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In annealed samples it is found that the orientations of the new grains Introduction The deformation microstructure and texture of recrystallized grains of FCC metals with high stacking faulty energy (SFE) has been the subject of intense research for many years.
Specific interest has been given to studies of the Cube orientation-(001)[100], both on account of the practical importance of the development of cube orientation recrystallized grains during a number of commercial processing operations, and on account of the fact that rolling deformation of (001)[100] single crystals results in a distinctive macroscopic (sample scale) pattern of subdivision [4-7].
Annealing for 10 minutes at 350°C results in the formation of just a small number of recrystallizing grains.
The orientations of these grains, and of the surrounding remaining deformed material have been characterized also by EBSD line scans.
The line scan, indicated in the Fig.4a by the thick black line, goes through a few large recrystallized grains.

The grinding wheel manufacturer specifies the characteristic values (bounding type, grain size, grain material, hardness, etc.) which are only general information and do not represent the actual state of the grinding wheel during the process.
This method describes the grinding wheel topography by detecting the dynamic grains which act during the process.
During the grinding process, as the grains wear increases with time, the individual characteristics of the wheel also change, leading to different cutting edges and grain distributions on the grinding wheel.
Although specifications of the grinding tool, as hardness, grain type, grain size and bonding are indicated by the manufacturer, only a specific knowledge of the topography allows conclusions on the tools capability for the desired process [4].
The vertical axis represents the number of mapping points along the grinding wheel periphery during a complete revolution.

Hence, material removal is limited and the major action of the CBN grains is to reduce surface roughness through a burnishing action.
Slow feed rate corresponds to large number of spark-out passes and therefore reduces the roughness values.
θ equals half of the grain top angle, fa is the cross-feed rate and bs is the width of the wheel.
Using a grit distance derived from the static grain density is similar to using static grain number per unit area of wheel surface, which of course provides more grits and can derive much smaller chip thickness and thus lower roughness values.
A dynamic grain distance, l dd , can be derived from the active (dynamic) grain number [4], Nd, which is about 2-6% of static grain number, Ns.

The SPH technique is used in RADIOSS using a Lagrangian approach, which involves tracking the motion of a certain number of particles over time.
The FSPed specimen's grain size grows as the temperature rises, and Grain Boundaries (GBs) disappear.
This is due to the fact that bigger grains will form from smaller, previously shattered grains as the temperature rises.
HAZ has a large grain size compared to BM.
It is recommended to use a High-Performance Computer (HPC) with high number of cores and RAM to solve FSP models with SPH particles.

The results showed that the size of Si particles in Al-(1.44~12.4)Si-0.7Mg alloy sheets was approximately the same, but the number of Si particles increased as the Si content increased.
Therefore, the mixed grains phenomenon is alleviated.
On the other hand, the grain boundary movement is pinned by Si particles and the growth of grain is hindered [14,15].
This area stores a large amount of deformation energy, which enhance the growth of sub-grain with high angle grain boundary, and shrink the critical size of nucleation.
Moreover, the amount of Si particles increasing refines the grains of Al-xSi-0.7Mg alloy sheets in T4 temper, which as a result increases the quantity of grain boundaries.

A number of processes such as wire brushing (WB) [1-3], shot peening (SP) [4] and surface mechanical attrition treatment (SMAT) [5], have been studied towards modifying the surface grain structure of Mg sheet materials to improve their formability.
Some abnormal grain growth with an average grain size of 20 mm was also found adjacent to the refined layer.
Overall, a gradual grain size increase from surface towards mid-thickness was observed with mid-thickness grain size being quite close to the original annealed grain size (see Fig. 1(d)). 30 mm c 30 mm d 30 mm b 30 mm a Fig. 1.
They showed that wire brushing could cause ultrafine grains, leading to nano-sized grains on the brushed surface.
Also, owing to the non-basal texture of the WBA material and smaller grain size, slip could occur on several slip systems in fine-grained materials even at low strains [11].

Four factors, five level, central composite rotatable design matrix is used to optimize the number of experiments.
The formation of fine equiaxed grains in fusion zone increases the ultimate tensile strength of the welded joints.
The fine grains observed in the fusion zone may be responsible for higher tensile strength of the welded joints.
The grain coarsening deteriorates the ultimate tensile strength of these welded joints.
However one may consider more number of factors and their levels to improve the mathematical model.

Introduction The year 1969 saw a number of 'firsts' in the world of aerospace including the first flights of Boeing's 747, the Anglo-French Concorde and man's first landing on the moon.
By then, a number of significant 'firsts' had been discovered and developed including: 1.
The as cast and wrought microstructures were non-uniform and at 450 o C, much of the grain boundary restraining phase was solutionized, with the result that many grains were large.
Therefore, some other means of stabilizing the grains was needed.
A significant number of these have been and still are formed from SUPRAL 100/150.

The possibilities for grain refinement by post-processing are also restricted.
While the surface of pure magnesium is composed of separate or clustered single columnar grains, the surface of AZ91 is smooth and the single grains are grown together.
In contrast, after magnetron sputtering the pronounced columnar structure with a large number of separate single crystallites may lead to pore formation and of remaining open areas between the columnar grains is much higher.
The strong peak broadening indicates a small grain size and/or high stresses.
The target materials reveal the typical microstructure of conventional cast materials with a large number of precipitates, large variations in the concentration and also relatively large grain sizes.

The results showed that the USSP surface nanocrystallization could obtain the nanocrystalline grain.
But there are many factors that affect the corrosion resistance of nanocrystallization material, such as the character of alloying element, grain size, grain construction and so on.
The grain sizes were 26nm, 24.13 nm, 23.55 nm, 21.53 nm, 21.47 nm and 20.94 nm, respectively.
(1) The XRD was used to analyze the grain size of test face.
The USSP surface nanocrystallization could obtain the nano crystalline grain.