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The Effects of Different Abrasive Grain Sizes of Diamond Wheel on Grinding-induced Surface Damage.
a (grain size:60#) b (grain size:80#) c (grain size:60#) d (grain size:80#) Fig. 2 Grinding surface topographies of FCC under different abrasive grain sizes of wheel In Fig. 2(a) and 2(c), the abrasive grain sizes are 60#, by contrast, in Fig. 2(b) and 2(d), the abrasive grain sizes are 80#.
Consequently, the grinding surface topographies, under the abrasive grain size of 80#, are better than which are under the abrasive grain size of 60#.
The major reason is that the abrasive grain is smaller and finer with the abrasive grain size numbers increasing, as a result, the wear scars are shallower and denser.
With the increase of abrasive grain sizes number of diamond wheel, the surface damage is better and better.

Since creep resistance is influenced by the grain size, it increases due to the fine-grained structure as a result of recrystallization during extrusion.
Grains near precipitations show even smaller grain sizes (< 10 µm).
Number of cycles to fracture reaches the ones of WE43 between stress amplitudes of 120 and 140 MPa.
Using S-N data of AZ31 -1- all the RE containing alloys show significantly lower number of cycles to fracture.
Mg10Gd1Nd at 130 MPa reached cycle numbers between 72,000 and 130,000, see Fig. 4c.

Hence it became a necessity to modify their structure and refine their grains.
ECAP autographic records, for ZA22 grain refined by Ti.
ECAP autographic records for ZA22 grain refined by Ti-B.
Hence reducing the number of stages required for forming them at high strain beyond the plastic instability and all its investigated micro alloys.
Packwood: The Grain Refinement of Zinc-Aluminum Alloys by Titanium Can.

As the number of ECAP passes was increased, the applied strain was accumulated in the samples as calculated in Table 1.
A fine-grained material is harder and stronger than one that is coarse grained, since a fine-grained material has a greater total grain boundary area to impede dislocation motion [4].
Hardness and strain stored in the specimens as a function of number of ECAP pass.
No Number of ECAP pass Hardness (Hv) Strain 1. 0 44.9 0 2. 2 99.4 0.67 Referring from Fig.2, ageing heat treatment at 1 hour shows that ECAPed specimen has higher hardness than that of raw (cast) specimen, this is probably caused by the grains of ECAPed specimen are relatively smaller (Fig.4).
The accumulated strain leads to directional grain orientation and grain refinement. 2.

In addition, a number of elastomers are available acting as a fuel.
These problems were more evident in slender grains.
There are at least two thin wires placed in specific sections of grain.
The grain is then ignited to be burnt one dimensionally.
Figure 2: Wiring pattern in a grain section.

This observation should be attributed to the addition of grain refiner C2Cl6.
It is worth noting that the grain size of the AM60 alloy is reduced by almost two times in the C2Cl6 treated specimen due to the grain refinement effect of the C2Cl6 addition to the alloy.
With the addition of the C2Cl6 powders, the number of nuclei and nucleation rate increases.
Average grain sizes of AM60 and C2Cl6 treated AM60.
The melting temperature of the AM60 alloy was also reduced by the grain refiner.

Abstract: Recrystallization of rolled Zr single crystals is considered in comparison with analogous recrystallization processes in rolled coarse-grained iodide Zr.
Fig. 3 shows reorientations of prismatic axes {1120} due to recrystallization in the rolled Zr single crystal (a) and of the coarse-grained iodide Zr (b), both rolled by ~80%.
Hence, twinned crystallites are characterized with low strain hardening and contain relatively small numbers of recrystallization nuclei, growing at the expense of neighbors.
Namely here, grains are localized, deformed by participation of two or three different slip systems, i.e. prismatic, basal and pyramidal ones [3].
The greatest number of recrystallization nuclei forms in α-Zr grains plastically deformed by operation of different slip systems, as in crystallites corresponding to stable orientations of the rolling texture.

The average grain size is close to 30µm (Figure 1).
Figure 4 : SMT–induced microstructure in the ultrafine grain region.
Grains are equiaxed with an average size of 300-500 nm.
The wear volume is plotted as a function of the number of sliding cycle on figure 6.
Right – wear volume as a function of the number of sliding cycles.

This image includes qualitatively the crystalline information between polycrystalline grains.
This analysis technique includes the processing of statistical data of grain size and orientations.
The size of a- or b-axis oriented grains are relatively small, compared to c-axis oriented grains, which are imaged in Fig. 1 (b) by blue color as indicated by 1, 2, and 3 numbers in Fig 1 (b), and which are also localized in larger area than other grains. θ-2θ x-ray scans were performed to compare the nanoscopic orientations of Fig. 1 with macroscopic polycrystalline orientations (Fig. 2 ) of BLT films on Pt electrodes.
Ferroelectric domains of c-axis orientated grains, which are indicated by 1, 2, and 3 numbers in Fig. 4 (a) and (b), respectively, show no changes in the phase image as shown in Fig. 4 (b), even after applied voltage of 10V.
C-axis oriented grains with plate-like morphology show almost linear dielectric behavior.

Again a similar microstructure was obtained when the B2O3 content was raised to 1 mol% except the number of abnormally grown grains was increased.
The 2mol% B2O3 addition resulted in a sudden grain growth with large pores trapped among the grains.
The fine-grained matrix attached on the large grain surfaces within the pore cavities can be clearly seen in Fig1c.
This phase can be seen as dark grains in the backscattered electron image given in Fig.1f, which arises from the lighter atomic number contrast of this Ti-rich phase compared to the matrix grains.
The addition of B2O3 above 0.5 mol% increases the grain size.