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Chart 1 Correspondences for five factors and two levels Factor Level A （Cementitious material） B （Admixtures） C （Coarse aggregate） D （Fine aggregate） E （Cementitious material） 1 Aluminate cement CA-50 Slag [3] Gravel（Continuous grain size 31.5） Mechanical sand（Fineness modulus 1.64） Naphthalene（HZ-7 Superplasticizer） 2 P.O42.5cement Fly ash[4]（Ⅱgrade） Ceramic（Continuous grain size 5-19） High aluminum powder （Ultrafine powder）:Fine ceramic Polycarboxylate （HT-HPC Superplasticizer） Chart 2 Orthogonal experiment chart for five factors and two levels Factor Level Number of trials Cementitious material Blended admixtures Coarse aggregate Fine aggregate Admixture 1 1 1 1 1 1 2 1 1 1 2 2 3 1 2 2 1 1 4 1 2 2 2 2 5 2 1 2 1 2 6 2 2 2 2 1 7 2 1 1 1 2 8 2 2 1 2 1 Chart 3 Experiments record for the performance of heat-resistant concrete admixture Number of trials Quality mix ratio（cement:water:coarse aggregate: fine aggregate:blended admixture:admixture） 1 300:
According to the number of test project, every test includes 18 standard samples, and 144 standard samples for all.
Chart 4 Test record for the mechanical properties of concrete（MPa） Test number 7d Standard curing strength 7d after standard curing 900℃constant temperature 24h strength 28d Standard curing strength 28d after standard curing 900℃ constant temperature 24h strength 1 18.3 16.1 28.4 15.6 2 17.6 16.2 27.6 20.2 3 16.2 15.1 27.9 20.6 4 18.3 16.1 28.4 25.2 5 19.1 16.4 30.5 19.8 6 17 16.1 27.1 23.7 7 19.8 16.5 29.8 15.3 8 16.6 12.6 26.4 18.5 4.1 the range analysis for 7d Standard curing strength It can be seen from Chart 4 and Figure 1 that, for the two factors of A and E(that are cementitious material and admixture), the maximum value between the two levels are K2, for the three factors of B, C and D(that are blended admixture, coarse aggregate and fine aggregate), the maximum value between the two levels are K1.
For coarse aggregate, under the condition of 7 days standard curing, gravel (continuous grain size 31.5) was better, and under the other conditions, ceramic was better.
Based on the concrete strength after 28 days standard curing at the constant temperature of 900℃ for 24 hours, in the range of materials can be selected, the most suitable materials are: aluminate cement CA-50, fly ash(Ⅱgrade), ceramic(continuous grain size 5-19), high aluminum powder(ultrafine powder), fine ceramic and polycarboxylate(HT-HPC superplasticizer). 2.

The number of the scale levels involved in the consideration are due to the study aims and objectives and real mechanisms of the inelastic deformation.
The paper investigates the two-level model of the inelastic deformation: a meso-level element is an individual crystallite (grain or phase), a macro-level element is a representative volume of the polycrystal sufficient for statistical averaging of the crystallites set.
According to this hypothesis, the gradient of the displacement velocity for each crystallite coincides with the gradient velocity of the macrolevel : where N is the number of crystallites within the representative volume.
Here o is the tensor of the actual grain crystallographic coordinate system orientation with respect to the fixed laboratory coordinate system; 7 is the viscoplastic relation for the shear rates of k-th slip system, - the shear stress of k-th slip system, ΔG is the activation energy of the dislocation slip; 8 is the relation for temperature rate.
McQueen, Grain and subgrain structures developed by hot working in as-cast 434 stainless steel, High.

Results and discussion Cast steel solution heat treated in water features a two-phase structure with austenite grains distributed in the ferritic matrix.
The microstructure (a) and diffraction pattern (b) of the investigated cast steel after the annealing 800°C/10h It shall be emphasized that ferrite decomposition as a result of heat treatment proceeds unevenly in the grains volume and starts in boundary areas of primary δ-ferrite grains, what is illustrated in Fig. 3.
Higher temperature causes origination of smaller number of nuclei and higher diffusion rate favors higher enrichment with chromium and molybdenum.
After annealing at 700°C the σ-phase featured the highest dispersion, proven by: the highest number of particles Li=0.183µm-2, and their smallest average area A=3.2µm2.
The decrease in particles number at 900°C as against 800°C (Tab. 2) is determined by a significant decline in σ-phase volume fraction and not by reduced dispersion.

The number of closed pore in the metal foam produced were increased with the increasing of SS316L composition.
The transition from SS316L particle to grain occurs when the particles sinter-bond, forming a structure consisting of many grains.
Almost all of the micropores were found at the grain boundaries.
Grain boundaries Figure 6.
However, the number of closed pore in the microstructure should be minimized.

It is caused by the precipitation of the chromium rich carbide such as Cr23C6 along the grain boundaries and lead to chromium depleted zones at the grain boundaries.
It is again due to the grain boundaries attack and chromium precipitation in specimens that undergo sensitization.
During the carbide precipitation, interstitial carbon diffuses rapidly to the grain boundaries.
Slower diffusion rate of the chromium results in the chromium depleted zones at the grain boundaries.
General corrosion with no grain boundary corrosion or cracking can be seen for the solution without H2SO4.

To ensure high and reliable mechanical properties of WC-Co cermets, the WC grain size must be fine and uniform distribution [3].
In this study, the specimens with a 2-3 μm grain size are designated as “G5” hereafter, and the specimens with a 0.5 μm grain size will be designated as “F12”.
In addition, compared with the G5 and F12 specimens, the smaller grain sizes possess a greater area fraction of grain boundaries along the line of the mobile dislocations.
Therefore, the number of dislocation tangles was greater, which strengthened the hardness.
The fine grain size cannot easily generate the liquid phase β-Co (WC) gathering phenomenon.

Indeed, matters of technique and associated statistics are also an issue for the basic measurement of grain size.
EBSD allows grain sizes to be defined in many ways, especially in part-recrystallised or intercritically-rolled material.
A sufficiently large area of examination to match that of a standard optical assessment is still time-consuming, but no one set of conditions or definition of a grain reliably reproduces the optical grain size.
The pilot and laboratory data are built up on wider composition and processing ranges than is possible from production, assisting the establishment of tendencies which would be much harder to spot from the tightly-grouped pockets of mill data, albeit of much higher numbers of rollings.
Kundu et al, in: 4th International Conference on Recrystallisation and Grain Growth, Sheffield, UK, 4-9th July 2010, publ.

To reveal the alpha grain structure on the joint surface, an etching process was performed using a 2% Nital solution.
At higher temperatures, microhardness increased, indicating potential diffusion and recrystallization of zinc grain structures, resulting in finer grains upon rapid cooling.
The slow approach to the eutectic point of pure zinc solid at 60°C facilitated potential diffusion or recrystallization of zinc grain structures, resulting in finer grains during fast air cooling.
Acknowledgement This research was supported in part by the from grant number: SEGiIRF/2022-Q1/FoEBEIT/001. 6.
Mahapatra, Prior-austenite grain refinement in P92 steel using double austenitization treatment, Mater.

Apart from the requirement of heat resistance, bond of carbide should also meet other requirements for the appropriate level of cobalt bond properties, including: ∙good wetting properties of carbide grains; ∙low carbide-forming ability; ∙sufficientductilityproperty.
The technology allows: • effectively inhibiting coagulation of grains at sintering temperatures; • increasing density and uniformity of carbide components in terms of replaceable multifaceted insert (RMI); • ensure uniformity of carbide grains (WC, TiC, TaC) in size and shape [1,2,11].
It is also very important that rhenium retains a high level of properties at elevated temperatures and meets the number of requirements to alloying elements  it does not form stable carbides, and, when interacting with cobalt, it forms a continuous series of solid solutions.
Composition and properties of carbides of VRK group Grade лавасплава Composition Bending resistance,kgf/mm2 Hardness, HRA Microstructure of carbide WC,% Re,% Со, % Total porosity, % volume Number of grains up to 1.0 μm, % VRK-12 88.5 3 8.5 174.8 90.0 0.02 79 VRK-13 86.8 6 7.2 260.4 90.5 0.02 84 VRK-15 85 9 6 211.5 91.5 0.04 83 Studies of structure and properties of VRKcarbides have shown that they have high hardness and retain high strength at elevated temperatures, and cutting properties significantly exceed corresponding values of tools of VK10-OM and VK10-HOM carbides recommended for machining of heat resistant alloy (ISOS10-S30).
Thickness of sublayers of intermediate TiN-layer also reaches about 15-25 nm, and its grain size, like grain size of adhesive sublayers, does not exceed 5-15 nm.

In order to facilitate the description, the joint is divided into three zones, as shown in Fig. 3, where the joint was composed of non-isothermally solidified zone(region Ⅰ), isothermally solidified zone(region Ⅱ) and diffusion affected zone (region Ⅲ). Ⅰ a b Ⅰ Ⅱ Ⅲ Ⅲ Ⅱ c Ⅲ Ⅱ Fig. 4 Microstructure of joint in different bonding temperature, a 950℃, b 1000℃, c 1050℃ For isothermally solidified zone, with the increase of bonding temperature, the width of region Ⅱ increased from about 10μm to about 80μm and finally to about 110μm when the bonding temperature is 1050℃, the microstructure of region Ⅱchanged from large irregular white grains (Ti(Cu,Al)2) to solid solution in the shape of a crack (Nb(Cu,Al)) in the white matrix, And the width of region Ⅰ decreased from about 69μm to about 23μm and finally disappeared when the bonding temperature is 1050℃, the microstructure of region Ⅰ changed from of gray and white solid solution of obvious grain boundary (AlNb2) to black flocculus
It can clearly reveals that with the increase of bonding temperature, the microstructure of base metal changed from a large number of columnar grains (B2 and O phase) to many formation of recrystallization grains( β and small number of α2 ) in the base metal when the bonding temperature is 1000℃, and there is many dendrites formed in the base metal.
With the bonding temperature increase, the boundary between region Ⅱ and region Ⅱ became fuzzy,and the microstructure of region Ⅲ changed from light black flocculus to the diffusion of light black flocculus which has more recrystallization grains when the bonding temperature is 1000℃, and more dendrites were formed when the bonding temperature is 1050℃.
Fig. 6 XRD patterns of different bonding temperature b 20μm Ⅰ Ⅱ Ⅲ a d 10μm Ⅰ Ⅱ Ⅲ c f 20μm Ⅱ Ⅲ e Fig. 7 SEM images of the joints TLP bonded under different bonding temperatures (a) and (b) bonded at 950℃, (c) and (d) bonded at 1000℃, (e) and (f) bonded at 1050℃ The morphology of joint shown in Fig. 5a was obviously different from other two as shown in Fig. 5c and Fig. 5e, and there were many light gray and black grains in the middle of the joint, and the grain boundary is obvious.
And most secondary phases in the joint are located in the middle region of the joint, only a small number of secondary phases appeared in the isothermally solidified zone in the shape of a crack, and the proportion of secondary phases in the joint is 20.2%.