Grain Boundary Engineered Lead Alloys

ABSTRACTThe present work reports oii the effect of grain boundary structure on intergranular corrosion and creep by grain boundary diffusion in polycrystalline lead (Pb). “Special” boundaries characterized by low-Σ misorientations in the Coincident Site Lattice (CSL) model have been shown to exhibit resistance to grain boundary sliding and corrosion. PbCa and PbCaSn alloys having “special” grain boundary frequencies greater than 50% showed a 30 fold reduction in steady-state creep compared with corresponding as-received alloys containing 10% to 28% of low-Σ CSL boundaries in the microstructure of comparable grain size. At the same time, increasing the frequency of “special” boundaries enhanced alloy ductility with no compromize in tensile strength. Results from electrochemical corrosion tests on polarizied Pb alloys immersed in H2SO4 (S.G.=1.28) at 70°C indicate a clear correlation between the frequency of “special” boundaries and the prolifíeration of intergranular corrosion resulting in bulk weight loss from grain-dropping. Collectively, these results advocate adopting a “gram boundary design” approach in developing advanced lead-acid battery electrodes.

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Effect of Solid Solution Treatment on Corrosion Resistance of Al-Cu-Mg-Ag Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1032.213 ◽

2021 ◽

Vol 1032 ◽

pp. 213-219

Author(s):

Zhen Hua Cui ◽

Xiao Yan Liu ◽

Yan Qin Wang ◽

Hong Ru Yang ◽

Zhen Jie Cui ◽

...

Keyword(s):

Corrosion Resistance ◽

Grain Boundary ◽

Intergranular Corrosion ◽

Solution Treatment ◽

Electrochemical Corrosion ◽

Treatment Temperature ◽

Boundary Structure ◽

Solution Treatment Temperature ◽

Grain Boundary Structure ◽

Electrochemical Corrosion Resistance

In this experiment, Al-Cu-Mg-Ag alloy was used as material and solution temperature was used as variable to investigate its effect on the corrosion properties of the alloy and Hardness test, metallographic observation, electrochemical test, intergranular corrosion and exfoliation corrosion test were carried out on three groups of samples. The results show that the intergranular corrosion resistance of the alloy decreases with the increase of solution treatment temperature, and the sample treated at 505 °C has the best performance. This is mainly because grain boundary structure plays a role in increasing PFZ and expanding corrosion channels. The exfoliation corrosion resistance of Al-Cu-Mg-Ag alloy increases first and then decreases, and the sample treated at 515 °C has the best performance. This is due to the dual effects of grain boundary structure and grain morphology. On the one hand, the solution treatment temperature increases, which widens the precipitation-free zone and reduces the electrochemical corrosion resistance of the alloy. On the other hand, the increase of recrystallized grains decreases the cohesion of corrosion products and enhances the electrochemical corrosion resistance of the alloy.

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The Effect of Texture and Grain Boundary Structure on the Intergranular Corrosion of Stainless Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.157-162.1997 ◽

1994 ◽

Vol 157-162 ◽

pp. 1997-2004 ◽

Cited By ~ 5

Author(s):

Hyun Min Kim ◽

Jerzy A. Szpunar

Keyword(s):

Stainless Steel ◽

Grain Boundary ◽

Intergranular Corrosion ◽

Boundary Structure ◽

Grain Boundary Structure

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Grain Boundary Structure and Sliding of Alumina Bicrystals

MRS Proceedings ◽

10.1557/proc-601-125 ◽

1999 ◽

Vol 601 ◽

Cited By ~ 5

Author(s):

Y. Ikuhara ◽

T. Watanabe ◽

T. Yarnamoto ◽

T. Saito ◽

H. Yoshida ◽

...

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Small Angle ◽

Boundary Energy ◽

High Resolution Electron Microscopy ◽

Grain Boundary Sliding ◽

Boundary Structure ◽

Grain Boundary Energy ◽

Grain Boundary Structure ◽

Boundary Sliding

AbstractAlumina bicrystals were fabricated by a hot joining technique at 1500°C in air to obtain ten kinds of [0001] symmetric tilt grain boundaries which included small angle, CSL and high angle grain boundaries. Their grain boundary structures were investigated by high-resolution electron microscopy (HREM), and the respective grain boundary energies were systematically measured by a thermal grooving technique. It was found that grain boundary energy strongly depended on the grain boundary characters, e.g., there were large energy cusps at low Σ CSL grain boundaries. But, main part of grain boundary energy is likely to be due to the strain energy around the grain boundary, and the contribution of atomic configuration is not so large. Small angle grain boundaries were consisted of an array of partial dislocation with Burgers vector of 1/3[1100] to form the stacking faults between the dislocations. The behavior of grain boundary sliding was also investigated for typical grain boundaries by high-temperature creep test at 1400°C. As the result, the occurrence of grain boundary sliding was found to depend on the grain boundary atomic structure.

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Electromigration properties of multigrain aluminum thin film conductors as influenced by grain boundary structure

Journal of Materials Research ◽

10.1557/jmr.2001.0289 ◽

2001 ◽

Vol 16 (7) ◽

pp. 2124-2129 ◽

Cited By ~ 10

Author(s):

O. V. Kononenko ◽

V. N. Matveev ◽

D. P. Field

Keyword(s):

Grain Boundary ◽

Boundary Energy ◽

Boundary Structure ◽

Grain Boundary Character Distribution ◽

Direct Function ◽

Boundary Character ◽

Special Boundaries ◽

Grain Boundary Character ◽

Grain Boundary Structure ◽

Interconnect Lines

Electromigration rates in polycrystalline interconnect lines are controlled by grain-boundary diffusion. As such, reliability of such interconnects is a direct function of the grain-boundary character distribution in the lines. In the present work, drift velocity experiments were performed on multicrystalline lines of pure Al to determine the electromigration activation energy of the lines. Lines cut from films processed by partially ionized beam deposition techniques were analyzed. One set of lines was analyzed in the as-deposited condition while the other film was annealed before testing. The measured drift velocities varied dramatically between these two types of films, as did the grain-boundary character distributions measured by orientation imaging. The data were analyzed based on Borisov's equation to obtain mean grain-boundary energies. Grain-boundary energy of the film with poor electromigration performance was calculated to be that reported for random boundaries, while that for the more reliable film was calculated to be that reported for twin boundaries in Al. Percolation theory was used to aid explanation of the results based upon the fraction and connectedness of special boundaries in the films.

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Grain boundary structure observed by T.E.M

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109197 ◽

1978 ◽

Vol 36 (1) ◽

pp. 410-411

Author(s):

P.J. Goodhew

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Single Crystals ◽

Lower Energy ◽

Planar Defect ◽

Boundary Structure ◽

High Angle ◽

Thin Specimen ◽

Special Boundaries ◽

Grain Boundary Structure

This paper reports some observations on gold by TEM which imply that the dissociation of a high angle grain boundary into two lower energy boundaries may occur extensively.It is well established that grain boundaries of any desired geometry can be created in gold by the welding together of thin single crystals. The resultant thin bicrystal specimens are ideally suited for immediate examination by TEM and many aspects of grain boundary structure and behaviour in such specimens have been studied or discussed. One particularly useful specimen configuration can be achieved if the bicrystal is annealed until its boundary migrates (lowering its total area) until it is perpendicular to the surface of the thin specimen. This specimen geometry has been used to study, inter alia, the faceting of grain boundaries.During a study of the behaviour of coincidence high angle boundaries (i.e. those special boundaries whose geometry is such that a fraction 1/Σ of the lattice sites in both crystals coincide) it was noticed that the boundary under observation was no longer a single planar defect.

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Mechanical properties of nanocrystalline and epitaxial TiN films on (100) silicon

Journal of Materials Research ◽

10.1557/jmr.2001.0373 ◽

2001 ◽

Vol 16 (9) ◽

pp. 2733-2738 ◽

Cited By ~ 31

Author(s):

H. Wang ◽

A. Sharma ◽

A. Kvit ◽

Q. Wei ◽

X. Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Grain Boundary ◽

Single Crystal ◽

Grain Boundary Sliding ◽

Boundary Structure ◽

Triple Junctions ◽

Tin Films ◽

Grain Boundary Structure ◽

Transmission Electron

We investigated mechanical properties of TiN as a function of microstructure varying from nanocrystalline to single crystal TiN films deposited on (100) silicon substrates. By varying the substrate temperature from 25 to 700 °C during pulsed laser deposition, the microstructure of TiN films changed from nanocrystalline (having a uniform grain size of 8 nm) to a single crystal epitaxial film on the silicon (100) substrate. The microstructure and epitaxial nature of these films were investigated using x-ray diffraction and high-resolution transmission electron microscopy. Hardness measurements were made using nanoindentation techniques. The nanocrystalline TiN contained numerous triple junctions without any presence of amorphous regions. The width of the grain boundary remained constant at less than 1 nm as a function of boundary angle. Similarly the grain boundary structure did not change with grain size. The hardness of TiN films decreased with decreasing grain size. This behavior was modeled recently involving grain boundary sliding, which is particularly relevant in the case of hard materials such as TiN.

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The Influence of Grain Boundary Structure on Strain-Induced Grain Growth During Superplastic Deformation

MRS Proceedings ◽

10.1557/proc-196-21 ◽

1990 ◽

Vol 196 ◽

Cited By ~ 2

Author(s):

H. J. Frost ◽

R. Raj

Keyword(s):

Grain Boundary ◽

Grain Growth ◽

Superplastic Deformation ◽

Boundary Migration ◽

Forced Migration ◽

Grain Boundary Sliding ◽

Boundary Structure ◽

Grain Boundary Structure ◽

Diffusional Flow ◽

Boundary Sliding

ABSTRACTA model is presented to explain the grain growth that is often observed during superplastic deformation. The atomic structure of grain boundaries leads to a coupling between boundary sliding and boundary migration. There is a similar coupling between the absorption or emission of vacancies from a boundary and boundary migration. Because of these couplings, the grain boundary sliding and diffusional flow of superplastic deformation produce extensive boundary migration. We propose that this forced migration leads to random changes in the sizes of grains, and that this evolution of the grain size distribution leads to grain growth.

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Two Investigations into Grain Boundary Structure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080833 ◽

1977 ◽

Vol 35 ◽

pp. 688-691

Author(s):

P. Humble

Keyword(s):

Grain Boundary ◽

Dark Field ◽

Boundary Structure ◽

Boundary Dislocation ◽

Bright Field ◽

Intrinsic Structure ◽

Weak Beam ◽

Grain Boundary Structure ◽

Independent Information ◽

Diffraction Patterns

There has been sustained interest over the last few years into both the intrinsic (primary and secondary) structure of grain boundaries and the extrinsic structure e.g. the interaction of matrix dislocations with the boundary. Most of the investigations carried out by electron microscopy have involved only the use of information contained in the transmitted image (bright field, dark field, weak beam etc.). Whilst these imaging modes are appropriate to the cases of relatively coarse intrinsic or extrinsic grain boundary dislocation structures, it is apparent that in principle (and indeed in practice, e.g. (1)-(3)) the diffraction patterns from the boundary can give extra independent information about the fine scale periodic intrinsic structure of the boundary.In this paper I shall describe one investigation into each type of structure using the appropriate method of obtaining the necessary information which has been carried out recently at Tribophysics.

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Relationships Between Grain Boundary Structure and Material Properties

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001550 ◽

1980 ◽

Vol 38 ◽

pp. 366-369

Author(s):

Brian Ralph ◽

Barlow Claire ◽

Nicola Ecob

Keyword(s):

Grain Boundary ◽

Material Properties ◽

Main Property ◽

Grain Structure ◽

Boundary Structure ◽

Grain Boundary Structure ◽

Property Changes

This brief review seeks to summarize some of the main property changes which may be induced by altering the grain structure of materials. Where appropriate an interpretation is given of these changes in terms of current theories of grain boundary structure, and some examples from current studies are presented at the end of this paper.

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