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PIRAC as well as PVD nitriding of Ti alloys at T>800°C may result in coarsening of grain size and as a result in reduction of the fatigue resistance [8].
In the present work, Ti alloys were PIRAC nitrided at the relatively low temperatures of 700-850°C in one and 3 stages with the goal to avoid grain coarsening, obtain thicker TiN based coatings with and keep the excellent adherence of the coating to the substrate.
The coatings produced by the 3 stage PIRAC process show a more gradual change of microhardness as a function of a distance from surface and higher microhardness numbers at the same depth as compared to one stage PIRAC process (see Fig.7) indicating it has a thicker Ti nitride layer.

The microstructure of the as recevied is composed of large number of flake pearlite and small amount of ferrite, it may be caused by higher cooling rate of air cooling after hot rolling and it is not acceptable for plastic deformation.
When the tempering tempreature is lower, such as 540°C and 580°C, the tempered sorbite retains the orientation of the quenched martensite because the sorbite generates along the martensite grain boundary.
It needs larger energy to make this kind of grain sliding which needs larger plastic deformaion force.

In low stress condition, the surface morphology shows a number of voids (Fig.5b-3), indicating that the final failure may be related to the accumulation of these voids.
In high stress condition, grain boundary sliding (GBS) is predominant (Fig.5b-1) and may lead to the final failure.
While grain boundary sliding may be the dominant mechanism leading to failure in the high stress region, the accumulation of voids leads to final failure in the low stress region.

At lower forging temperatures (1000°C), the microstructure consists of primary α and a small amount of primary β grains mixed with a newly formed fine lamellar α-β grains.
Underneath the well defined porous layer the number of pores is gradually decreasing, with few very small remaining pores in the middle part of the discs.

A number of cutting experiments with single abrasive grit were performed to study the mechanism of grit-workpiece interaction [1].
Simulative model of single grit cutting Geometric Model of Single Grit In authors’ previous research, white light interferometer was employed to measure the surface topography of alumina grinding wheels with different grain size [8].
Rong, Research on microscopic grain-workpiece interaction in grinding through micro-cutting simulation, part 2: factorial study, Adv.

All methods are based on assessment of a high number of penetration tests at locations affected by seismic activity, where in some, liquefaction of soils in the ground has been observed while in others, liquefaction has not occurred.
Fig. 2 Examples of CRR curves used in the respective methods Fig. 2a [3], Fig. 2b [4] Correction of measured penetration resistance qc is based on consideration of the magnitude of effective geostatic stress or consideration of the content of fine-grain particles in the soil.
The granularity of brown-coal ashes corresponds to fine-grain sand to silty sand.

Fig. 1 Model for analysis of slope stability Selection of parameters in shear resistance Gangue formed with large grain sizes, high coarse grained content and poor gradation, is different from normal soil.
Table.3 Result of orthogonal test test number Factor and level Evaluation index density γ/[kN·m³] cohesion c/[kPa] angle of friction φ/[°] angle of slope α/[°] safety coefficient Fs 1 10.55 5.5 37 28 1.519 2 10.55 11 47 33 1.621 3 10.55 16.5 57 38 1.695 4 21.10 5.5 47 38 1.224 5 21.10 11 57 28 1.574 6 21.10 16.5 37 33 1.223 7 31.65 5.5 57 33 1.417 8 31.65 11 37 38 1.043 9 31.65 16.5 47 28 1.343 Table.4 Range analysis of each parameter parameter density γ/[kN·m³] cohesion c/[kPa] angle of friction φ/[°] angle of slope α/[°] K1j 4.835 4.160 3.785 4.436 K2j 4.021 4.238 4.188 4.261 K3j 3.803 4.261 4.686 3.962 Rj 1.032 0.101 0.901 0.474 sensibility density > angle of friction > angle of slope > cohesion Conclusions Force-displacement curve obtained from the push-shear test of granular gangue presented the characteristics of complete stress-strain curve, which caused obvious strain softing.

Because according to the Hall-Petch equation, the strength properties of the material rise along with the reduction of the grain size.
In case of the coatings deposited by the PVD and CVD processes, the structures obtained, with grain size ~10 nm cause the obtainment of the maximum mechanical properties.
The produced coatings reveal a number of microparticles in the form of droplets occurred in the structure.

These methods allow growing multicomponent films having an arbitrary number and composition of elements with only one magnetron employed.
The small individual grains were appeared for all of the substrate-to-target distances.
The small grains with triangle shape spread across the surface were investigated for all substrate-to-target distances.

In addition, adding nano-Y2O3 particles promoted the formation of equiaxed grain, due to Cr23C6 and nano-Y2O3 act as heterogeneous nucleation sites in the melting pool.
The large number of easily sheared hcp {0001} planes, which were found parallel to the wear track surface, can be regarded as an explanation for the low friction properties of the laser processed Co-based alloy [16].
It was reported that, Dendrite microstructures were observed perpendicular to the interface of each layer where coarsening of microstructures were obtained as more layers are deposited; at the bonding zone of two layers, equaxied grain appeared locally.