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The growth of strain-free grains is simulated using the mis-orientation angle dependent grain boundary energy and interface mobility.
The cumulative number of activated slip systems is then computed at each time step throughout the simulation.
Areas with a cumulative number of activated slip systems higher than a critical value in the deformed microstructure are assumed to be nucleation sites for the subsequent static recrystallisation.
A linear interpolation method reported in [24] has been chosen to map the data, such as the number of activated slip systems, grain orientations and stored energy from the CPFE model to the PF model.
As for recrystallisation, the nucleation sites have been simulated using the ODR theory by comparing the cumulative number of slip systems activated during the previous deformation with a critical value.

Introduction The necessity to produce lightweight components in an increasing number of industrial sectors is an important driving force for introduction of magnesium alloys.
One can also note that a way to increase the efficiency of ECAE processing is to reduce the temperature of processing with the number of extrusions.
From relation (2), one can predict the critical grain size for which, at a given temperature, grain boundary diffusion dominates.
At 350°C, a grain size of about 10 µm is predicted.
This increase was preferentially attributed to strain induced cavity nucleation rather than cavity growth since the mean cavity diameter remained roughly constant whereas the number of cavities per mm3 noticeably increased [14].

The TiC0.3N0.7 grains in preforms deposited on three kinds of substrates all took on anomalous equiaxed grains.
The grain size of them was all less than 3μm.
When with 45 steel as substrate, it took on near equiaxed grains.
During the metal spray forming process, the cooling rate of metal droplets was usually in the number order of 106℃/s[6-8], which was lower for one number order than that of the reactive spray forming process.
The growth of TiB2 grains along the c axis has been limited, which made it hard to form rod-like grains structure.

After refinement and outlier rejection the final number of reflections per grain was ~90.
The number of grains that can be mapped simultaneously is limited by the extent of peak overlap, which is more severe for textured and/or deformed materials.
Between 248 and 329 grains were indexed and refined in each layer, and after refinement and outlier rejections the final number of reflections per grain was ~55.
The reason for this can be found in the number of assigned reflections per grain, which is 90 for IF steel because the grains were allowed to compete for multiple assigned reflection, compared to 55 for Cu where all multiple assigned reflections were rejected.
The approach has proven to be superior in performance with respect the number of grains that can be mapped and the accuracy to which the grain resolved properties can be determined.

The nano-sized grains of ~300 nm were obtained after 8 ECAPs at 373 K and 473 K.
Introduction A number of research studies have been recently attempted to obtain the nano-structure in metallic materials by imposing severe plastic deformation (SPD) such as equal channel angular pressing (ECAP), accumulative roll bonding (ARB) and high torsion pressing (HTP), etc [1].
The starting materials showed the average grain size of approximately 200 �.
Near equiaxed nano-sized grains of ~300 nm was introduced by 8 ECAPs at 373 K and 473 K, although the grain size at 373 K was slightly smaller than that at 473 K.
However, in case of pressing at 473 K, the improvement Journal Title and Volume Number (to be inserted by the publisher) in strength was found without sacrificing much of elongation.

Meanwhile, a set of optimal craft parameters for preparing Co3O4 nanoparticles with smaller grain diameters was propounded and the effect of four process parameters mentioned above on grain diameter of resultant was figured out via 3D diagrams.
By maximizing it, the array w can be written in terms of the Lagrange multipliers and training samples as: (8) where, l is the number of SVs.
, itermax is total number of iterations.
In Table 1, each value in last column entitled Y is given by subtracting the value of grain diameter from 100nm.
It is found from Fig. 2 that the grain diameter is relatively larger under a higher concentration of Co(NO3)2 solution, in other words, the high concentration of Co(NO3)2 may result in agglomeration and grain diameter growth.

Ga Penetration along the Grain Boundaries of Aluminum Alloys.
The Ga penetration process along grain boundaries of Al-based alloys while they are in contact with Ga containing aqueous solution was studied.
Currently, several known systems, in which the effect of fast penetration of liquid metal at the grain boundaries were observe are: Copper-Bismuth (Cu-Bi), Nickel-Bismuth (Ni-Bi), Aluminum-Gallium (Al-Ga).
The effect of embrittlement can be interesting as a method of preparation for grain boundary (GB) chemical composition study.
Acknowledgement This study was carried out with financial support of Ministry of Education and Science of Russian Federation (Co. 4.1963.2014/K) and Russian Foundation of Basic Research (Project 13-03-12191) with the use of the equipment of Common-Use Scientific Center‘‘Material Science and Metallurgy’’ at NUST ‘‘MISiS’’ (identification number RFMEFI59414X0007, agreement № 14.594.21.0007) References [1] R.S.

The present study aims to examine the tribological characteristics of the ultra-fine-grained dual phase steel.
The grain size of the ferrite grains is ~20 µm and the pearlite grains with the size of ~10 µm are distributed relatively randomly.
The microstructure of the ECAPed low carbon steel which is characterized by UFG ferrite grains with high density of lattice dislocations, subdivided pearlite colonies, and a large number of boundaries with extrinsic boundary dislocation [5] is suggested to provide the uniformly distributed austenite nucleation sites, and to accelerate the partitioning kinetics of carbon and manganese, which resulted in the uniformly distributed martensite islands along with equiaxed ferrite grains.
The martensite islands also restrained grain rotation, which impeded the coarsening of ultra-fine grains.
It is reported that the grain boundaries of the severely deformed monolithic materials are so unstable that coarsening of the ultra fine grains easily occur during wear, which results in high wear rate in spite of their high hardness [6].

The material subjected to forward/forward deformation did, however, have a slightly greater number of low angle boundaries, i.e. boundaries < 15° misorientation, whilst the forward/reverse material had some grains containing little evidence of substructure.
On annealing both materials had significantly reduced levels of low angle boundaries but only the forward/forward material had an increased number of high angle boundaries and a reduced grain size, indicating recrystallisation had only occurred in this material.
For the F/F material all grains have a significant substructure, whereas for the F/R reverse material there appears to a more bimodal distribution of grains with some having high levels of substructure and other grains having virtually no substructure.
Grain sizes for material as-deformed and annealed for 1 hour at 400°C Test Deformed grain size (µm) Annealed grain size (µm) 0.25F/0.25F 42 28 0.25F/0.25R 60 62 conditions the number of low angle boundaries is quite similar with there being at most 10% more boundaries for the F/F case.
For both the F/F and F/R cases there is significant substructures developed but there is a slightly reduced number of low angle boundaries for the F/R as well as some grains with little or no substructure This in turn has a dramatic influence on recrystallisation response with no evidence of recrystallisation in the F/R material whereas the F/F is completely recrystallised.

The dressing progress is quantified by the cumulative collision number id, representing the number of collisions of the engineered grinding wheel grains with the abrasives of the dressing wheel [9].
The specific force values show a linear trend for all grinding wheels due to the increasing collision number id during the dressing process.
Additionally, the surface roughness values Sa and Sz show a clear correlation to the collision number id of the Engineered Grinding Wheels.
The surface roughness decreases with increasing collision number id because the cutting mechanism turns into ductile removal (figure 3, right).
In comparison, the surfaces ground with conventional diamond grinding wheels show a high number of outbreaks.