electron microscope (HR-TEM) observations, and that stress distributions of CSL and SA grain boundaries are localized around the grain boundary core. The random grain boundary shows extremely heterogeneous core structures including a lot of pentagon-shaped Voronoi polyhedral resulting from the amorphous-like structure.

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Grain Boundary Characteristics and Stress-induced Damage Morphologies in Sputtered and Electroplated Copper Films

MRS Proceedings ◽

10.1557/proc-766-e2.3 ◽

2003 ◽

Vol 766 ◽

Author(s):

Hyun Park ◽

Soo-Jung Hwang ◽

Kyu Hwan Oh ◽

Young-Chang Joo

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Morphological Difference ◽

High Energy ◽

Triple Junctions ◽

Boundary Area ◽

Boundary Triple ◽

Surface Damages ◽

Grain Boundary Characteristics ◽

Boundary Characteristics

AbstractVarious Cu films were fabricated using sputtering and electroplating with and without additive, and their surface damages after annealing were investigated. After annealing at 435°C, the difference between damage morphologies of the films was observed. In some films stressinduced grooves along the grain boundaries were observed, while in the others voids at the grain boundary triple junctions were observed. It was also observed that the stress-induced groove was formed along the high energy grain boundaries. To explain the morphological difference of surface damages, a simple parameter considering the contributions of grain structures and grain boundary characteristics to surface and grain boundary diffusions is suggested. The effective grain boundary area, which is a function of grain size, film thickness and the fraction of high energy grain boundaries, played a key role in the morphological difference.

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