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Related studies [6,7] have shown that adding element Nb can serve as a stable phase NbC to improve the strength and hardness of material, can be also used as grain refiner to inhibit TiC particles growth.
As clearly visible in the SEM micrographs, the coatings consist of compact grains, little porosity and cracks.
Otherwise, (Ti,Cr,Nb,Mo)xCy solid solution formed by adding Nb, Cr and Mo to TiC, which can improve the plasticity, toughness and inhibit grain growth [6,7].
While (c) and (d) show that the number of cracks and other defects are significantly reduced, the organization is relatively dense and the material uniformity is well improved.
The coatings consist of compact grains, little porosity and cracks.

Owing to the non-ferrous metals and their alloys possess a number of special performances that steel material does not have.
Testing medium is dry quartz sand (grain size 3.0-5.0 mm).
Fig.3 Abrasive mass loss of Q235 steel, pure Al and Al-Mn alloy coatings With regard to the obtained results, Manganese is an important factor influencing resistance.It can be discussed in two sides. 0n one side, the dispersive- distributed MnAl6 compound can significantly inhibit the growth of the grain, thus to refine the grain and to achieve the fine grain strengthening.

Damage of the facet represents the crack-growth through the cement matrix and interfacial transitional zone between two grains.
The remaining parameters of the deterministic model were not reliably determined, because the available information was not sufficient; due to this fact, parameters like the elastic modulus Ec and parameter α determining the macroscopic Poisson’s ratio, were identified from the elastic part of l-d curves or calculated according to relationships from [2] (elastic modulus of grains Ea, shear strength fs, fracture energy in shear Gs, compressive strength fc and other).
Parameters of the deterministic model were kept constant during all simulations; the only source of variability was in random positions of grains.
CMOD [mm] The parameters for the stochastic extension of the model were determined in two steps: firstly, the coefficient of variation of 14 % was evaluated based on a fitting procedure applied to a group of beams with the deepest (group Ba with the highest number of realizations).
The deterministic version of the model (which contains randomness due to the random locations of the largest concrete grains) explains a large portion of variability measured in the experiment.

Introduction By means of the technique of surface mechanical attrition treatment (SMAT) [1], the nanocrystalline and submicron-sized grains may be obtained in the treated surface of bulk materials.
As for the severe plastic deformed material, both strain and strain rate had a gradient variation from the treated surface (both are extremely large) towards the deep matrix (essentially zero), and as a result, the grain sizes with gradient distribution were developed in the treated samples [2].
There is a successive grain refined microstructure in Fe [3], Cu [4], Al-alloy [5], and stainless steel [6] etc, leading to enhanced mechanical properties.
Annealed (at 1173K for 1h) 2.8mm thick plates with a grain size range from 10µm to 30µm were prepared for the SMAT.
In the SMAT in the present work, a large number of hardened steel balls of 8mm in diameter were placed at the bottom of a cylinder shaped chamber that was librated by a generator, with which the balls were resonated and to peen the sample surface to be treated at the upper side of the chamber.

A two peak thermal cycle, as shown in Fig. 1, was applied to each smooth rectangular specimen sampled from the plate, and the thermal cycle simulated the inter- critically reheated coarse grained HAZ in offshore structures　[6].
Its prior-austenite grain size was about 200μm, and precipitates were recognised along prior-austenite grain boundaries and bainite lath boundaries.
The area of the tensile sections in micro-sized specimens is smaller than that in macro-sized ones, and the number of grain boundaries and precipitates, which can be the resistance to dislocation movement, probably affected σys and σts in the specimens.

The matrix grain boundary is clear.
Aging state(see Fig. 2c), the grain is fine and the microstructure is more uniform.
After solution treatment (see Fig. 3(b)) and aging treatment (see Fig. 3(c)), the original cast of the rare earth phase mostly dissolved into the matrix, the cleavage steps in the alloy increases, the number of tearing edges is reducing, and alloy shaping has improved.
In the as-cast Mg-9Gd-4Y-0.5Zr alloy, the grain size is coarse and the distribution of precipitates is not uniform.
After solution and aging treatment, most of which dissolved into the matrix, the grain size became smaller and the microstructure is more uniform. 3.

Secondary phases, introduced to improve sintering, have become increasingly important in controlling the average grain size and grain-size distribution of the major phase.
On the other hand, the highly anisotropic materials like Al2TiO5, showing grain boundary microcracking in polycrystalline bodies have extremely low strength [6].
Microstructure and grain size studies were performed by Scanning Electron Microscopy (Phillips 515).
The thermal shock resistance was determined through the number of reversals of heating at 900o C followed by rapid cooling in water.

The grain size of the CuInSi film increases as annealing temperature.
In this work, the average grain size is about 15.5 nm .
The surface topography of the as-deposited layer is not uniform and the grain size is a few hundred angstroms.
After annealing, the topography has been changed considerably and an apparent increase in grain size is clearly seen.
The energy gap (Eg) of CuInSi film was calculated based on the following equation[8] (2) where A is a proportionality constant, h is the Planck constant and n is a number which characterizes the transition process, n=1/2, 2, 3/2 or 3 for allowed direct, allowed indirect, forbidden direct or forbidden indirect transitions, respectively.

As can be seen from the pictures, some dense particles without regular shape were found on the surface of CrN coatings with the nitrogen flow percentage of 30% and 40%, but the grain size was smaller with the nitrogen content of 40%.
Besides, the plane grains perpendiculared to the pyramid particles and co-existed with the pyramid particles was also found in the surface morphologies of CrN coatings, which might be the cause of the CrN (220) orientation.
In addition, the plane grains strengthened the density of CrN coatings and the number of plane grains is larger with the nitrogen content of 60%.

After grinding with the pre-dressed wheel begins, the grains are worn and the insulating layer on the wheel surface is removed (�,�).
Dressing started Dressing completed Process started Process stabilized (Hydroxide, oxide) Fe ions Protruding grain Worn Oxide layer removed Contacted Scraped oxide Chip Flat face After Truing 2+ Insulating layer 1 2 3 4 5 Dressing started Dressing completed Process started Process stabilized (Hydroxide, oxide) Fe ions Protruding grain Worn Oxide layer removed Contacted Scraped oxide Chip Flat face After Truing 2+ Insulating layer Dressing started Dressing completed Process started Process stabilized (Hydroxide, oxide) Fe ions Protruding grain Worn Oxide layer removed Contacted Scraped oxide Chip Flat face After Truing 2+ Insulating layer 1 2 3 4 5 Fig.1 ELID grinding flow chart Experimental Method Experimental system Fig.2 shows the cylindrical grinding machine with ELID system.
Conclusion In this study, we have made a number of differently shaped micro tools and micro structures using cylindrical grinding with ELID.