Development of Growth Texture in Nanocrystalline Fe-Ni Alloys

2005 ◽  
Vol 495-497 ◽  
pp. 749-754 ◽  
Author(s):  
Chang Sik Ha ◽  
Yong Bum Park
Keyword(s):  
Energy Density ◽  
Grain Growth ◽  
Fibre Type ◽  
Texture Evolution ◽  
Orientation Dependence ◽  
Texture Development ◽  
Fibre Texture ◽  
Abnormal Growth ◽  
Ni Alloys ◽  
Texture Change

In electroformed pure Ni and Fe-Ni alloys with nanometer-sized crystallites, grain growth that takes place during annealing results in a common texture change. With regard to the macrotextures, the as-deposited textures were of fibre-type characterized by strong <100>//ND and weak <111>//ND components, and the texture development due to grain growth was defined by strong <111>//ND fibre texture with the minor <100>//ND components. It was clarified by means of the microtexture analysis that abnormal growth of the <111>//ND grains occurs in the early stages of grain growth. The possible effects of the abnormal grain growth on the texture evolution have been discussed in terms of the orientation dependence of energy density.

Textures and Grain Growth in Nanocrystalline Fe-Ni Alloys

2005 ◽  
Vol 475-479 ◽  
pp. 3483-3488 ◽  
Author(s):  
J.H. Seo ◽  
Jong Kweon Kim ◽  
T.H. Yim ◽  
Yong Bum Park
Keyword(s):  
Energy Density ◽  
Grain Growth ◽  
Fibre Type ◽  
Texture Evolution ◽  
Orientation Imaging Microscopy ◽  
Orientation Dependence ◽  
Coarse Grained ◽  
Abnormal Growth ◽  
Ni Alloys ◽  
Orientation Imaging

The texture evolution due to grain growth that takes place during annealing was investigated in nanocrystalline Fe-Ni alloys fabricated by using a continuous electroforming method. In the current materials, grain growth occurred during annealing at much lower temperatures than in conventional coarse-grained counterparts. With regard to the macrotextures, the as-deposited textures were of fibre-type characterized by strong <100>//ND and weak <111>//ND components, and the occurrence of grain growth resulted in the strong development of the <111>//ND fibre texture with the minor <100>//ND components. It was clarified using orientation imaging microscopy that abnormal growth of the <111>//ND grains in the early stages of grain growth plays an important role on the texture evolution. The origin of the abnormal grain growth has been discussed in terms of the orientation dependence of energy density.

Grain Growth and Texture Development in Nanostructured Invar Alloy

2004 ◽  
Vol 467-470 ◽  
pp. 1313-1318 ◽  
Author(s):  
Jong Kweon Kim ◽  
Jun Hyuk Seo ◽  
Yong Bum Park
Keyword(s):  
Grain Growth ◽  
Texture Evolution ◽  
Orientation Imaging Microscopy ◽  
Orientation Dependence ◽  
Invar Alloy ◽  
Abnormal Growth ◽  
Orientation Imaging ◽  
Invar Alloys ◽  
Low Thermal Expansion ◽  
Texture Change

In the present work, a nanocrystalline Invar alloy (Fe-36wt%Ni) foil was fabricated by using a continuous electroforming method. This material exhibited outstanding mechanical properties and a relatively low thermal expansion coefficient as compared to conventional Invar alloys. The as-deposited texture was of fibre-type characterized by strong <100>//ND and weak <111>//ND components. Grain growth occurred during annealing beyond 350°C and resulted in such texture change that the <111>//ND fibre texture strongly developed with the minor <100>//ND components. It was clarified using orientation imaging microscopy that abnormal growth of the <111>//ND grains in the early stages of grain growth plays an important role on the texture evolution. The mechanism of the abnormal grain growth has been discussed in terms of the orientation dependence of energy density.

Abnormal Grain Growth during Annealing in Nanocrystalline Fe-Ni Alloys

2007 ◽  
Vol 558-559 ◽  
pp. 1279-1282 ◽  
Author(s):  
J.H. Seo ◽  
Jong Kweon Kim ◽  
Yong Bum Park
Keyword(s):  
Grain Growth ◽  
Fibre Type ◽  
Texture Evolution ◽  
Orientation Imaging Microscopy ◽  
Abnormal Grain Growth ◽  
Morphological Features ◽  
Ni Alloys ◽  
Early Stages ◽  
Orientation Imaging

The texture evolution due to grain growth that takes place during annealing was investigated in nanocrystalline Fe-Ni alloys fabricated by using an electroforming method. In the current materials, the as-deposited textures were of fibre-type characterized by strong <100>//ND and weak <111>//ND components, and the occurrence of grain growth during annealing resulted in the strong development of the <111>//ND components with a significant decrease of the <100>//ND components. It was clarified that abnormal grain growth plays an important role on the evolution of the microstructures and textures. The abnormally grown grains were observed using orientation imaging microscopy in the early stages of grain growth, and their morphological features have been discussed.

Control of Microstructures and Textures in Nanocrystalline Fe-50wt%Ni Foil

2007 ◽  
Vol 124-126 ◽  
pp. 1181-1184 ◽  
Author(s):  
Jong Kweon Kim ◽  
Shi Hoon Choi ◽  
Yong Bum Park
Keyword(s):  
Mechanical Properties ◽  
Grain Growth ◽  
Rapid Growth ◽  
Texture Evolution ◽  
Texture Development ◽  
Annealed Specimen ◽  
Electrodeposition Method ◽  
Texture Change ◽  
Ni Alloy

The texture development and the mechanical properties were investigated in a nanocrystalline Fe-50wt%Ni alloy fabricated by using an electrodeposition method. The as-deposited texture was characterized by a mixture of major <100>//ND and minor <111>//ND fibre components. Grain growth occurred in the specimen during annealing above 410oC, and resulted in the texture change that the <111>//ND fibre component developed strongly with decreasing <100>//ND fibre component. This texture evolution was attributed to the abnormally rapid growth of the <111>//ND grains, which became much coarser than the <100>//ND and other oriented grains in the fully annealed specimen.

Texture of Electrodeposited Nanocrystalline Ni-Fe with Banded Structure

2011 ◽  
Vol 702-703 ◽  
pp. 912-915
Author(s):  
Uta Klement ◽  
Mehrdad Shahabi-Navid ◽  
Glenn D. Hibbard
Keyword(s):  
Optical Microscopy ◽  
Grain Growth ◽  
Cross Section ◽  
Growth Direction ◽  
Texture Development ◽  
Banded Structure ◽  
Fibre Texture ◽  
Annealing Temperatures ◽  
Orientation Maps ◽  
Final Fibre

Optical microscopy on the etched cross-section of a nanocrystalline Ni-18 wt.% Fe electrodeposit revealed the existence of a banded structure perpendicular to the growth direction. To evaluate if the banded structure is affecting grain growth and texture development, EBSD orientation maps were obtained after annealing for 30 min at 300, 350, and 400°C. Grown grains were found to be random in shape and no preferential sites for grain growth were observed. The texture of the grown grains is changing upon annealing and the final fibre texture parallel to growth direction of the electrodeposit can be obtained from texture components found at lower annealing temperatures when performing one or two consecutive twinning operations.

Texture Development in Pure Mg and Mg Alloy AZ31

2005 ◽  
Vol 495-497 ◽  
pp. 623-632 ◽  
Author(s):  
Günter Gottstein ◽  
T. Al Samman
Keyword(s):  
Static Recrystallization ◽  
Texture Evolution ◽  
Texture Development ◽  
Mg Alloy ◽  
High Temperature Deformation ◽  
Temperature Deformation ◽  
Alloy Az31 ◽  
The Poor ◽  
Texture Change ◽  
Similar Texture

Texture evolution in pure Mg and Mg alloy AZ31 during deformation and annealing was investigated. The poor low temperature ductility can be attributed to both, insufficient shear systems and unfavorable deformation geometry. Static recrystallization was shown to proceed discontinuously despite little texture change. High temperature deformation was accompanied by dynamic recrystallization with similar texture development as during static recrystallization.

scholarly journals Texture and Structure Evolution During Indirect Extrusion of an AlSiMgMn Aluminium Alloy

1997 ◽  
Vol 30 (1-2) ◽  
pp. 81-95 ◽  
Author(s):  
Hans Erik Vatne ◽  
Ketill Pedersen ◽  
Otto Lohne ◽  
Gaute Jenssen
Keyword(s):  
Aluminium Alloy ◽  
Texture Evolution ◽  
Strong Dependence ◽  
Extrusion Temperature ◽  
Texture Development ◽  
Structure Evolution ◽  
Fibre Texture

Texture evolution during indirect extrusion of cylindrical profiles of an AlSiMgMn aluminium alloy was investigated in the present work. The effect of extrusion temperature on texture development, through-thickness texture variations and texture variations along the length of the extruded profiles were investigated. In all cases a combined 〈100〉 and 〈111〉 fibre texture developed. Generally, the 〈111〉 fibre was sharper than the 〈100〉 fibre. The texture evolution was rather similar along the length of the profile, while the variations through the thickness were considerable. In a region midways between the centre and the surface of the profiles, the 〈100〉 fibre was weakened, and in the surface regions the two fibres were significantly rotated. The texture measurements showed a strong dependence on extrusion temperature, in the sense that the higher the temperature, the sharper the 〈100〉 fibre texture. The influence of texture variations on formability were also investigated.

The Orientation Dependence of Strain Hardening and Texture Development in an Extruded Magnesium Alloy

2014 ◽  
Vol 783-786 ◽  
pp. 363-368 ◽  
Author(s):  
D. Sarker ◽  
Dao Lun Chen
Keyword(s):  
Magnesium Alloy ◽  
Strain Hardening ◽  
Texture Evolution ◽  
Extrusion Direction ◽  
Orientation Dependence ◽  
Mechanical Anisotropy ◽  
Hardening Behavior ◽  
Compression Direction ◽  
Texture Change ◽  
Strain Hardening Behavior

Extruded magnesium alloys showed mechanical anisotropy due to the development of strong crystallographic textures during forming processes. In the present study the strain hardening behavior and texture evolution of an extruded AM30 magnesium alloy were studied in compression using cylindrical samples oriented at angles of 0°, 15°, 30°, 45° and 90° from the extrusion direction (ED). The yield strength decreased with increasing angle up to 45° and then increased at 90° from the ED, while the ultimate compressive strength exhibited a reverse trend. Both hardening capacity and fracture strain first increased from 0° to 45° and then decreased at 90° from the ED. The strain hardening behavior was directly related to the texture change and twinning, which played a key role in accommodating the compressive deformation, as the c-axes in most grains were observed to rotate always towards the anti-compression direction, irrespective of the sample orientation.

Effect of Micro-Elasticity on Grain Growth and Texture Evolution: A Phase Field Study

2010 ◽  
Vol 654-656 ◽  
pp. 1590-1593 ◽  
Author(s):  
Dong Uk Kim ◽  
Seong Gyoon Kim ◽  
Won Tae Kim ◽  
Jae Hyung Cho ◽  
Heung Nam Han ◽  
...  
Keyword(s):  
Energy Density ◽  
Grain Growth ◽  
Phase Field ◽  
Strain Energy Density ◽  
Strain Energy ◽  
Elastic Anisotropy ◽  
Texture Evolution ◽  
Fiber Texture ◽  
Abnormal Grain Growth ◽  
Elastic Load

In this presentation, a novel phase field grain growth model combined with a micro-elasticity effect including elastic anisotropy and inhomogeity is presented to demonstrate the effect of micro-elasticity on grain growth and texture evolution. We report on texture evolution and abnormal grain growth induced by external elastic load from the viewpoint of micro-elasticity and first demonstrate that the previous mechanism (macroscopic viewpoint) on the effect of external elastic load on grain growth does not work in strain-controlled system. In contrast to the macro-elastic descriptions, strong localization of strain energy density and inhomogeneous distribution even inside grains are observed. Moreover, elastically soft grains with a higher strain energy density grow at the expense of the elastically hard grains to reduce the total strain energy. It is observed that strong <100>//ND fiber texture was developed in poly-crystalline Cu with initial random texture by biaxial external strain while <111>//ND fiber texture evolved in biaxial external stress condition. Even, grain growth of <100>//ND textured grains is occurred as abnormal grain growth when <100>//ND textured grains are surrounded by <111>//ND fiber textured grains.

scholarly journals Mean Field Analysis of Orientation Selective Grain Growth Driven By Interface-Energy Anisotropy

1994 ◽  
Vol 343 ◽  
Author(s):  
J. A. Floro ◽  
C. V. Thompson
Keyword(s):  
Grain Size ◽  
Size Distribution ◽  
Grain Growth ◽  
Texture Evolution ◽  
Mean Field ◽  
Orientation Distribution ◽  
Interface Energy ◽  
Abnormal Grain Growth ◽  
Field Analysis ◽  
Energy Anisotropy

ABSTRACTAbnormal grain growth is characterized by the lack of a steady state grain size distribution. In extreme cases the size distribution becomes transiently bimodal, with a few grains growing much larger than the average size. This is known as secondary grain growth. In polycrystalline thin films, the surface energy γs and film/substrate interfacial energy γi vary with grain orientation, providing an orientation-selective driving force that can lead to abnormal grain growth. We employ a mean field analysis that incorporates the effect of interface energy anisotropy to predict the evolution of the grain size/orientation distribution. While abnormal grain growth and texture evolution always result when interface energy anisotropy is present, whether secondary grain growth occurs will depend sensitively on the details of the orientation dependence of γi.

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