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Therefore, when the grain size of a polycrystalline aggregate is reduced, the fraction of atoms at structurally disordered sites increases while the number of atoms at perfect lattice sites decreases.
However, this number can be substantially increased to over 80% in what is referred to as grain boundary engineering.
It should be noted that the value of 0.48 B for site 1 does not significantly reduce the total moments associated with the 5 boundary, since Ni (1) sites constitute only a small portion of the total number of atoms in this boundary.
Note that the hardness values in this figure are given in units of Vickers Hardness Numbers (VHN).
The Taber wear index is usually given as a unitless number: the lower the Taber wear index the higher the material's resistance to abrasive wear.

For example, FSP of 99.999% aluminum leads to a minimum grain size of ~50 μm but much smaller minimum grain size of 3.5 μm is achieved in 99.99% aluminum [7].
FSP was conducted to investigate the minimum grain size of Al-0.01%Fe, which was compared with the grain sizes of other processed pure aluminums　[1-4, 7-8, 12-18].
A grain was defined an area surrounded by HAGBs, and the grain size (d) was defined the diameter of a circle with the same area as that of the grain.
However, the grain size remained almost unchanged over 1016 s-1.
Acknowledgements This work was supported in part by JSPS KAKENHI Grant Number 15K21294, the Light Metal Educational Foundation Inc., the Japan Aluminium Association, and the Nikki-Saneyoshi Scholarship Foundation.

Temperature and Humidity Measurement System for Grain Storage Based on nRF905 Yang Shulian1, a, Shen Jin2Li Zhenmei3, Tan Boxue4 and Zhao Kai5 1, 2,3,4,5 School of Electric and Electronic Engineering Shandong University of Technology, Zibo, China a email-yangsl21cn@163.com Keywords: temperature and humidity measurements; Wireless communication; nRF905; grain storage.
A temperature and humidity measurement system for grain storage is developed.
Introduction Temperature and humidity measurement using Microcomputer is an indispensable means for safe stored grain in silo.
General System The diagram of measurement system for grain storage is shown in figure 1.
With the increase of the number of greenhouse, and being greater the area of its cover, the transmission power of nRF905 does not meet the actual demand, thus the circuit of amplifying power based on the chip of PA2423L is designed to improve systemic output power and realize further receiving and transmission distance.

Introduction Equal channel angular pressing (ECAP) is the representative model technique of severe plastic deformation (SPD) refining the grain size of metallic materials down to the sub-µm level, so called ultrafine grained (UFG) materials.
In the flat area, individual grain did not appear explicitly, and grain boundary sliding (GBS) hardly occurred across the boundaries.
The flat areas seemed to be agglomerates of grains having low angle boundaries.
In addition, a number of boundaries were well-defined, and showed sharp offsets of marker lines.
The deformation mode was changed from dislocation viscous glide to grain boundary sliding by additional rolling resulting in the development of larger portion of high angle grain boundaries. 3.

The results showed that grain size and domain size were small before HT,there was  high-density dialocation in the alloy.After HT,grain size  increased, the internal stress, dislocation and other defects were reduced,magnetic domains became wider,the number of the domain decreased and the exchange energy between the magnetic domain reduced,leading to the decrease of the coercivity and increase of permeability.It was also found that the curie temperature was not changed after heat treatment.
As to the grain size, the large grain size is preferred due to the decrease of the coercivity [10,11].The grain size increased and the area of the grain boundary reduced after heat treatment, reducing moving resistance of the domain wall and increasing movable distances of the domain wall in grain.
The grain size increased after heat treatment, making the coercivity(Hc) lower.
(2) The number of domains  reduced with the domain becoming larger,the exchange energy between magnetic domains and the energy of magnetocrystalline anisotropy reduce, which reduced the coercivity and increased the magnetic permeability
Interactive Effect of Grain Orientation and Grain Size on Magnetic Properties of Fe–78 wt% Ni Ribbons.

Their room temperature tensile properties were examined and compared to those of coarse grained counterpart.
Introduction The advent of innovative severe plastic deformation (SPD) techniques makes the grain size of metallic materials be easily refined to the submicrometer level, so-called ultrafine grained (UFG) materials.
UFG materials are quite attractive due to their ultrahigh strength, more than twice of the coarse grained counterparts.
Both ferrite grain size and martensite island size were ~1.3 µm and the martensite volume fraction was about 28 %.
The microstructure of the ECAPed low carbon steel is characterized by UFG ferrite grains with a high density of lattice dislocations, subdivided pearlite colonies, and a large number of low- and high-angle boundaries with extrinsic boundary dislocation, etc [8].

The preliminary observations data show complex temporal and seasonal variation in estuarine flocculation of fine-grained sediment.
Introduction Approximately 90 percents of the suspended sediment load transported from the Yangtze River to its estuarine and coastal areas consists of fine-grained particles with dispersed medium grain size of smaller than 32 μm.
Flocculation processes change physical characteristics such as original size, density and settling velocity of fine-grained sediment [1].
In other words, below the critical τ, the increased τ could promote the suspended sediment re-flocculation to large flocs by increase number of particle collisions per unit time, and lead large suspended sediment flocs break-up to small ones above the critical τ.
Estuarine macroflocs and their role in fine-grained sediment transport [D].

By this method, the material grain size can be refined to 20~200nm, which are nanometer level.
Fig. 5(a) is a line chart of the effective strain of these seven points when the number of torsion is 0.5, 1, 1.5 and 2.
The grain gets finer and more homogeneous when the number of turns increases [7].
This is the reason for the central area owns a larger grain size but edge area owns a smaller one.
This inhomogeneity gets smaller, and the strain increases with the number of turns increases which get the grain refined.

The size effect occur in thin metal foils because of low number of grain.
The surface roughening in coarse grain, increased higher than in fine grain.
The inhomogeneous grain strength in coarse grain is higher than fine grain in SUS 304 thin metal foil.
Conclusion In SUS 304 thin metal foil, the Ra increases higher for coarse grain than fine grain, because of the lower slip band intersection in coarse grain that affect to lower MPT in coarse grain, compared to fine grain.
In SUS 316 thin metal foil, the Ra increase higher for coarse grain compared to fine grain, because of GMO lower in coarse grain compared to fine grain that affect to more inhomogeneous grain strength in coarse grain compared to fine grain.

It was found that creep behaviour is strongly dependent on number of ECAP passes.
Fig.2 shows Vickers hardness HV as a function of the number of ECAP passes.
This difference consistently increases with increasing number of ECAP passes.
Increasing elongation together with increasing number of ECAP passes indicates that high-angle grain boundaries have a lower strengthening effect under creep than low-angle ones.
High-angle grain boundaries were formed with increasing number of ECAP passes and actively influence creep properties.