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The effect of asymmetric rolling with cone-shaped rolls on ultra-fine grain evolution was investigated.
Introduction Ultrafine grain (UFG) size in metals and alloys is known for its positive effect on their mechanical properties.
The smallest grain was observed in surface region after reduction of 23% at 900 °C (0.092 μm).
Noteworthy that at relatively low temperature of 900 °C the grain is severely refined up to UFG level.
Microstructural observations revealed the non-uniformity of grain size distribution across the thickness of the specimen with larger grains in the central region of the specimen during asymmetric rolling in cone-shaped rolls and smaller grains up to UFGs in surface region.

This latter definition does not include the microstructure, i.e. the positions of the grains in the material.
The basic processes like plastic deformation, nucleation, and grain boundary movement are anisotropic.
The slit was 0.1mm and very small grains are imaged.
Bigger grains are seen as longer streaks with the streak-length corresponding to the grain diameter in scanning direction (transverse direction).
The Recrystallization of AlMn1 Investigated by Pole Figures by Number.

The two models tested were (1) a reduced model having the form of Eq. 1 with 3 parameters: e.g. oε& , n, Q and; (2) a complete model having the form of Eq. 1 with a total of 6 parameters: 57oε& , 59 oε& , n57, n59. 57Q , 59Q , where the numbers refer to the billet number.
Wakai assumed that the grains in the creeping body were separated by a liquid phase.
At the grain surface the liquid changed its structure so that a distinct absorbed phase existed there.
Role of Grain Boundary Viscosity.
The thickness of the grain boundaries depends on the size of the rare-earth cation; grain boundaries containing smaller rare-earth ions like Lu+3 tend to be narrower than grain boundaries containing larger rare-earth ions such as La+3 [16, 41].

The results show that the average grain size and surface roughness of the Cu thin films deposited at an acceleration voltage of 3 kV is smaller than other conditions.
The surface roughness of Cu thin films is of importance in a number of microelectronic device applications as well as in other technologies.
For the Cu films deposited by ionized cluster beam at Va =3 kV, the average Cu grain size is smaller than other deposition conditions.
It can be seen that the Cu grains deposited at 5 kV tend to be larger than those formed at lower kinetic energies.
In the ICB deposition, the qualities of the films is influenced by the ratio of the number of ionized clusters to the total number of clusters.

This will shift our nominal compositions out of the sialon plane and the phase relationships between the Journal Title and Volume Number (to be inserted by the publisher) 3 transient liquid phase and sialon will change.
All investigated compositions indicate a fine-grained microstructure with mean grain sizes between 1-3 Mm.
An increase in additive excess results in a more homogeneous microstructure and a significant aspect ratio increase of the �-grains while the grain morphology of �-grains remains equiaxed.
Journal Title and Volume Number (to be inserted by the publisher) 7 La-ions basal plane prism plane Fig. 6: Schematic of an adsorption layer rich in larger rare earth cations which reduce the growth in diameter
The other parameter is a weak interface between grains and grain boundary phase (residual glass).

The key material parameters in micromechanical modelling are resistances to crack propagation: along grain boundaries and through grains.
It contains significant number of grains, representative for the whole sample.
In case of porous ceramics it consists of polygon grains and grain boundaries with pores initially spread inside grains and along the grain boundaries.
This is due to fact that surface fracture energy of grain boundaries (γgb) is significantly less in comparison to surface fracture energy of grains (γg), i.e.
Npo is the number of pores and Ncr - the number of cracks in the RSE.

The curing depth decreases with a decrease in grain diameter and with an increase in grain percentage.
The abrasive grain was WA#1000 and the grain percentage was 25 vol.%.
Forming method Free-surface method Exposure method Plane-exposure method Layer thickness 300 µm Numbers of layer 40 Light intensity 18 mW/cm2 Exposure time 3 sec Working size φ50 mm ˜ t12 mm Abrasive grain WA#1000 Grain percentage = 25 vol.% Table 2 Grinding conditions.
The abrasive grain is WA#1000 and grain percentage is 25vol.%.
Since the fabrication time in stereolithography is in proportion to the stacking number, a grinding wheel with a thickness of less than 30 mm will be fabricated within 15 min under the present fabrication conditions.

Keywords: HPHT Sintering, High Pressure, Hardmetal, Densification, Grain Growth. 1.
Soon WC was used in a number of materials and more recently also in coatings [2].
Number of samples P/T/t Number of samples P/T/t 4 5GPa/780oC/2min. 4 5GPa/1350oC/4min. 4 5GPa/1200oC/2min. 4 5GPa/1400 oC/2min. 4 5GPa/1350oC/2min. 4 5GPa/1400 oC/4min. 3.
If parameters are chosen to encourage the latter, then there is a risk of excessive grain growth.
Temperatures up to 1350 ºC promotes abnormal grain growth and pore coarsening, as well as times up to 2 minutes.

The images show a noticeable decrease in grain size with the carbides concentration incensement.
When the liquid metal cools down, TiC particles act as crystallization centers, increasing the number of grain nuclei.
The only exception to this rule is strengthening by grinding grain.
Fine grains lead to an increase in strength properties due to the hardening of grain boundaries and can contribute to an increase in plasticity by providing more grains with sliding planes and sliding directions in the direction of maximum shear stress during tensile tests.
The increase in strength is explained by grain grinding and well-bonded TiC particles.

Introduction Grain elevators belong to both concrete and metal structures, which are widely used in construction [1-3].
Small farms and the farmers do not have such facilities to pay for grain storage.
They use warehouses, which are not suitable for long term storage and grain loses its properties.
As grain loses its quality farmers so and farmers bear financial losses.
Reinforced concrete structures don’t react so strongly to sudden changes in temperature, and climate control inside the housing can be kept with a smaller number of technological equipment.