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These grains are numbered 018, 023 and 045, and had the following initial orientations: 018 = 27°/ND rot.
The very wide spreads include some Cube and a much higher proportion of b fibre components. a) grain 018, b) grain 023 and c) grain 045.
a) b) c) Fig. 4 Texture component map of 3 grains (initially 20-30° rotated Cube) after e=1.2 rotated to Cube/b fibre orientations. a) grain 018, b) grain 023, c) grain 045.
(a) grain 45, (b) grain 129 and (c) grain 177.
The simulation part of this work has been achieved during the postdoctoral position of R.Q. at Cornell University, for which partial support has been provided by ONR, under grant number N00014-09-1-0447 and N00014-05-1-0506.

The infrared transmittance in the wave numbers of 1500-4000 cm-1 is less than 15 %.
Experimental procedure Ti powder (< 75 μm average grain size, ≥ 99.0 wt% purity), Si powder (< 75 μm average grain size, ≥ 99.9 wt% purity), B4C powder (< 154 μm average grain size, ≥ 99.0 wt% purity) and C powder (<75 μm average grain size, ≥ 99.0 wt% purity) were put in constant temperature drying oven at 120°C for 2 h, and mixed respectively according to the following chemical reactive equations
TiSi2 has been crystallized finally with a grain diameter of about 100-200 nm and distributed on the grain boundary of Ti3SiC2 grain due to its lower melting point (1480 °C), which has been avoided in service parts for the heat.
It can be seen that grains are in irregular shape, and the average grains size are under 350 nm.
However, the light transmittance of Sample B is dropped to below 15 % in 1500-4000 wave numbers/cm, and that of Sample C is dropped to 5%-11% in 1500-4000 wave numbers/cm.

As it is shown in the histogram of the size distribution of grains (figures 5) average grain size of both alloys is 80 nanometers.
The nanometer-sized clusters differ from the bulk alloy in that the nanostructured clusters have a larger numbers of interface atoms (including atoms on grain boundaries), especially while cluster size is small.
The overwhelming amount of interface atoms, incomplete in atom bonds, leads to less regular atom configurations bearing a lower number of the nearest-neighbor atoms, which make the Curie temperature Tc decrease.
The increasing of the MCE values during decreasing values in grain size can be also explained by suppression of local magnetocrystalline anisotropy which is associated with each individual grain.
Müller K H and Schultz L, Evolution of interaction domains in textured fine-grained Nd2Fe14B magnets. 2007 J.

A characteristic feature of a material with a large number of fine grains is a significant increase in the total surface area of the grains and an increased proportion of the volume of intergranular space compared to coarse-grained materials.
First of all, cooling after being melted, components with a high melting point begin to form a crystal lattice and a fine-grained structure in the presence of an increased number of crystallization centers.
As each grain passes near neighboring grains, the deformed layer experiences a deformation effect from the contacting grains.
As we go through each grain of adjacent grains, the deformed layer is affected by them.
Chukanov, etc., From the history of the superplasticity effect of metal systems, in: Algebra, Number Theory and Discrete Geometry: Modern Problems, Applications and Problems of History.

An average prior β grain size of approximately 350µm was obtained at 1060°C, although grains on the order of ~800µm were also observed.
The αp grains, which are located at prior β grain boundaries, appear to significantly retard β grain growth resulting in a relatively fine β grain size similar to the as-received material.
However, a limited number of samples tested at this temperature displayed only minor amounts (<5%) of αp, which was possibly a result of test-to-test variations in actual sample and/or test conditions.
At the center of specimens, original prior β grains are elongated transverse to the compression axis with grain boundaries displaying a wavy nature.
The limited number of dynamic recrystallized grains is consistent with the favourable recovery characteristics of the bcc crystal structure.

Roughness and grain size of substrate and samples no. 1 to 9 investigated by AFM Sample no.
Roughness and grain size of samples no. 10 to 19 investigated by AFM Sample no. 10 11 12 13 14 15 16 17 18 19 Rough-ness [nm] 2.5 µm2 0.59 0.33 0.23 0.47 0.24 0.25 0.67 0.76 0.68 0.34 5 µm2 1.53 0.61 1.14 0.84 0.98 0.47 1.91 1.14 0.87 1.20 Grain size [nm] 4.0 2.25 3.90 2.25 2.75 1.60 3.20 6.85 3.20 2.0 a b c Fig. 2.
All the samples were obtained with very fine nanostructure, as the grain size was less than 10 nm, with 2 exceptions (samples no. 5 and 7).
Acknowledgements This work was supported by a grant of the Romanian National Authority for Scientific Research, Program for research - Space Technology and Advanced Research - STAR, project number 68/2013.
“This paper is supported by the Sectoral Operational Programme Human Resources Development (SOP HRD), financed from the European Social Fund and by the Romanian Government under the project number POSDRU/159/1.5/S/134378”.

The measurement showed the region achieved a reasonable equiaxed grain structure with an average grain size of d » 60 nm.
The Al-Cu system demonstrated a consistent trend of microstructural evolution with the Al-Mg systems during HPT with increasing numbers of turns.
With increasing numbers of HPT turns for 20 and 40, a gradual expansion was observed in the severely mixed edge regions.
Significant grain refinement was achieved to demonstrate true nanostructure with an average grain size of d = 30 nm in an equiaxed microstructure.
Langdon, Twenty-five years of ultrafine-grained materials: Achieving exceptional properties through grain refinement, Acta Mater. 61 (2013) 7035-7059

The effects of workpiece hardness, holding time and cooling methods in annealing and the number of grain layer are investigated.
Table 3 Specifications of micro swager Number of dies 3 Die inclusion angle [°] 12.5 Feeding rate of wedge [mm/s] 0.38 Stroke of wedge [mm] 20 Motor power [W] 150 Motor speed [rpm] 200 Results and Discussion Hardness Test.
The number of grain layers was not observed because of the residual work hardening by the prior drawing process.
There are about 2 to 3 grain layers and with carbide precipitated in some grains.
Table 4 Results with swaging tests Holding time 10 minutes 45 minutes 90 minutes 1-6 Hours Furnace -cooling G2: cracks; grain layers: NA G3: breaks; grain layers: NA G2: sound; grain layers: 2 G3: fair; grain layers: 2 (Fig. 6) G2: cracks; grain layers: 2-3 (Fig. 7) G3: breaks; grain layers: 1-2 Water -cooling G1: fair; grain layers: 4 G2: sound; grain layers: 3 G3: breaks; grain layers: 2 G1: fair; grain layers: 4 (Fig. 8) G2: sound; grain layers: 3 (Fig. 9) G3: cracks; grain layers: 2 G1: cracks; grain layers: 2 G2: sound; grain layers: 2 G3: cracks; grain layers: 2 Fig. 6.

The average grain size was determined by SEM micrographs using the linear intercept technique by counting at least 500 grains and by multiplying the average linear intercepts length by 1,56.
The grain size distribution was measured based on an appropriate number of SEM images of each sample.
A large number of micrographs were obtained from each sample, allowing for the measurement of more than 150 individual grains.
Grain size distribution of samples heated to 1500ºC/2h and heated to 1050ºC/2h followed 1500ºC/2h.
The two-step sintering, which the alumina is heated at a higher temperature and then cooled, it was present more homogeneous sintered microstructure, coupled with a smaller mean grain size and narrower distribution in grain sizes.

This unusual behavior of deformation bands and their features depending on the grain size are discussed.
Moreover, there is no general line for the effect of the grain size reduction on the jerky flow.
This result may be related to an increase in the number and strength of obstacles to the motion of dislocations due a combined effect of both grain refinement and nanosize particles, which locally harden the material and generate internal stresses promoting plastic flow in the neighboring areas.
Summary In summary, the PLC effect was investigated in an Al–Mg–Sc alloy with two grain sizes.
Lloyd, H.Jin, Inhomogeneous yielding and work hardening of a fine grained Al–Mg alloy, Mater.