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Although certain limitations exist, the LUMet technique offers a very reliable characterization platform with a number of potential applications in metallurgical process engineering.
Grain size measurements.
Results and Discussion Austenite Grain Growth.
This temperature region is often associated to the occurrence of abnormal grain growth with a wide grain size distribution leading to a strong contribution to attenuation coming from a small number of large grains.
At the grain coarsening temperature, the laser ultrasonic grain size was overestimating the average size of the structure.

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].

Experimental Procedures Workpiece materials and grain structures.
The milling tool used in this study was carbide cutter which diameter of the end mill was 12 mm and number of tungsten carbide inserts in the cutter was 4.
In experiment, we found that the length of chip became shorter as the grain size of specimen increases, which may be attributed to heterogeneous deformation in specimen with coarse grains.
The grain shapes in specimens with large grains such as specimen 1# and 2# are branch-like or dendrite, whereas the grain shapes in specimens with fine grains such as 5# and 6# are globular, which can be seen in figure 3.
The increase of strength of materials will increase cutting force, but the key point of questions is that what extent of grain refining can bring rising to cutting force, which is needed deeper research works. 1 2 3 4 5 6 0 200 400 600 800 1000 1200(a) Milling force,* Specimen number Main milling force Radial milling force 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 0 200 400 600 800 1000 1200 1400(b) Main milling force Radial milling force Milling force,* Average grain size,mm Fig. 2 The relationship between milling force with grain size of specimen (a) The testing results of main milling force and radial force (b) The variation of main milling force and radial milling force with grain size of specimen Fig. 3 Microstructure in as-cast workpieces of Inconel 718C (a) lengthened dendrite in specimen 1# (b) uniform equiaxed grains in specimen 5# In order to understand the relationship between the grain size and cutting force,

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.

Grain growth is the coarsening process in which curvature-driven motion of grain boundaries leads to elimination of grains and increasing average grain size.
The anecdotal nature of the demonstration in Fig. 2 needs to be extended to statistically significant numbers of occurrences of each of the phenomena mentioned as well as to other materials.
These numbers translate to 1.2 x 106 voxels in the current data to as many as 3 x 107 voxels.
While optimized meshes can reduce these numbers by using larger voxels in regions of uniform orientation, the numbers are still daunting for finite element and other modeling efforts.
This work was supported in part by the Metals and Nano-Structures program of the National Science Foundation under award number DMR-0805100 and in part by the MRSEC program of the National Science Foundation under Award Number DMR-0520425.

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.

The built tool can operate real-time and fine-grained monitoring.
In other words, they offer coarse-grained network monitoring.
Then reading kernel data in Proc Interface module, Kernel module can get all open port numbers and the corresponding inode numbers.
At this point, from the correspondence of specified process inode numbers with system-open port inode numbers, we can get the correspondence of specified process with port numbers.
It verifies that the software achieves real-time online as well as fine-grained network monitoring.

Comparison between the growth behaviour of the small Goss grains and that of the large matrix grains in silicon steels.
The growth of a given grain depends on the evolution of its surrounding grain boundaries and not the average evolution of the whole matrix, the mean parameters of the matrix can hide the effect of the real neighbourhood for a grain located in a textured cluster.
-a- -b- -c- Fig.4: Spatial distribution of grains with orientation A (-a-), orientation (-b-) and other orientations (-c-) Figure 4 shows the spatial distribution of grains A, grains B and random grains corresponding to {200} pole figures of the figure 3.
It can be confirmed that the grains A form clusters, whereas the distribution of the other grains is more homogeneous.
A site is not characterized by an orientation number, but by a triplet (φ1, φ, φ2) in the Euler orientation space, the grain orientations are not random.

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.

Grain boundary diffusion in the ultrafine-grained Ni is found to be significantly faster than in the coarse-grained Ni, which indicates a 'non-equilibrium' (deformation-modified) state of grain boundaries in the former.
Introduction To date, a number of various techniques of severe plastic deformation (SPD) has been developed [1], and equal-channel angular pressing (ECAP) worked out by Segal [2] is one of the most widely used.
In a number of studies it was demonstrated that non-equilibrium boundaries are characterized by enhanced energy, excess free volume and accelerated diffusion [5]-[7].
On the other hand, the non-equilibrium boundaries are the ultra-fast diffusion paths, as shown in a number of studies [13]-[16].
Micro-strains in Ni versus the number of passes by DCAP and ECAP We found that SPD processing via both methods increases the level of micro-strains by a factor of 2.5, and a noticeable growth of the micro-strains is observed only up to 2 passes.