Development of Cube-Textured Ni and Ni-W Alloy Tapes by Focused Infrared Heating

2006 ◽  
Vol 510-511 ◽  
pp. 258-261
Author(s):  
Jun Ki Chung ◽  
Sung Yeal Bae ◽  
Sung Gap Lee ◽  
Chan Park ◽  
Sang Im Yoo ◽  
...  
Keyword(s):  
Grain Size ◽  
Critical Role ◽  
Texture Development ◽  
Infrared Heating ◽  
Halogen Lamp ◽  
Ir Heating ◽  
Heat Treated ◽  
Steep Temperature Gradient ◽  
Infrared Heater ◽  
Cold Rolled

We fabricated bi-axially textured pure Ni and Ni–5at.%W (Ni-5W) alloy tapes for the application of rechargeable battery cathode and coated superconductor, where the controlled microstructure of the substrate plays a critical role. The sintered Ni or Ni-W rods were cold-rolled into the thin tapes of 80 ~ 100 µm thickness, and the tapes were heat-treated for texture development with a line focused infrared heater. The temperature was maintained at 800 ~ 1050 °C, using a 1kW double ended linear halogen lamp in 96%Ar-4%H2 atmosphere. The (2 0 0) texture of Ni tape was successfully formed through optimization of the recrystallization infrared heating condition for the cold rolled Ni tapes. The full width half maximum of the Ni tapes was less than 10o, and the grain size was 20 ~ 40 µm. Focused IR-heating resulted in a better texture development and smaller grain size compared to the conventional resistive heating because of the steep temperature gradient.

Texture Development in Cold Rolled and Annealed Ta

2011 ◽  
Vol 695 ◽  
pp. 153-157 ◽  
Author(s):  
Kuk Hyun Song ◽  
Han Sol Kim ◽  
Won Yong Kim
Keyword(s):  
Grain Size ◽  
Elevated Temperature ◽  
Annealing Temperature ◽  
High Vacuum ◽  
Surface Oxidation ◽  
Reduction Ratio ◽  
Texture Development ◽  
Fibre Texture ◽  
Annealed Material ◽  
Cold Rolled

In order to investigate the texture development in cold rolled and annealed tantalum (Ta), the present study was carried out. For this work, cold rolling was performed up to ~ 96% reduction in thickness, and annealing was performed at elevated temperature up to ~ 1200 °C for 60 min under the high vacuum to prevent the surface oxidation. As a result, increase in the reduction ratio of the cold rolled Ta was effective to develop the a fibre texture, with its texture components such as (001)<110> and (112)<110>. Also, resulting grain size was more refined by increase in reduction ratio, consequently, 96% cold rolled and annealed material showed the best refined grain size. However, in case of annealed material, g fibre texture with its texture component, such as (111)<121> and (111)<112>, was developed by increase in annealing temperature. In this study, we systematically discussed the texture development due to the increase in reduction ratio.

Grain Refinement in AZ91E Magnesium Alloy by Thermo-Mechanical Treatments

2005 ◽  
Vol 475-479 ◽  
pp. 493-496 ◽  
Author(s):  
Atsushi Yamamoto ◽  
Masahiko Ikeda ◽  
Harushige Tsubakino
Keyword(s):  
Grain Size ◽  
Magnesium Alloy ◽  
Grain Boundary ◽  
Grain Refinement ◽  
Mechanical Treatment ◽  
Fine Grained ◽  
Heat Treated ◽  
Cold Rolled ◽  
Thermo Mechanical Treatment ◽  
Hot Rolled

In order to improve poor formability in magnesium alloy, grain refinement has been attempted on AZ91E alloy by a thermo-mechanical treatment. Specimens were firstly cold-rolled at 10 %, then solution heat treated at 673 K for 86.4 ks, and hot-rolled at 573 K with about 5 % for four passes, or hot-rolled at 20 % with one pass. The rolled specimens were finally heat treated at 473 to 673 K for 3.6 to 36 ks. Microstructures in the starting material characterized by grain boundary precipitates and aluminum rich regions with about 180 µm in grain size were changed into fine grained microstructures with about 10 to 30 µm in diameter, in which precipitates of Mg17Al12 were uniformly distributed. Although the specimen was prepared by rolling, the (0001) texture was not so remarkable.

Effect of Shock Loading on the Microstructure of Uniloy 326

1974 ◽  
Vol 32 ◽  
pp. 504-505
Author(s):  
K. P. Staudhammer ◽  
L. E. Murr
Keyword(s):  
Grain Size ◽  
Shock Loading ◽  
Current Investigation ◽  
Two Phase ◽  
05 C ◽  
Shock Deformation ◽  
Heat Treated

The effect of shock loading on a variety of steels has been reviewed recently by Leslie. It is generally observed that significant changes in microstructure and microhardness are produced by explosive shock deformation. While the effect of shock loading on austenitic, ferritic, martensitic, and pearlitic structures has been investigated, there have been no systematic studies of the shock-loading of microduplex structures.In the current investigation, the shock-loading response of millrolled and heat-treated Uniloy 326 (thickness 60 mil) having a residual grain size of 1 to 2μ before shock loading was studied. Uniloy 326 is a two phase (microduplex) alloy consisting of 30% austenite (γ) in a ferrite (α) matrix; with the composition.3% Ti, 1% Mn, .6% Si,.05% C, 6% Ni, 26% Cr, balance Fe.

Slip traces caused by plastic deformation during recrystallization of thin metal sheets

1994 ◽  
Vol 52 ◽  
pp. 620-621
Author(s):  
H. Lin ◽  
D. P. Pope
Keyword(s):  
Grain Size ◽  
Grain Boundaries ◽  
Sample Thickness ◽  
List Type ◽  
Metal Sheets ◽  
Second Phases ◽  
Slip Traces ◽  
Series Of Experiments ◽  
Cold Rolled ◽  
Individual Grains

During a study of mechanical properties of recrystallized B-free Ni3Al single crystals, regularly spaced parallel traces within individual grains were discovered on the surfaces of thin recrystallized sheets, see Fig. 1. They appeared to be slip traces, but since we could not find similar observations in the literature, a series of experiments was performed to identify them. We will refer to them “traces”, because they contain some, if not all, of the properties of slip traces. A variety of techniques, including the Electron Backscattering Pattern (EBSP) method, was used to ascertain the composition, geometry, and crystallography of these traces. The effect of sample thickness on their formation was also investigated.In summary, these traces on the surface of recrystallized Ni3Al have the following properties:1.The chemistry and crystallographic orientation of the traces are the same as the bulk. No oxides or other second phases were observed.2.The traces are not grooves caused by thermal etching at previous locations of grain boundaries.3.The traces form after recrystallization (because the starting Ni3Al is a single crystal).4.For thicknesses between 50 μm and 720 μm, the density of the traces increases as the sample thickness decreases. Only one set of “protrusion-like” traces is visible in a given grain on the thicker samples, but multiple sets of “cliff-like” traces are visible on the thinner ones (See Fig. 1 and Fig. 2).5.They are linear and parallel to the traces of {111} planes on the surface, see Fig. 3.6.Some of the traces terminate within the interior of the grains, and the rest of them either terminate at or are continuous across grain boundaries. The portion of latter increases with decreasing thickness.7.The grain size decreases with decreasing thickness, the decrease is more pronounced when the grain size is comparable with the thickness, Fig. 4.8.Traces also formed during the recrystallization of cold-rolled polycrystalline Cu thin sheets, Fig. 5.

scholarly journals Influence of Post Weld Heat Treatment on the Grain Size, and Mechanical Properties of the Alloy-800H Rotary Friction Weld Joints

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4366
Author(s):  
Saqib Anwar ◽  
Ateekh Ur Rehman ◽  
Yusuf Usmani ◽  
Ali M. Al-Samhan
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Grain Size ◽  
Heat Affected Zone ◽  
Tensile Testing ◽  
Weld Zone ◽  
Alloy 800H ◽  
Weld Joints ◽  
Heat Treated ◽  
Friction Weld

This study evaluated the microstructure, grain size, and mechanical properties of the alloy 800H rotary friction welds in as-welded and post-weld heat-treated conditions. The standards for the alloy 800H not only specify the composition and mechanical properties but also the minimum grain sizes. This is because these alloys are mostly used in creep resisting applications. The dynamic recrystallization of the highly strained and plasticized material during friction welding resulted in the fine grain structure (20 ± 2 µm) in the weld zone. However, a small increase in grain size was observed in the heat-affected zone of the weldment with a slight decrease in hardness compared to the base metal. Post-weld solution heat treatment (PWHT) of the friction weld joints increased the grain size (42 ± 4 µm) in the weld zone. Both as-welded and post-weld solution heat-treated friction weld joints failed in the heat-affected zone during the room temperature tensile testing and showed a lower yield strength and ultimate tensile strength than the base metal. A fracture analysis of the failed tensile samples revealed ductile fracture features. However, in high-temperature tensile testing, post-weld solution heat-treated joints exhibited superior elongation and strength compared to the as-welded joints due to the increase in the grain size of the weld metal. It was demonstrated in this study that the minimum grain size requirement of the alloy 800H friction weld joints could be successfully met by PWHT with improved strength and elongation, especially at high temperatures.

Corrosion behavior of cold-rolled and post heat-treated 316L stainless steel in 0.9wt% NaCl solution

2021 ◽  
Vol 28 (3) ◽  
pp. 440-449
Author(s):  
K. Bin Tayyab ◽  
A. Farooq ◽  
A. Ahmed Alvi ◽  
A. Basit Nadeem ◽  
K. M. Deen
Keyword(s):  
Stainless Steel ◽  
Corrosion Behavior ◽  
316L Stainless Steel ◽  
Nacl Solution ◽  
Heat Treated ◽  
Cold Rolled

On the Nature of Grain Boundaries in Nanocrystalline Diamond

MRS Bulletin ◽  
1998 ◽  
Vol 23 (9) ◽  
pp. 36-41 ◽  
Author(s):  
P. Keblinski ◽  
D. Wolf ◽  
F. Cleri ◽  
S.R. Phillpot ◽  
H. Gleiter
Keyword(s):  
Grain Size ◽  
Grain Boundaries ◽  
Active Sites ◽  
Critical Role ◽  
Diamond Films ◽  
Structural Disorder ◽  
Nanocrystalline Diamond ◽  
High Wear Resistance ◽  
Atomic Structures ◽  
Nanocrystalline Diamond Films

The low-pressure synthesis of rather pure nanocrystalline diamond films from fullerene precursors suggests that for a small enough grain size the diamond structure may be energetically preferred over graphite. Because of the small grain size of typically about 15 nm in these films, a significant fraction of the carbon atoms is situated in the grain boundaries (GBs). The surprisingly high wear resistance of these films even after the substrate is removed and their high corrosion resistance suggest that the grains are strongly bonded. Grain-boundary carbon is also believed to be responsible for the absorption and scattering of light in these films, for their electrical conductivity, and for their electron-emission properties. In spite of all these indications of a critical role played by GB carbon in achieving the remarkable properties of nanocrystalline diamond films, to date the atomic structures of the GBs are essentially not known.It is well-known that the electronic and optical properties of polycrystalline silicon films are significantly affected by the presence of GBs. For example GBs can provide active sites for the recombination of electron-hole pairs in photovoltaic applications. Also, in electronic devices such as thin-film transistors, GBs are known to play an important role. Because of silicon's strong energetic preference for sp3 hybridization over other electronic configurations, the structural disorder in silicon GBs is accommodated by a distortion of the tetrahedral nearestneighbor bonds and in the extreme by the creation of dangling bonds—that is, of three-coordinated Si atoms each having one unsaturated, bound electron in an otherwise more or less tetrahedrally coordinated environment.

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