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The grain size hardly changed during drying.
However, although the number of pores decreased when annealed at 240 o C, the size of pores increased when annealed at 170 or 240 o C.
As indicated in Figs. 4(b) and 4(c), whilst the number density of pores dropped, the pores became significantly large.
Normal grain growth was identified when annealed at 170 or 200 oC.
On the contrary, when annealed at 240 oC, abnormal grain growth with sufficiently large grain size was observed to occur, although macropores still resided therein.

In order to obtain the diffractions from an enough number of grains, various types of oscillation methods, which were translation, rotation and tilting of the specimen, were examined.
The number of the grains, N, existing the radiation area, A, in the measurement of laboratory X-rays is given by 29767== S A N where d is 37 µm and A is 4×8 mm2.
As mentioned above, the luck of the number of diffracted grains is most likely the reason for these results.
With tilting oscillation, the number of diffracted grains does not increase much, but the diffracted grains change because the tilting oscillation can shift the normal vector from diffraction plane.
The solid squares, triangles and circles correspond to the translation distances of 1, 2 and 4 mm, and to the number of grains of 5322, 7182 and 10903, respectively.

Fabrication and Cutting Performance of Ultrafine Grain Composite Diamond Coated Drills Y.P.
The wear of drills is evaluated by the number of holes machined successfully and the cutting length.
The grains are relatively large; the average size is about 6µm.
Broadening of the diamond band is a result of the decrease in grain size and phase purity.
(a) Uncoated drill ;(b) microcrystalline diamond; (c) ultrafine grain/microcrystalline diamond.

But the surface roughness of the specimens with large grains are 1.4 to 4 times higher than that of the specimens with small grains.
The averaged grain size is about 30ìm and 150ìm.
Grain morphology change with the applied strain.
For the crystal C as the increase of strain the twin numbers are increased.
As the roughness increases there are two mutational points in the large grain whereas it is continuously change in the small grain.

The billets were obtained from commercially available coarse-grained, hot-extruded rod and fine-grained, hot-rolled plate.
Fine-grained samples were successfully processed at 200 °C, while coarse-grained ones must have been heated up to 250 °C to avoid fracture.
The initial microstructure of the rod was heterogeneous with coarse grains (~80 µm) surrounded by colonies of small grains (~10 µm), as shown in Fig. 1a.
However, in some cases, fracture occurred before reaching the intended number of passes.
Part of this research was supported by the Engineering and Physical Sciences Research Council [grant number EP/G03477X/1].

The control of grain boundaries (GBs) is the key to improve the efficiency and production yield.
The atomic number of Fe (26) is nearly two times larger than that of Si (14), which would give rise to higher brightness in ADF images.
Large residual strain inside grains acts as the driving force for the formation of SA-GBs.
In most commercial mc-Si wafers, the grains are not grown in large size due to non-optimized growth condition.
Thus, sub-grains and SA-GBs possess both strong electrical activity and large strain.

The acetification restrains the increase of grain size for CaO as the number of cycles increase.
The grain size of CaO derived from original and modified limestones with the number of cycles can be determined from the main peak breadth in the XRD spectra.
The grain size of CaO derived from both original and modified limestones increases with the number of cycles.
It can be seen that the grain size of CaO derived from original limestone increases more rapidly than modified one with the number of cycles.
And the grain size of CaO derived from modified limestone increases more slowly than original one with the number of cycles increase.

The alloying of B or Ni to Cr reduces the grain size of the alloys.
terms of grain size effect.
The estimated volume fraction of grain boundaries increases from 3 vol% for 100 nm of the grain size to 30 vol% for 10 nm of the grain size.
The microhardness of Cr or Ti based alloys shows the maximum around 50at% elements, where the number of bonding of Cr or Ti and elements becomes maximum.
The microhardness of nanostructured Cr based alloys are controlled by the grain size, and also the structure of grain boundaries such as amorphous structure.

Fig. 2 Schematic of marked grain boundaries (TD is parallel to horizon) Figs. 3 show the measured results of angle of grain boundaries with increasing local strain.
The twinned bands are usually surrounded in grains and all twinned bands end at grain boundaries.
In this zone the twinning occurred very early and the twinned band number 2 is the first one.
The number 6 is a grain boundary which is a turning joint and a target to suffer collision of twinning bands.
Grain boundary turning is an apparent characterisation of crystal grain turning, the later is an essential mechanism for plastic deformation process in magnesium alloy; the grain boundaries turn to parallel loading direction. 2.

As the number of MAF pass increases the average grain size was reduced because of plastic deformation by plane strain condition.
The strength was also increased as the number of passes increased [13].
As the number of passes increases the silicon particle reduced their size from dendrite structure [10].
More number of grain boundaries interact with the external force which restricts the movements of dislocations by entanglement with other dislocations and grain boundaries this may be the other reason for the increase in hardness value.
Number of MDF Pass Grain size (μm) UTS Hardness (VHN) Compression Strength(MPa) (MPa) 1 As-received 90 120 55 315 2 1 46 150 69 390 3 2 22 159 76 435 4 3 9 171 81 495 Fractography Figure 5 shows the fracture surface as (a), (b), (c) and (d).