scholarly journals Forming Mechanism of High-Speed Cold Roll Beating of Spline Tooth

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Ting Niu ◽  
Yong-Tang Li ◽  
Zhi-Qi Liu ◽  
Hui-Ping Qi
Keyword(s):  
Process Parameters ◽  
High Speed ◽  
Room Temperature ◽  
Electron Backscatter Diffraction ◽  
Forming Mechanism ◽  
Grain Sizes ◽  
Cold Roll ◽  
Subgrain Rotation ◽  
Electron Backscatter ◽  
Backscatter Diffraction

The spline tooth of ASTM 1045 was fabricated by high-speed cold roll-beating (HSCRB) process at room temperature. Microhardness of the spline tooth was examined by a nanoindenter. The grains and misorientation angle distributions were measured by electron backscatter diffraction (EBSD). The results showed that the microhardness was improved up to 1280 μm deep from the surface of the spine tooth. The microhardness and the grain sizes gradually decreased in the direction away from the surface. On the surface, the fraction of ultrafine grains increased up to about 90%, and the average grain diameter (which was ∼0.56 µm) decreased by 71.4%. The model of grain evolution during HSCRB process is proposed in this work. New grains appear first on the boundaries of the elongated grains within numerous subgrains. The elongated grains are refined as a result of subgrain rotation. By analyzing the HSCRB technical principle, we concluded that the process parameters affect the refinement degree of studied steel by determining beating pass, beating pass interval time, and strain rate.

Influence of Temperature upon the Texture Evolution and Mechanical Behaviour of Zircaloy-4

2011 ◽  
Vol 702-703 ◽  
pp. 834-837
Author(s):  
Peter Honniball ◽  
Michael Preuss ◽  
Joao Quinta da Fonseca
Keyword(s):  
Mechanical Behaviour ◽  
Room Temperature ◽  
Electron Backscatter Diffraction ◽  
Texture Evolution ◽  
Crystal Plasticity Finite Element ◽  
Ebsd Data ◽  
Electron Backscatter ◽  
Different Temperatures ◽  
Increasing Temperature ◽  
Backscatter Diffraction

The mechanical behaviour and texture evolution during uniaxial compression of Zircaloy-4 at different temperatures (25, 300, 500 C) has been studied. At room temperature and 300 C the texture evolution and strain-hardening behaviour observed are attributed to the activation of {10-12} tensile twinning, which can be identified in optical micrographs and electron backscatter diffraction (EBSD) data. The influence of twinning upon the texture evolution and hardening rate becomes less apparent with increasing temperature. Nevertheless twinning is still active at 500 C. Simulation of the texture evolution at 500 C using crystal plasticity finite element modelling (CPFEM) indicates that slip alone cannot explain the experimentally observed textures at this temperature.

Nanoindentation and Microstructural Study of Cu-Co Alloys after Severe Plastic Deformation

2013 ◽  
Vol 592-593 ◽  
pp. 720-723 ◽  
Author(s):  
Jiří Buršík ◽  
Petr Král ◽  
Milan Svoboda ◽  
Jiří Dvořák ◽  
Václav Sklenička
Keyword(s):  
Mechanical Properties ◽  
Electron Microscope ◽  
Room Temperature ◽  
Electron Backscatter Diffraction ◽  
Microstructural Study ◽  
Angular Pressing ◽  
Electron Backscatter ◽  
Backscatter Diffraction ◽  
Co Alloys ◽  
Scanning Electron

In this work we studied the microstructure evolution due to equal channel angular pressing of Cu-2wt.%Co alloy after various heat treatments. Several subsequent passes were performed at room temperature. The microstructure was characterized using electron backscatter diffraction technique in a scanning electron microscope. Local mechanical properties were studied by means of nanoindentation experiments using a Hysitron PI85 picoindenter operated inside an electron microscope.

Strain-Induced Selective Growth in 1.5% Temper-Rolled Fe∼1%Si

2011 ◽  
Vol 17 (3) ◽  
pp. 362-367 ◽  
Author(s):  
Tricia A. Bennett ◽  
Peter N. Kalu ◽  
Anthony D. Rollett
Keyword(s):  
Electron Backscatter Diffraction ◽  
Selective Growth ◽  
Stored Energy ◽  
Grain Sizes ◽  
Geometrically Necessary Dislocation ◽  
Electron Backscatter ◽  
Ebsd Technique ◽  
Backscatter Diffraction ◽  
Dislocation Content

AbstractStrain-induced selective growth was investigated in a 1.5% temper-rolled Fe∼1%Si alloy using the electron backscatter diffraction (EBSD) technique. The EBSD technique was used to quantify the presence of orientation spreads within grains and to show that this particular case of selective growth can be directly related to differences in stored energy as reflected in the geometrically necessary dislocation content. The differences in stored energy were sufficient to give rise to selective growth as evidenced by bi-modal grain sizes.

Determination of the orientation relationship between austenite and 5M modulated martensite in Ni–Mn–Ga alloys

2011 ◽  
Vol 44 (6) ◽  
pp. 1222-1226 ◽  
Author(s):  
Zongbin Li ◽  
Yudong Zhang ◽  
Claude Esling ◽  
Xiang Zhao ◽  
Liang Zuo
Keyword(s):  
Orientation Relationship ◽  
Room Temperature ◽  
Electron Backscatter Diffraction ◽  
Residual Austenite ◽  
Orientation Data ◽  
Correct Orientation ◽  
Electron Backscatter ◽  
Crystallographic Characteristics ◽  
Backscatter Diffraction

The microstructural and crystallographic characteristics of 5M martensite in an Ni50Mn28Ga22alloy were investigated by electron backscatter diffraction (EBSD) analysis. The microstructure of 5M martensite observed at room temperature can be characterized by broad plates with alternately distributed fine lamellae (variants). With the accurate EBSD orientation measurements and by application of monoclinic superstructure information, four twin-related variants in one broad plate were identified. On the basis of the correct orientation data of martensite variants acquired from the EBSD measurements, the more favourable orientation relationship between austenite and 5M martensite was revealed to be the Pitsch relation with (101)A//(1 {\overline 2} \hskip1{\overline 5})5Mand [10 {\overline 1}]A//[{\overline 5} \hskip1 {\overline 5} 1]5Mby detailed crystallographic calculation without residual austenite.

Using Electron Backscatter Diffraction (EBSD) to Measure Misorientation between ‘Parent’ and ‘Daughter’ Grains. Implications for Recrystallisation and Nucleation

2004 ◽  
Vol 467-470 ◽  
pp. 573-578 ◽  
Author(s):  
Angela Halfpenny ◽  
David J. Prior ◽  
John Wheeler
Keyword(s):  
Crystallographic Orientation ◽  
Electron Backscatter Diffraction ◽  
Mantle Structure ◽  
Boundary Misorientation ◽  
Original Parent ◽  
Subgrain Rotation ◽  
Electron Backscatter ◽  
Orientation Information ◽  
Backscatter Diffraction

Electron backscatter diffraction (EBSD) is an extremely valuable tool, as it measures full crystallographic orientation information. This technique has been used to measure the statistics of misorientations between original ‘parent’ grains and recrystallised ‘daughter’ grains in a mylonitic quartzite. The angle of misorientation has implications on the controlling recrystallisation mechanism. The sample is a natural mylonitic quartzite collected from the stack of Glencoul, NW Scotland. The sample exhibits a common partially recrystallised microstructure. The data shows the average misorientations between the ‘parent’ and ‘daughter’ grains are 30º, this value seems too high for only subgrain rotation recrystallisation to be taking place. Moreover there is no gradation in the boundary misorientation from the internal substructure of the ‘parent’ grain to the ‘daughter’ grains. The internal substructure size of the ‘parent’ grain is bigger than the size of the ‘daughter’ grains. For subgrain rotation recrystallisation you may expect to see a core and mantle structure and for the ‘daughter’ grains’ to be of similar size to the internal substructure of the ‘parent’ grain. Another mechanism has either controlled the recrystallisation altogether or has become active after subgrain rotation had taken place and modified the microstructure.

Dynamic Recrystallisation of Quartz

2004 ◽  
Vol 467-470 ◽  
pp. 1243-1250 ◽  
Author(s):  
John Wheeler ◽  
Zhenting Jiang ◽  
David J. Prior ◽  
Jan Tullis
Keyword(s):  
Driving Force ◽  
Strain Energy ◽  
Electron Backscatter Diffraction ◽  
Dislocation Creep ◽  
High Angle ◽  
Subgrain Rotation ◽  
Electron Backscatter ◽  
Dynamic Recrystallisation ◽  
Plastic Strain Energy ◽  
Backscatter Diffraction

It is generally agreed that the driving force (plastic strain energy) is much too small to allow "classical" nucleation during static and dynamic recrystallisation, and that rotation/growth of subgrains is an alternative. The latter explanation predicts that new grains should begin at low angles to old grains. We have used electron backscatter diffraction on an experimentally deformed quartz polycrystal that has deformed by dislocation creep and partially recrystallised. In a region shortened by about 30% new grains are at high angles (much greater than 15º) to adjacent parent grains. A histogram of misorientation versus number of boundaries shows a gap at 15-20º. In its simple form we expect the subgrain rotation model to predict a spectrum of misorientations but with most of them being low angle. Instead, the histogram suggests that new boundaries began life as high-angle structures, so current models for deformation-induced nucleation require refinement.

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