Search results

The orientation numbers between 1 and Q are randomly assigned to each lattice site of the microstructure.
Si denotes one of the Q possible grain orientations number at site i.
Sj represents the orientation number of site j which is the neighbor of site i.
The above steps are repeated until the desired evolution step number is reached.
The orientation number Q of lattice sites for matrix phase ranges from 1 to 200.

Compared with the high heating rate treatment, the slow one apparently leads to significantly smaller Al3Zr dispersoids, the dimension of the dispersoids decreases from 35 nm to 22 nm, and the number density of Al3Zr particle in the center of the grains increases from 13/μm2 to 35/μm2.
A large number of non-equilibrium constituent phases are present along primary α-Al grain boundaries in the ingot.
These Al3Zr particles are to stabilize the grain structure of the alloy and prevent recrystallization after hot deformation by pinning grain and subgrain boundaries [7].
There are no dispersoids precipitated adjacent to the grain boundary in two nearby grains, while in the other grain the Al3Zr particles are dispersly distributed.
Thus, a larger number of dispersoids can be formed by holding at 400°C.

A structure of layers (flat grains) is observed.
The thickness of separate layers depends on the number of passes, and it is in the range of 150 to 400nm.
As the number of passes increased, the increase of the density of the poles <112> || ND and <110> || ED was observed.
The microstructure and texture evolution in the deformed and recrystallized states were investigated by TEM orientation mapping in a number of samples deformed in 6 passes.
The diameter of the recrystallized grains in the vicinity of LSPPs was only occasionally larger than the average grain size.

Hence, the process consists of a large number of alternating deformations and dwell steps.
In addition, due to the large number of cycles, the modeling results, especially the prediction of grain size, can easily be affected by uncertainties in the input data.
Ring rolling, in contrast, is an incremental forming process in which the ring is progressively shaped in a number of revolutions.
Each point in the ring undergoes a number of deformation cycles with interpass times of variable duration in-between.
During this grains coarsened considerably (cf.

Tang et al. [7-10] studied the process of fine grain cast and the heat treatment of fine grain casting wheels.
The calculation shows the grain size of conventional casting sample is ASTM M10-M7 level while the grain size of Microcast-X fine grain casting is ASTM 5-3 level (＜100μm).
The behavior of rupture seems to be positive-break caused by positive stress, while a large number of dimples and two-phase particle occurred in separation surface, indicating the mechanism of rupture to be trans-granular ductile fracture caused by the segregation of microporous.
Firstly, the grain size is refined and dispersion of grains size is decreased (refer to Fig. 1 A~C.
Conclusion 1) Specimen with grain size less than 100μm was achieved by Microcast-X fine grain casting. 2) Microcast-X fine grain casting refines grain and dendrite significantly, and could reduces the segregation of Al, Ti and Ta.

Their room temperature tensile properties were examined and compared to those of coarse grained counterpart.
Introduction The advent of innovative severe plastic deformation (SPD) techniques makes the grain size of metallic materials be easily refined to the submicrometer level, so-called ultrafine grained (UFG) materials.
UFG materials are quite attractive due to their ultrahigh strength, more than twice of the coarse grained counterparts.
Both ferrite grain size and martensite island size were ~1.3 µm and the martensite volume fraction was about 28 %.
The microstructure of the ECAPed low carbon steel is characterized by UFG ferrite grains with a high density of lattice dislocations, subdivided pearlite colonies, and a large number of low- and high-angle boundaries with extrinsic boundary dislocation, etc [8].

The total number of grains of 5 grain boundary in whole mapping is 8869 with I AGG grain.
Number of grains included in misorientation calculation seems to be enough to obtain statistics.
Typical and reliable equipment obtaining orientation information is Transmission Electron Microscope(TEM), of which reasonably and practically measurable number of grains is below one hundred.
EBSD mapping and Montage technique used in this study can increase the measurable grain number of statistical data about hundred thousand, which is thousand times larger than TEM.
Large number of captured grain inside AGG grain has high angle boundary of 90°.

The results show the hardness increased in the first turn of HPT and further increased with increasing numbers of turns.
The total numbers of rotations were ¼, ½, ¾, 1, 2 and 5.
Similarly, the Si particle size decreased as the number of HPT turns increased, as shown in Fig.2.
Second, the hardness increases with the number of HPT turns.
It is apparent that both the YS and the UTS increase as the number of HPT turns is increased.

Accordingly, in order to distinguish the three types of grains in three-phase microstructure, just assume the total number of order parameters is p.
Only (p-2) number of order parameters is evolved during simulation to represent the matrix grains.
The Modified Three-dimensional Simulation Algorithm In some former works, a large number of order parameters are involved to avoid coalescence of grains during evolution.
Kill and Chen [13] proposed a way called reassignment algorithm to reduce the number of order parameters without coalescence of grains.
Computer simulation of the domain dynamics of a quenched system with a large number of nonconserved order parameters: The grain-growth kinetics, Phys.

In a recent paper [2], the evolution of the microstructure during recovery and recrystallisation was investigated in a number of high-temperature homogenized, hot- and heavily cold-rolled AA3103 samples.
Grains that are much larger than the average grain size appear in the non-homogenized material right after heating to 300ºC (see Figs.2,3).
Fig. 3 Diameter of the largest grain D in the sampled area versus the mean grain size dm.
Since there is no increase in the total number of particles, the solute is precipitated at already existing particles and a coarsening takes place.
Whether grain growth is discontinuous or continuous depends on the original grain size, as indicated.