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Nano-crystalline materials, which were speculated to possess physical and chemical properties substantially different from conventionally grain-sized materials, have been proved to be easily produced by MA.
The number of participants in ISMA, despite limited preparation time, far exceeded our expectations.

In an ideal, theoretical case, all specimens at a certain stress level would fail after the same number of cycles.
Fatigue stress vs. number of cycles: composite with fibers from car tire cords.
Fatigue stress vs. number of cycles: composite with steel fibers.
Fatigue stress vs. number of cycles: composite with polypropylene fibers.
Keršner, Change of a Crack Propagation Rate in Fine-Grained Cement-Based Composites Due to Partial Replacement of Aggregate by Ceramic Waste, Key Eng.

The magnitude of the internal friction strongly depended on the elevated temperatures and the cycle numbers of the torsional loading.
Unidirectionally solidified Al2O3/YAG eutectic consists of single crystal sapphire and single crystal garnet phases and these phases are tangled each other without grain boundaries [1].
The decreasing shear modulus can be considered as the result of grain boundary sliding.
Since single crystals of Al2O3 and YAG are tangled each other without grain boundaries in the eutectic sample, no boundary sliding and no decreasing of shear modulus can be observed.

Numerical simulations by using finite element code DEFORM-3D show that the number of roller pairs had significant influences on the the CR-ECA deformation procedure.
Introduction In the past decades, severe plastic deformation (SPD) procedures such as equal-channel angular extrusion/pressing (ECA-E/P) and high-pressure torsion (HPT) have been extensively investigated and proven to be very effective tools for achieving grain refinement and beneficial crystal orientation for plastic forming [1-3].
The number of roller pairs used for the simulation was 1, 2, 3 and 4, respectively.
It can be seen that as the number of roller pairs changed from 1 to 2, 3 and 4, the output velocity increased from 3.029 to 3.355, 3.512 and 3.465 mm/s, an increase respectively by 10.8 %, 15.9 % and 14.4 %.
The number of roller pairs had significant influences on the the SPD deformation procedure.

Railway construction is a linear distribution, so it is appropriate to set the concrete centralization batching plant near the masonry number of focus point.
Coarse aggregate affects pump concrete seriously, because the particle size of coarse aggregate is strictly limited by the diameter of the pipeline, and the ratio of maximum grain to size pipe size shall not be more than 1:3.
The granularity of the sand had a greater influence on the pumping effect; less fine-grained content is not conducive to pumping.
Pump concrete mixed with fly ash is to improve the pumpability, because the pumpability of concrete is bound up with the content of grains under 0.15mm in mix proportion.

(1) 2- Using grain size and surface roughness: another method for obtaining the FLC is to relate the grain size and surface roughness of the sheet to geometrical inhomogeneity.
(2) Where R is the initial surface roughness, d0 is the grain size and K is a material constant.
To derive the empirical law, a large number of experimental data (for common types of steels and aluminum alloys) were collected from the literature and the appropriate values of N were determined for them with trial and error method.

A grain size of 55 μm was obtained by measurement of the specimen.
For laser-peening, the pulse energy was 60 mJ, the diameter of a spot was 0.7 mm and the number of laser pulses was 70 pulse/mm.
Stress value was determined by the cos2χ method with a rotation in consideration of the coarse grain problem [4].
The micro-stress in this study means the stress of each grain and can be obtained using each lattice plane.

If the holes and crevices in soil reflected by soil structure and the contact surface between soil grain or mass that has relatively feeble cohesion are treated as defects in soil, non-uniformity of soil strength can be deemed as visual representation of these defects.
By analysis from the perspective of damage mechanics, the voids in soil and contact surface between soil grain or mass as well as tiny cracks and crevices of various types and sizes are defects in continuous media.
Clearly all curves fall into 4 stages: the first is linear elastic stage that reflects compacted structure under intact condition, featuring closing of micro cracks, macro void turning into micro void; the second is pre-peak damage incipient stage, in which, as stress rises, slippage occurs between soil grains; damage occurs in structure; and shear zone begins to emerge; The third is rapid expansion stage of damage after peak stress, in which shear zone tends to grow thicker.
This model has the following advantages: (1) This model that has considered threshold value of damage stress can better describe the full process of deformation damage of loessial soil with various moisture contents under different confining pressures. (2) This model has revealed that structural damage of loessial soil is caused by combined action of stress status and immersing humidification. (3) This model features smaller number of parameters and convenience for applications.

A large number of automobile products are made from iron-based alloying powders; that is why in recent years there have been performed experiments aimed at using plasma nitriding processes for metal powder sinters [7-9].
The morphology of the porosity changed from open to closed, and round upon the additions of boron however, liquid phase sintering in the presence of the highest boron contents, enables dramatic grain growth, especially in the Astaloy Mo samples in which a reduced amount of alloying elements (if compared with Distaloy SA samples) did not obstruct this growth [8].
In turn, in nitrided sinters with lower porosity degree, sinter grains might have not only crumbled acting as extra abradant, but also increased the friction coefficient.
In turn, in nitrided sinters of lower porosity degree, sinter grains might have crumbled acting as extra abradant, and in consequence, could have increased the friction coefficient.

The λ parameter may be varied within wide limits, by varying the dimension of grains and keeping constant their volumetric concentration, or by maintaining constant the dimension of grains and modifying their proportion in the alloy.
We will observe the following practical aspects: • The conditions of the penetration process, when injecting powders in the melted metal matrix, with direct applications for WC, TaC and NbC; • The specific characteristics of the solidification process in the presence of carbide grains and the influence of the solidification process on the dispersion of the hardening phase; • The hardness of the carbides alloyed layer; • The wear hardness of the layer.
In accordance with Stoke's law, there is a linear dependence between the coefficient of friction (µ) and Reynold's number (NRe) [10].