Dendrite Growth Morphology in the Supercooled Melts of Copper and Copper Alloys

The technique of paper-supported copper electrodeposition provides examples of well-presented fractal and dense radial structures. The growths may be developed to reveal concentration gradients around the growths at low cell overpotential. Measurements for current and length scale against time, within a mid-range of cell overpotentials, fit an ohmic model of the growth conditions. To examine the relation of growth morphology to the micrometre-scale structure, we grew first at one overpotential and then continued at a lower overpotential. Electron microscope observations of this growth reveal a distinct change in microstructure from irregular to dentritic microcrystalline from the high to low potential respectively. The interface between the growths is a distinctive compact granular deposit. The granular deposit is unstable to branching and dendrite growth.

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Dendrite Growth Morphology Modeling in Liquid and Solid Electrolytes

10.2172/1659759 ◽

2020 ◽

Author(s):

Yue Qi ◽

Long-Qing Chen ◽

Xingcheng Xiao ◽

Qinglin Zhang Zhang

Keyword(s):

Solid Electrolytes ◽

Dendrite Growth ◽

Growth Morphology

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Morphology and atomic structure of segregated grain boundaries in Cu-Sb

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121673 ◽

1992 ◽

Vol 50 (1) ◽

pp. 254-255

Author(s):

R. W. Fonda ◽

D. E. Luzzi

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Intergranular Fracture ◽

Atomic Structure ◽

Copper Alloys ◽

Polycrystalline Materials ◽

Grain Boundary Embrittlement ◽

Boundary Embrittlement

The properties of polycrystalline materials are strongly dependant upon the strength of internal boundaries. Segregation of solute to the grain boundaries can adversely affect this strength. In copper alloys, segregation of either bismuth or antimony to the grain boundary will embrittle the alloy by facilitating intergranular fracture. Very small quantities of bismuth in copper have long been known to cause severe grain boundary embrittlement of the alloy. The effect of antimony is much less pronounced and is observed primarily at lower temperatures. Even though moderate amounts of antimony are fully soluble in copper, concentrations down to 0.14% can cause grain boundary embrittlement.

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TEM study of a biofilm on copper corrosion

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163563 ◽

1996 ◽

Vol 54 ◽

pp. 220-221

Author(s):

W. A. Chiou ◽

N. Kohyama ◽

B. Little ◽

P. Wagner ◽

M. Meshii

Keyword(s):

Marine Bacterium ◽

Culture Medium ◽

Copper Alloys ◽

Pure Copper ◽

Localized Corrosion ◽

Natural Seawater ◽

Copper Corrosion ◽

New Approach ◽

The Past ◽

Copper Tolerant

The corrosion of copper and copper alloys in a marine environment is of great concern because of their widespread use in heat exchangers and steam condensers in which natural seawater is the coolant. It has become increasingly evident that microorganisms play an important role in the corrosion of a number of metals and alloys under a variety of environments. For the past 15 years the use of SEM has proven to be useful in studying biofilms and spatial relationships between bacteria and localized corrosion of metals. Little information, however, has been obtained using TEM capitalizing on its higher spacial resolution and the transmission observation of interfaces. The research presented herein is the first step of this new approach in studying the corrosion with biological influence in pure copper.Commercially produced copper (Cu, 99%) foils of approximately 120 μm thick exposed to a copper-tolerant marine bacterium, Oceanospirillum, and an abiotic culture medium were subsampled (1 cm × 1 cm) for this study along with unexposed control samples.

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