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In recent years, a number of papers have been published on the fracture properties of laminated composites, and illustrated that laminated metal composites are especially effective in improving fracture-related properties by various extrinsic mechanisms [7, 8].
Intrinsic toughening mechanism implies in-situ resistance of the microstructure (precipitates, particle spacing, grain size and morphology, etc) on crack propagation.
In addition, the two laminated Ti-TiBw/Ti composites reveal an interesting gradient grain distribution as shown in Fig. 1b): lath-like grains in the Ti layer, fine equiaxed grains in the zone of the TiB whisker, and small lath-like or near equiaxed grains inside of network structure.
Gradient grain distribution and enhanced properties of novel laminated Ti-TiBw/Ti composites by reaction hot-pressing.

The traditional methods for setting up an experiment generally involve description of all variables among observed correlated variables in terms of a potentially lower number of unknown variables, so-called factors.
The results obtained suggest that the minimal grain size is obtained in an arc welding operation at the current strength ICS=240-260 А and the arc voltage UA=28-30 V (Fig. 1).
The microstructure is composed of polyhedron grains alternating with groups of short misoriented dendrites.
In sample 4 there are areas free from dendrites; however, no grain boundaries are discernible.
Addition of nanostructured powders causes grain refinement of the surfaced metal (42 % and 33 % reduction in grain thickness and width is attained, respectively). 5.

It has been suggested that the high density of dislocations and grain boundaries can provide the rapid diffusion channels and also the adiabatic heating during deformation might increase the diffusion of carbon from cementite.
The number of cracks increases up to strain of 1, however increasing strain more than 1 decreases the number of cracks.
It has been proposed that cracks initiate in a material under strain and stress due to condensation of vacancies in the grain boundaries and some lattice defects like dislocations [14].
The supersaturation of the lattice defects and the vacancies in grain boundaries occur during the rapid deformation process in high temperature.
The quenching at lower temperature or lower undercooling also decreases the supersaturation of vacancies in the grain boundaries and the dislocations, which can explain the reason for the absence of crack formation in the sample when quenched at lower temperature.

However, the industrial use of SPF is still limited because of a number of issues that have been hampering its widespread use.
Constitutive Model For viscoplastic deformation, the general associative flow rule is given by [7, 8]: σ J f ∂ ∂ = p D (1) where: /m p J d k f 1 = , 123 κIJJ += , S.S 2 1 2 =J where pD is the plastic strain rate tensor, f the overstress function, ( )σJ is a positive scalar-valued isotropic function having the dimensions of stress, σ is the Cauchy stress tensor, m is the strain rate sensitivity, k is a material constant, d is the grain size, p is the grain size exponent, κ is a function of the area fraction of voids, and 1I and S are the first invariant and the deviatoric part of the Cauchy stress tensor, respectively.
The grain growth model used in this work has the following form [9]: εcdd += ° (3) where dο is the initial grain size, ε is the effective strain, and c is a material constant.
To verify this observation using FE analysis, a number of simulation runs are conducted.

Wang et al. [4] simulated a hot rectangular shaped ring rolling process of Ti-6Al-4V alloy and claimed that with the increase of the initial temperature of ring, the distributions of β phase and its grain size become more uniform but the volume fraction of β phase and grain size increase.
Zhu et al. [5] simulated a hot rectangular shaped ring rolling process of TA15 alloy and declared that with the increase of the initial temperature of ring, the grain size distribution of primary α phase gradually becomes uniform; the distribution of primary α phase becomes more uniform at first and then less uniform.
Sun et al. [7] analyzed hot rectangular shaped ring rolling process of AISI 5140 steel and draw the conclusions that the distributions of the dynamic recrystallization grain size and the volume fraction of recrystallization become less uniform with the increase of the initial temperature of ring.
The number of mesh elements is approximately 8,000.
(1) (2) where is the average value of PEEQ, , is the PEEQ of element , is the total number of elements of conical ring, is the volume of element , is the average value of temperature, , is the temperature of element .

In the experimental part, compressive strength parallel to the grain will be investigated for specimens of artificially mineralized wood, because the parameter well correlates with other physico - mechanical properties [3].
Tests of compressive strength parallel to the grain were performed according to ČSN 490110 [1].
Minimum number of the specimens is 30 for one set (one species and one immersion time) test, totally 840 specimens were used for the experiment.
Numbers in parentheses are the standard deviations.
Compression strength limits parallel to the grain (1980)

As it was noticed above, safe exploitation of technical equipment depends of big number of factors, that is why such a main function extraction as “to develop the technical equipment safe exploitation of hazardous industrial objects” is logical.
Cracks are observed or on borders of grains in those places where large carbides М23С6 settle down in the form of chains (Fig. 3a), or in those places of a material in which there is a congestion of large carbides (Fig. 3b).
Morfologically the a-phase is generally present at various samples in the form of: 1) ferrite grains (least defected part of material); 2) fragmented ferrite; 3) defected ferrite (parts of material with high dislocation density and high bending-torsion of the crystal lattice) and 4) parts of material with microcracks.
The analysis of the big number of experiments has shown, that decrease of long durability, increase in term of equipment time operation of a ultrasonic superficial waves delay (SAW) increases.
On the other hand, growth of internal stress leads to increase in SAW delay time that is caused by ultrasonic fluctuations relaxation on sources of internal stress fields to which the grain borders are related, and fragments, particles of carbids on borders and inside of grains and fragments, microcracks.

The resulting microstructure of this air-cooled bainitic steel grade mainly consists of granular bainite morphology, which may be revealed by Light Optical Microscopy (LOM) and Scanning Electron Microscopy (SEM) as a semi-equiaxed ferrite structure and discrete islands of martensitic/austenitic grains (M/A constituent).
The bainitic ferrite grains are actually divided into bainite subunits only visible through Transmission Electron Microscopy [8].
The volume fraction of retained austenite was calculated from the integrated intensities of (111), (200), (220) and (311) austenite peaks, and those of (110), (200) and (211) for ferrite, using this number of peaks avoids possible bias due to crystallographic texture [10].
However, in spite of this bad EBSD performance, the higher number of as-austenite-indexed pixels in matrix might suggest a slightly more deformed austenite and a higher martensite volume fraction within the band.
The bainitic packet means, in this case, the effective grain controlling toughness, that is, the grain delimited by high angle boundaries (>15º) [11,12].

Introduction Equal channel angular pressing / extrusion (ECAP/ECAE) has been proved an effective severe plastic deformation (SPD) technique which can produce ultrafine-grained (UFG) bulk materials [1, 2].
During the pressing, the billet undergoes severe shear deformation but retains the same cross-sectional geometry so that it is possible to repeat the pressing for a number of passes not to lose the cross section [3].
Improved properties of the ECAPed materials which were due to the unique microstructure such as bimodel grains, large number of non-equilibrium grain boundaries, unusual texture, and et al. have increasingly been reported [2, 4, 5].
A second texture component which is stronger describes the grains oriented in the ND.

H.K.Tonshoff[4] studied the cutting force on single diamond grain and the connection between grain dimension, feed rate and feed stress; he considered feed stress is the main cutting force component, and feed stress increased with grain size increasing and decreased with feed rate adding.
Table 1 Experimental condition Workpice material Cooling type Feed speed Vf [mm/min] Diamond grain size (US Mesh) Common glass[30×30×12 mm] Dry cutting 50 10 Table 2 Experimental scheme Processing path Non-interference Adjacence Repeated Legend Track distance L[µm] ＞8000 200, 400, 600 0 Depth of cut ap[µm] 20, 30, 40, 50, 60 30, 40, 50 differential value of depth of cut: 10, 20, 30, 40 Experimental Results and Discussion Material Removal Process and Dynamic Characteristic with Path of on-interference.
AErms reduces with the decreasing of cutting force by observing figure 6, which shows that former groove cracks make for less material breaking of latter processing. 0 10 20 30 40 50 Force F (N)f 1 2 3 4 groove number 200um 400um 600um Cutting Condition:v =50mm/min, a =50um c p Material:Glass, h=908um 0.0200 0.0202 0.0204 0.0206 0.0208 0.0210 0.0212 0.0214 AErms(V) 1 2 3 4 groove number 200 400 600 Cutting condition:v =50mm/min, a =50um c p Material:Glass, h=908um Fig.5 Cutting force with different track distance Fig.6 AErms with different track distance Material Removal Process and Dynamic Characteristic with Path Repeated.