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Despite the vast number of studies the effect of the initial structure on the evolution of microstructure is not well understood.
On this face the initial grain boundaries align all at an angle of about 60° with respect to the torsion axis.
At an equivalent strain of 6 the microstructure size decreases due to the fragmentation of the original grains.
The original grain boundaries are easily identified after the polishing process, because the boundaries behave more unstable during electrolytical polishing, which leads to grain boundary etching.
In the (111) pole figure shown in Fig. 5e only a few grains of a size of about 60µm contributed to the pole figure evaluation.

The composite SW11 (Fig. 2a), atmosphere-switched at 1100°C, shows relatively homogeneous microstructure with equiaxed grains, while the microstructure of composite SW45 is characterized by exaggerated grain growth (Fig. 2b).
However, as expected in microstructures of Fig. 2, the maximum sizes of matrix grain are increased with the increase of switching temperature.
The presence of exaggerated grains in composite atmosphere-switched at high temperature may be directly related to the increase in inclusion size.
Consequently, this uneven distribution locally induces the inhomogeneous microstructure with exaggerated matrix grains due to ineffective role of inclusions as a grain growth inhibitor for the matrix grains [8].
Composite Matrix grain size (µm) Inclusion size (µm) Fr. strength (MPa) SW11 0.67±0.33 (2.2) 0.19±0.07 (0.5) 819±53 SW12 0.70±0.34 (2.4) 0.21±0.09 (0.6) 736±97 SW45 0.67±0.37 (3.0) 0.30±0.14 (0.8) 606±198 * Numbers in parentheses represent the maximum size.

Composites sintered at lower temperatures have finer grain sizes as the grains do not have enough energy to grow to a larger size and enter extended grain growth stages.
The grain size of composites sintered at 1400°C is the biggest among all the composites.
Density which gradually increased at higher sintering temperatures inevitably decreased the number of pores.
The micro-hardness could also be affected by both relative density and grain size.
Smaller grain size increases the frequency with which dislocations encounter grain boundaries, thus requiring larger stresses for deformation to occur [7-8].

From the existing literature, a significant number of closely related works are found.
Reynolds Number, Re=ρ×vg×Ddμ (7) So, Re =ρ×vg×Ddμ=1041.9, and Cds = 0.58; similar to the reported experimental values [18].
The alignment of the grain formation confirms the directional component of the grain growth for the sub merged arc welding process of 2.84kJ/mm heat input.
In the context of this equation one can say that the hardness of the grain growth portion will also manifest lower values related to higher grain sizes.
In the grain growth portion of the welded region longer grains have been found depicting the chances of dislocation, slip, low yield strength and low hardness values measured in Rockwell scale B. 7.

In a comparison of microstructure characteristics of the joints, the joint that showed the maximum impact strength had the formation of fine needle-like grain in the weld.
Jeshvaghani et al. [5] applied a Shielded Metal Arc Welding (SMAW) process for coating a ductile iron by a different alloying element electrode and a different welding pass number.
The high hardness at the fusion line was caused by the formation of the WC layer, the modification of fine grain, or the formation of the martensitic phase in the melted area [6], etc.
When the high amount of chromium, molybdenum, and manganese were increased, WM grain was affected to change from the round grain shape to a needle-like shape as demonstrated in Fig. 10e-f.
- An important microstructure characteristic of the joint that provided the maximum impact strength was the formation of small and fine needle-like grain shape in the weld metal.

In 1980s’, the exploitation in the whole province was 130×108 m3/a, the exploitation in Hebei plain reached 120×108 m3/a, the number of well was 60×104 and the irrigation area reached 287×104 hm2, the well depth was 170-350m.
Impact of Change of Grain Output on Water Resource Hebei is a big agricultural province [4].
Since 1970s’, the total grain output of Hebei has always been the tendency of increasing.
The grain output was 1272.5×104 t in 1970 and 1522.4×104 t in 1980 respectively.
And the grain output in 1998 reached 2917.5×104 t, which was 2.3 times higher than that in 1970 (figure 1).

In the wafer numerous grains can be identified and localised with a mosaicity in the order of 0.05°, whereas the whole wafer shows a mosaic spread of around 0.1°.
Journal Title and Volume Number (to be inserted by the publisher) 2 Experimental A bulk crystal with a diameter of 55 mm and a thickness of 20 mm as well as a 2 inch diameter wafer of 300 µm have been investigated.
Journal Title and Volume Number (to be inserted by the publisher) 4 of the crystal parallel to the horizontal direction.
Similar measurements on the wafer allowed to identify and localise numerous grains (see Fig. 2c) in accordance with previous results (see [6]).
Individual grains have mosaicities in the order of 0.05°, whereas the peak width over the whole wafer shows an angular spread of around 0.1°.

They are associated with a high number of involved process and design parameters.
Grains.
Substructure in Grains.
White lines indicate square cross-section of columnar grains.
Each grain shows a particular orientation of these needles.

Introduction Duplex stainless steels are used in a number of advanced applications for example in oil, gas and chemical industries due to their good mechanical properties and corrosion resistance [1,2].
The materials differed in grain size with the hot rolled materials showing a considerably smaller grain size.
These two oxide nodules are associated with the two austenite grains in the substrate and the inner oxide is growing into these austenite grains.
No nodules were observed across the sample on either the ferrite or austenite grains.
On the polished surface finish, nodules form on the austenite grains and grow into the substrate on the austenite grains.

Sr and Ca were also chosen as the alloying element since fine precipitates are expected to form and to play a role in reducing the grain size.
The improved ductility of the Sn-added alloy may be partly explained by reduced grain size, even though the effect of grain size on mechanical properties is complicated due to the initiation of discontinuous dynamic recrystallization [5].
The Sr- added alloy showed the smallest grain size in both as-cast and as-rolled conditions.
Since the dynamic recrystallization takes place at a greater rate for a finer grain size due to the higher number of nucleation sites, the as-rolled grain size tends to be proportional to the initial grain size.
It is suggested that the Mg-Zn-Sr phases could hinder the recrystallization process by interfering with the grain boundary movement.