scholarly journals Progressive changes in crystallographic textures of biominerals generate functionally graded ceramics

2022 ◽  
Author(s):  
David Wallis ◽  
Joe Harris ◽  
Corinna F Böhm ◽  
Di Wang ◽  
Pablo Zavattieri ◽  
...  
Keyword(s):  
Structural Materials ◽  
Functionally Graded ◽  
Single Crystalline

Biomineralizing organisms are widely praised for their ability to generate structural materials with exceptional crystallographic control. While earlier studies highlighted near-to single-crystalline biominerals, complex polycrystalline features are more widespread yet...

scholarly journals MIT-ONR Workshop Covers Functionally Graded Structural Materials

MRS Bulletin ◽  
1995 ◽  
Vol 20 (1) ◽  
pp. 54-55
Author(s):  
S. Suresh ◽  
A. Mortenson ◽  
H. Mcmanus
Keyword(s):  
Structural Materials ◽  
Functionally Graded

Characteristics of Functionally Graded Bimetallic Aluminium Alloys by Sequential Casting Technique

2015 ◽  
Vol 830-831 ◽  
pp. 383-386 ◽  
Author(s):  
Akhil S. Karun ◽  
Hari Sanil ◽  
T.P.D. Rajan ◽  
Uma Thanu Subramonia Pillai ◽  
B.C. Pai
Keyword(s):  
Functionally Graded Materials ◽  
Aluminium Alloys ◽  
Functional Performance ◽  
Cast Alloy ◽  
Structural Materials ◽  
Functionally Graded ◽  
Effect Of Temperature ◽  
Graded Materials ◽  
Casting Technique ◽  
Alloy Cast

Light weight aluminium alloys and low-density materials have drawn the attention of researchers as potential structural materials for transportation sector due to the requirement of effective reduction in fuel consumption, stringent emission norms and higher payload capacity. Functionally Graded Materials (FGM) provides variation in properties and better functional performance within a component. Sequential casting is fairly a new technique to produce functionally graded materials and components by controlled mould filling process. Bimetallics of aluminium alloys are prepared by sequential casting using A390-A319 alloy (cast-cast alloy) and A390-A6061 alloy (cast-wrought alloy) combination and solidified under gravity. The effect of temperature of the two melts and gap between pouring of the melts on microstructure and properties of the bimetals are investigated. The microstructures show good interface bonding between the two different alloy metals. The hardness testing shows higher hardness at hypereutectic alloy region. The process described in this study shows potential and effective approach to create good bonding between two different aluminium alloys to develop advanced functional and structural materials which can be used in various automobile components to reduce the overall weight of the vehicle, by which better fuel efficiency and performance can be achieved.

“Preparation of Single Crystalline Gold Films for ED Studies”

1972 ◽  
Vol 30 ◽  
pp. 634-635
Author(s):  
Joseph D. C. Peng
Keyword(s):  
Crystal Morphology ◽  
Diffraction Theory ◽  
Scattering Matrix ◽  
Vacuum Evaporation ◽  
Gold Films ◽  
Matrix Formulation ◽  
Silver Films ◽  
Single Crystalline ◽  
Grating Pattern ◽  
Stacking Disorder

The relative intensities of the ED spots in a cross-grating pattern can be calculated using N-beam electron diffraction theory. The scattering matrix formulation of N-beam ED theory has been previously applied to imperfect microcrystals of gold containing stacking disorder (coherent twinning) in the (111) crystal plane. In the present experiment an effort has been made to grow single-crystalline, defect-free (111) gold films of a uniform and accurately know thickness using vacuum evaporation techniques. These represent stringent conditions to be met experimentally; however, if a meaningful comparison is to be made between theory and experiment, these factors must be carefully controlled. It is well-known that crystal morphology, perfection, and orientation each have pronounced effects on relative intensities in single crystals.The double evaporation method first suggested by Pashley was employed with some modifications. Oriented silver films of a thickness of about 1500Å were first grown by vacuum evaporation on freshly cleaved mica, with the substrate temperature at 285° C during evaporation with the deposition rate at 500-800Å/sec.

Recombination Characteristics of Single-Crystalline Silicon Wafers with a Damaged Near-Surface Layer

2013 ◽  
Vol 58 (2) ◽  
pp. 142-150 ◽  
Author(s):  
A.V. Sachenko ◽  
◽  
V.P. Kostylev ◽  
V.G. Litovchenko ◽  
V.G. Popov ◽  
...  
Keyword(s):  
Surface Layer ◽  
Crystalline Silicon ◽  
Silicon Wafers ◽  
Single Crystalline Silicon ◽  
Near Surface ◽  
Single Crystalline

Synthesis of Jumbo-size Single Crystalline Bi$lt;inf$gt;2$lt;/inf$gt;Se$lt;inf$gt;3$lt;/inf$gt; Nanoplates and Nanoribbons by Vapor Transportation

2014 ◽  
Vol 29 (11) ◽  
pp. 1199
Author(s):  
LI Xiao-Shuai ◽  
WANG Zeng-Mei ◽  
ZHU Ming-Fang ◽  
WANG Shan-Peng ◽  
TAO Xu-Tang ◽  
...  
Keyword(s):  
Single Crystalline

Formation of Large, Orientation-Controlled, Nearly Single Crystalline Si Thin Films on SiO2 Using Contact Printing of Rolled and Annealed Nickel Tapes

2003 ◽  
Vol 762 ◽  
Author(s):  
Hwang Huh ◽  
Jung H. Shin
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
High Resolution ◽  
Amorphous Silicon ◽  
Tem Analysis ◽  
Contact Printing ◽  
Single Crystalline ◽  
High Resolution Tem ◽  
Lateral Crystallization ◽  
Si Films

AbstractAmorphous silicon (a-Si) films prepared on oxidized silicon wafer were crystallized to a highly textured form using contact printing of rolled and annealed nickel tapes. Crystallization was achieved by first annealing the a-Si film in contact with patterned Ni tape at 600°C for 20 min in a flowing forming gas (90 % N2, 10 % H2) environment, then removing the Ni tape and further annealing the a-Si film in vacuum for2hrsat600°C. An array of crystalline regions with diameters of up to 20 μm could be formed. Electron microscopy indicates that the regions are essentially single-crystalline except for the presence of twins and/or type A-B formations, and that all regions have the same orientation in all 3 directions even when separated by more than hundreds of microns. High resolution TEM analysis shows that formation of such orientation-controlled, nearly single crystalline regions is due to formation of nearly single crystalline NiSi2 under the point of contact, which then acts as the template for silicide-induced lateral crystallization. Furthermore, the orientation relationship between Si grains and Ni tape is observed to be Si (110) || Ni (001)

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