Search results

Figs. 2(d)–(f) show the results for the specimens with large crystal grains.
The stress is smaller in the larger-grain specimen owing to the Hall–Petch effect.
Figs. 3(a)–(c) show results for the specimens with smaller crystal grains.
Figs. 3(d)–(f) show the results for the large-grain specimens.
Acknowledgement Authors gratefully acknowledge support from JSPS Grantsin-Aid for Scientific Research, Grant Numbers 18K03844.

Introduction The properties of nanograined intermetallics strongly depend on the grain size, the morphology of grains, the homogeneity of grain size distribution, the relative crystallographic orientations and the nature of grain boundaries [1,2].
Results Fig. 1 shows the variation of microhardness, HV0.2, against shear strain (γ) after processing by HPT for four different numbers of turns at (a) 473 K and (b) 573 K.
Fig. 2 shows XRD profiles for the samples processed at (a) 473 K and (b) 573 K after different numbers of turns including the initial powder mixtures.
The fraction of the Al3Ni intermetallic increases with increasing number of turns, i.e., increasing shear strain.
In addition, a peak broadening occurred as the number of revolutions increased, indicating the introduction of lattice strains, dislocation generation and grain fragmentation during the HPT processing [5,6].

of grains” means the number of grains where in GB, NGB, or IG-position is the indent located.
“Number of skipped grains in matrix” means the number of in-matrix-lying grains without indent.
“Maximum number of indent in 1 grain” means the maximum number of indents located in one grain, the indent lies inside the grain.
Number of measured grains increases with increasing distance between indents for the same number of indents, however the number of skipped grains increases and therefore measurement efficiency is decreasing.
Number of inside-grain indents depends on microstructure.

In grain boundary junctions of ferrite second-phase the particles are always globular.
Moreover, grain pearlite (Fig. 3, b), dominates over lamellar one (Fig. 3, c).
In grain volume and on grain boundaries the second-phase particles are observed.
In grain boundary junctions the second-phase particles are always globular.
Otherwise, a great number of pores form.

Grains of the top of the work-piece were refined.
Grain size after upsetting Fig.4.
Upsetting helped the grain refining largely in the heart of work-piece, but made the distribution of grain size inhomogeneous while stretching could make the distribution of grain size on the work-piece homogeneous, and the grain size was refined by the increase of drawing steps.
The grain fineness number of this part was tested as 6.5.
The grain fineness number of the middle part of steering extending arm was tested as 6.5.

Plate-like grain microstructures formed on the bottom part of the pellet, and vicinity of the surface was dense.
The plate-like grain was oriented in the ab-plane direction.
A number of studies have investigated the preparation of In2O3(ZnO)m as new transparent conducting electrodes for use in a variety of electronics devices, and the synthesis of a highly electrical conductive compound In2O3(ZnO)3 in a solid state reaction at low reaction temperature is required.
In the present study, since the ab-plane direction of the In2O3(ZnO)3 grain has high electrical conductivity, the plate-like grain was grown selectively.
In addition, for the silica substrate the plate-like grain was deposited by microwave heating.

Grain Boundary Velocities, v.
Sub-grain Boundary Growth.
The sub-grain mobilities were estimated from the average growth rates of large numbers of sub-grains during more standard annealing experiments outside the SEM.
Grain boundary velocities and mobilities.
ii) Sub-grain mobilities in the same alloys measured during sub-grain growth using a FEG-SEM gave mobilities one or two orders of magnitude lower than the grain boundaries but, quite surprisingly, mobilities close to those of a similar Al-Si alloy.

The grain size of primary α-Al grains was measured using ASTM E1382 linear intercept method.
The shape factor of primary α-Al grains and the secondary Al grains were also determined.
Number, size and distribution of pores were thus determined using the software package Volume Graphics Studio Max 3.3.
The number density is only 0.024 mm-3.
The number density is 159 mm-3.

Introduction Over the last decade, a number of techniques collectively referred to as severe plastic deformation (spd), have emerged as a promising approach for the production of bulk ultrafine-grained (ufg) materials [1].
As expected, grains were severely elongated in the region recognized by the number 2.
The grains in the region are highly elongated, showing extensive plastic flow.
Formation of shear bands may explain as follows: elongated grains along the shear bands are generated in the favor path which depends on die geometry and billet size and then fragmentation of (a) (b) Adiabatic shear band 1 2 3 the grains into equiaxed smaller grains.
The shear bands contained much finer grains compared to the bulk materials.

To mimic the geometrical arrangement of AlN precipitates along austenite grain boundaries, a new model for precipitation at grain boundaries is used, which takes into account fast short-circuit diffusion along grain boundaries as well as the slower bulk diffusion of atoms from inside the grain to the grain boundaries.
Also, the number of available theoretical treatments of the precipitation process of AlN is rather limited.
To take into account the geometrical arrangement of AlN precipitates along austenite grain boundaries, a novel model for precipitation at grain boundaries is used [35].
A default grain size of 50 µm is used in all simulations unless stated otherwise.
Thus, the grain sizes used in the simulations are only estimated values.