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Grain growth was observed to occur at 250°C in the FC condition of Al 6016 after 12 passes of ECAE where the average grain size approached 1µm.
Bright Field (BF) TEM micrographs were taken and the grain size and aspect ratio were determined after measuring at least 50 grains at each temperature.
At 250°C grain instability and subsequent grain growth was observed, Fig. 3b.
The hardness of Al 6016 was also monitored as a function of static annealing temperature and found to depend on the number of passes of ECAE up until grain instability was observed at 250°C.
Grain growth was observed to occur at 250°C in the FC condition of Al 6016 after 12 passes of ECAE where the average grain size approached 1µm.

Grain Size Sensitivity Modeling and Analysis.
Fig.1 Grain contact model of lapping (uneven grain) A contact model of lapping is show in Fig.1.
The number and size of active grains in the work field are created according to Fig.2 by a randomizer.
(b) the number and size of active grain in the work field are generated by a randomizer.
Typical grain size distribution Fig.3.

With increasing cyclic number, the mean stress max min( ) / 2 mσ σ σ= + decreases sharply from 50MPa to about 10MPa after 1000 cycles.
Grain boundaries with large angle have formed between grain A and grain D, as well as between grain B and grain C.
While in the case between grain C and grain D, coalescence of subgrain boundaries is proceeding.
At the same time, the dislocation boundaries of grain C and grain D is migrating outward.
Generally, the driving force for further grain growth decreases with recovery proceeding in grain interior.

Grain Refinement of Phosphorus Deoxidised Copper M.J.
Similar to grain refinement of pure Al [18], grain refinement of pure Cu requires a combination of inoculation and grain growth restriction effects to yield to a fine equiaxed grain structure [13].
Increasing the cooling rate produced a finer grain structure, but with regions having columnar grains.
Briefly, effective grain refinement requires not only the nucleating particles to be potent, efficient, sufficient in number, well dispersed, of suitable particles size and size distribution, but even solidification under high undercooling conditions.
This indicated that nano-sized MgO particles could act as potent heterogeneous nucleation sites in Cu, however there were not enough number of those particles to effectively prevent coarse grain growth. 2.

Nevertheless achieving a high percentage of superplasticity in magnesium alloys is reported by a number of different authors.
Superplasticity in magnesium alloys can be achieved by either coarse or fine grains.
Superplastic materials generally have grain sizes in the range of 3–5µm.
Fine grained superplasticity normally requires that grain size should be homogeneously distributed on the entire surface and below 10 – 15 µm without significant growth during deformation.
Sensitiveness of SPF towards Strain Rate By observing large number of superplastic deformation data it is confirmed that the strain rate is given by: where C is a constant, E is the elastic modulus, Doexp(-Q/RT) is the appropriate diffusion coefficient, Q is the activation energy, R is the gas constant, T is the absolute temperature, b is the Burgers vector, d is the grain size and p is the grain size exponent, n is the stress exponent and σ is the stress [51].

Research and design on Aesthetics of Wood Grain Li Xu1, a , Dagang Li2,b* , Changyan Xu3,c,Zhaoyang Xu4,c 1,2,3College of Wood Science & Technology, Nanjing Forestry University, Nanjing, Jiangsu Province, 210037,P.R.China axuli7992@163.com,b njfuldg@163.com, cchangyanxu1999@yahoo.cn,dhughxzy@hotmail.com Keywords: Wood grain, Pattern, Aesthetics, Research, Design Abstract: From the study on the status of wood aesthetics, firstly through analyzing the macro grain of wood in three sections, the article indicates people’s aesthetic demand that the wood's natural grain meets the visual and psychological need of people.
And then, it studies the wood microstructure by the principle of form beauty which makes deeper discussion of the wood’s microstructure grain on aesthetic form.
Besides the difference in the number and size of axial parenchyma cells on the sides of pores, there exist other differences in the depth and the thickness of wood rays.
Rhythm and Cadence Rhythm from the language of music, refers to the laws of sound movement priorities, and a reflection of the proportion of the number sequence.
The microstructure of the wood determines its macro-grain, consumers need to understand the microstructure of the species while selecting the macro- grain of the floor, and in this way, consumers can be more at ease.

Austenite grains were observed by optical microscope and grain size was measured by using the average linear intercept method.
As the temperature exceeds 1350℃, grains suddenly grow up and average grain size approaches to 40.3μm.
There are large number of nanometer particles in steel holding for 2s at 1200℃, however, these second-phase particles can hardly be seen in steel after holding for 2s at 1350℃.
So the number of TiN particles gradually decreases and average size of TiN gradually increases as temperature increment and time extension.
Summary (1) Austenite grains grow slowly as peak temperature is lower than 1250℃.As the temperature exceeds 1350℃, grains suddenly grow up and average grain size attains to 40.3μm

The extensive abnormal grain growth can be obtained by the exclusive growth of a few grains over the remaining matrix grains in the presence of grain growth inhibitors such as precipitates.
Since the HAADF image is formed from incoherently-scattered electrons collected and exhibits contrast dependent on the average atomic number (Z) [5,6], the contrast difference between the precipitates and grain boundaries in HAADF images is clearer than that in conventional bright-field (BF) transmission electron microscopy (CTEM) images.
In our samples, abnormal grain growth occurred above 900°C.
The area and number of precipitates were measured using a digitized image analyzer (Scion Image for Windows).
Figure 1(e) shows the triple junction of grain boundaries with precipitates and grain boundaries with many precipitates.

The process can be repeated a number of times in the same set-up [88].
It is clear that the processing temperature has a more important role in grain refinement than the number of passes.
Further passes brought similar morphological changes: with an odd number of passes, the grains were severely elongated along in a direction Inclined at 30° to the longitudinal axis and the grains were restored to an equiaxed shape with the subsequent even number of passes [121].
The tensile strength increases with increasing number of passes of ECAP.
Fig. 19 XRD results of grain size and micro-strain vs. number of revolutions in HPT [169].

Firstly, Mg deforms by a limited number of slip and twin systems and secondly Mg develops strong textures during processing [1].
Twinning is highly sensitive to grain size [2], with finer grain sized samples exhibiting a lower volume fraction of twins.
There have been a number of studies that aim to reduce the grain size of magnesium below the values produced by conventional processing.
After hot rolling, a number of annealing treatments were carried between 150°C and 350°C.
This resulted in a grain size of 2.2µm, Figure. 2b.