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Grain Refinement Grain refinement as well as refinement of primary particles such as Si is a well-known effect of ultrasonic processing.
There are a number of mechanisms suggested to explain the refining effect of ultrasonic cavitation that are reviewed elsewhere [3, 4].
On decreasing the temperature below the formation temperature of Al3Zr (e.g. 720–740 °C, depending on Zr concentration) the particles nucleate and also become fragmented so that their number density rapidly increases.
Ti plays a role as a growth restriction element and further refines the grain structure.
Effect of ultrasonic melt processing on the grain refinement in an Al–2% Ni–1% Mn–0.2% Zr–0.08% Ti alloy: (a) no ultrasonic processing (grain size 230 µm) and (b) with ultrasonic processing (grain size 72 µm).

This image includes qualitatively the crystalline information between polycrystalline grains.
This analysis shows that most grains have the texture of [111] direction normal to films, and a few of grains are oriented in the other directions.
The size of a- or b-axis oriented grains are relatively small, compared to caxis 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. 3) of BLT films on Pt electrodes.
Ferroelectric domains of c-axis orientated grains, which are indicated by 1, 2, and 3 numbers in Fig. 5(a) and (b), respectively, show no changes in the phase image as shown in Fig. 5(b), even after applied voltage of 10V.
C-axis oriented grains with plate-like morphology show almost linear dielectric behavior.

The number of active substrates in the domain of the melt with the undercooling ∆T below the liquidus may be calculated on the base of cumulative distribution function F(∆T) [31].
Mean number of active substrates in one cell: ( )STFNN max ∆= . (10) where: Nmax is the maximum specific number of the substrate for nucleation, S is the area of cell.
All graphite grains in this figures are black.
Every austenite grain has its constant gray level.
It was shown, that each austenite grain can coverage several graphite nodules.

The ECAP of the alloy results in the formation of ultrafine grained structure with a grain size of 0.8-3.5 µm independent of pressing routes and regimes.
However, at lower deformation temperatures, the plasticity and deformability of the alloy noticeably decrease because of a limited number of the effective systems of deformation.
Results and discussion The microstructure of the pressed and annealed Mg-Al-Zn alloy bar (before ECAP) is characterized by a substantial variation of grain size, from rather coarse (exceeding 15 µm) to fine grains (2.5 - 4 µm).
The ECA pressing by the regimes given in Table 1 resulted in the formation of ultrafine grained (UFG) structure with a grain size ranging between 0.8 and 3.5 µm.
The grain size in the magnesium alloy does not virtually depend on the ECAP regime and route.

Crack propagation behaviors in grain, effect of Schmid factor, propagation cross the grain or phase boundaries have been discussed.
The number of crack branches increase with increasing applied stress intensity factor range DK.
The result also shows that fatigue crack branching occurs mainly inside grains, and the number of crack branches seems also higher in the austenitic phase than in the ferritic phase.
Fig. 6a shows the main crack length versus the number of loading cycles.
Crack length versus number of loading cycles.

The germination characteristics such as germination rate, germinating, germination index, vigor index, and content changes of protein and nucleic acid in wheat grain were determined by germination bed method.
The contents of protein and nucleic acid in the grains affect on the seed germination and growth [2].
Germination rate/% = (Germination number / total of grain number for test) ×100% Germinating /% = (Germination number within 3days/ total of grain number for test) ×100% Germination index = Gt/Dv, Gt for germination number in t days, Dt for days Vigor index = G1S, G1 for germination index, S for sum the length of bud plus root Results and Discussions Effect of extract concentration of disused battery on wheat germination Wheat grain was placed in germination bed including the extract of disused battery for 216h, observing swell level of wheat germ every day, recording the change of germination per 100 wheat grains, the results are shown in Fig. 1, x axis is the extract concentration of disused battery, y axis is the germination rate, and z axis is the wheat grain culture time.
The wheat grains were soaked in 0%, 15%, 30%, 50% and 70% of extract concentration respectively.
The synthesis metabolism of nucleic acid is dominant with the increase of cell number during seed germination, the content of nucleic acid in cell enhance quickly.

When cooling rate is 2~5°C/s, the microstructure is mainly based on granular bainite and ferrite (Fig. 2b, Fig. 2c); as cooling rate rises further, the number of ferrite declines gradually yet bainite increases and lower bainite (LB) appears (Fig. 2d).
When the peak temperature of the second pass of double-pass coarse grain region is 1000°C (higher than Ac3), that is the supercritically reheated coarse grain HAZ (SCGHAZ).
The grains of ICCGHAZ remain coarse as that of primary coarse grain region, which is also one of the reasons leading to decreased toughness [8].
When the peak temperature of the second pass of double-pass coarse grain region is 650°C (lower than Ac1), that is the subcritically reheated coarse grain HAZ (SCCGHAZ).
(3) To avoid forming a large number of martensite due to rapid cooling, and to reduce welding joint cold cracking sensitivity, the weld preheating temperature should be controlled between 100°C and 150°C when X100 pipeline steel is field welding

This study will provide a stress - strain analysis based on molecular dynamics simulations of a series of metastable grain boundaries with identical crystal orientations but unique grain boundary characteristics.
The behaviour of grain boundaries (hereafter referred to as GBs) is complex.
Grain boundaries may be classified according to a characteristic known as the coincidence site lattice number (CSL) [7], also represented by ΣN.
Pond, On the interaction of crystal dislocations with grain boundaries.
McDowell, Asymmetric tilt grain boundary structure and energy in copper and aluminium.

The detailed process parameters and numbers of specimens were in Table 2.
(b) (c) (a) Fig.3 Austenite structures after multi-pass deformation (a) 1#, (b) 2#, (c) 3# Comparatively, the austenite grain size after four-pass deformation is small and relatively uniform with an average intercept of 33.59um; the austenite grains after five-pass deformation had uneven sizes and some of the grains were abnormally coarse, leading to a lager average grain size.
But the austenite grain size was uneven and the average intercept was relatively big.
Therefore, for multi-pass deformation, with the same strain rate and controlled accumulated deformation, the grain size of recrystallization austenite is mainly determined by pass temperature and deformation of each pass, especially deformation during the first pass has more influence, while has little relationship with the number of passes.
The ultimate deformation stress is determined by ultimate deformation temperature and increases with the increasing number of passes.

The result showed that it had excellent grain refining performance for commercially pure aluminum in 800˚C.
So far, AlTiB master alloy is still the most commonly used grain refiner in Al and Al alloys [3].
Research has shown that, AlTiC master alloy is considered as the most promising grain refiner of Al and Al alloy[6].
(a) 740˚C (b)800˚C (c)900˚C Figure 5 Refinement picture Figure 5 shows, AlTiC master alloy prepared at 800 ℃ has the best refinement, all of equiaxed grain, size can reach an aluminum (average grain size 0.026mm2) requirements; at 740 ℃, the temperature is low, refinement of AlTiC is bad, most of columnar crystals; at 900 ℃, the temperature is high, morphological of TiAl3 in the AlTiC master alloy changed, lowered refining effect, the center sites were equiaxed, columnar grain edges.
Reif, Development of Al-Ti-C grain refiners containing Tic.