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With the increase of the number of atoms in the crystal cell, the equilibrium lattice parameters of each crystal structure also change, showing different change trend.
The number of candidate materials can be calculated as C (32,6) =906192, which is 106.
Due to the number of 106 grade candidate samples generated in high-throughput doping calculation of copper alloys, a lot of computing resources and time are needed.
As shown in the figure below, the initial structure count is 30, the maximum count is 10 each time, and the loop cross validation number is 0.02.
Gavriljuk, On a mechanism for enhanced hydrogen flux along grain boundaries in metals, Acta Mater. 194 (2020) 516–521.

Introduction Small precipitates can substantially increase the strength of a material, since their presence hinders dislocations and grain boundaries from freely migrating through the microstructure.
Some of the parameters of major importance for precipitation hardening are the size, number and distribution of precipitates as well as their long-term stability.
In the last two decades, computational thermodynamics based on comprehensive databases for a number of different materials has been employed with great success to assist the development of optimum production routes [1].
The model In the new model, a unit cube of matter is considered, which contains an arbitrary number of precipitates of different type, chemical composition and size.
If a positive J is calculated, a number of J∆t of new precipitates is created and added to a list of existing precipitates.

A number of steady motes are in a high speed movement, and collide with each other in all probability.
The product of this solid-state process is usually a number of non-equilibrium phases [11].
In another work, Delogu [3, 4] demonstrated that decreasing the average grain size during mechanical alloying increased diffusivity.
The existence of the large number of nuclei in solution provides a mass of crystal growth cores for combining each other.
Large numbers of congener nuclei congregate at cathode substrate so as to deposit.

In recent years, many researchers at home and abroad make a number of experiments and theoretical analysis on structural performance of steel fiber reinforced shotconcrete[1-6].Among them, Professor Du Guoping researches the enhancement mechanism of steel fiber reinforced shotconcrete from the viewpoint of its mechanical property [7] ; Professor Liu Xin carried out experimental study of basic mechanical properties of steel fiber reinforced shotconcrete from the viewpoint of this actual work [8]; But the research about the influence on concrete micro pore structure under different construction technology is still small.
In this paper, we do experiments on pore structure of steel fiber reinforced shotconcrete , use mercury intrusion method to test pore structure ,analyse and compare effect on concrete matrix pore structure with sprayed build and model build , and then from the microscopic point of view, analyze the effect on the mechanical properties and durability of steel fiber reinforced concrete under thus different construction technology. 2 raw materials and test methods. 2.1 raw materials Steel fibers used as shear waving steel fibers, produced by Chongqing Yizhu Trading Company , slenderness ratio is 60, tensile strength is greater than 500 MPa; Huaxin cement 42.5R ordinary portland cement is used to meet the requirements; coarse aggregate used machine processed gravel at the scene of the tunnel,for the Crossing site mechanism gravel, grain diameter is 6.0 ~ 10.8 mm continuous grading ; fine aggregate used compound with machine processed gravel and Yichang middle-thick river sand at the scene
Admixtures used highly active alkali-free liquid accelerating agent and highly active water reducing agent produced by Germany BASF corporation; ganister sand uesd silica fume produced in Chongqing, the average grain diameter is 0.1 microns; mixing water used on-site drinking water. 2.2 test method The commonly used gaging pore methods are of optical microscopy, electron microscopy, mercury intrusion method, adsorption methods, X-ray small angle diffraction method and so on.
Based on the pore distribution curve of mercury intrusion test, is the quantitative characterized form between pore diameter of steel fiber reinforced concrete and pore size, number.The curve is a cumulative distribution curve, can visually and quantitatively show the composition and distribution of pores, as Figure 2.Table 4 in which the critical pore size is defined as the amount of mercury pressed into the corresponding significant increases of steel fiber reinforced concrete maximum pore size; most probable pore size refers to the corresponding peak value of pore size.

Test condition of wear resistance are as follows: the abrasive grains are 40 purpose, the most-positive pressure is 23kg, the standard speed is 240r/min, testing time is 5 min, the size of the sample is 10mm×20mm×60mm .
Table 2 Heat treatment processes Serial number Heat treatment processes Process one Process two Process three Process four Diffusion annealing+880℃×2h×oil quenching+180℃×2h×air cooling Diffusion annealing+880℃×2h×oil quenching+220℃×2h×air cooling Diffusion annealing+880℃×2h×oil quenching+260℃×2h×air cooling Diffusion annealing+880℃×2h×oil quenching+500℃×2h×air cooling Results and Analysis Microstructure and Hardness at Cast and Diffusion Annealing States.
Without any indication of brittle flake or the form of loose sediments of multiple carbide and WC ceramic phase,there is a large number of parallel cutting grooves, and the grooves orientation are identical basically, no present the transverse or oblique furrows, showing that the surface hardness is large under the process, wear sands cannot transverse or oblique cutting, wear-resisting performance is better.
The wear resistance is higher with tempering sorbite + WC grains dues to the evenly distributed carbide particles between the short ferrite lath bundle skeleton matrix in the tempered sorbite, The fatigue crack is not only hampered by ferrite phase interface when extending from surface layer to the surface during wear process, but also occurs plastic deformation, which makes the crack tip stress relaxation and inhibits the extension [15].

Constitutive equations At the grain level, the plastic strain rate is given by the sum of the shear strain rates from all the active slip systems , (3) where N is the number of slip systems, is the Schmid tensor of the slip system .
Stable multi-junctions can undergo a maximum number of three serial higher-order non-coplanar interaction types during deformation.
Self-consistent polycrystal models: a directional compliance criterion to describe grain interactions.

Since a number of reports about friction stir incremental forming are not so many and most of them are presented by the authors’ group, results about friction stir incremental forming by the authors’ group are introduced in this paper.
Area of occurring dynamic recrystallization and grain refinement by friction stir incremental forming is considerable to be limited to certain depth from the surface.
AZ80 sheet was thicker and the effect of dynamic recrystallization and grain refinement on the improvement of formability was smaller than those of AZ31 ones.
Acknowledgement Researches introduced in this paper are financially supported by JSPS KAKENHI Grant Number 22360309 and 25289261, and Cross-ministerial Strategic Innovation Promotion Program from Japanese government.

It is considered that the interface between powder boundaries cannot be eliminated immediately after establishing contact, and a certain number of micro-voids formed by the particle surface roughness are located on this interface.
Interface source diffusion follows one of the two routes as indicated in Fig. 2(b), addressed respectively as grain boundary diffusion (along the interface) and volume diffusion mechanisms.
Table 2 Sample Information Extracted from Subroutine in Abaqus Displacement Node Number Radius (r) Contact Pressure [MPa] Micro-void Radius [µm] Diffusion Bonding Parameter … 2.00 A 0.00 48478 0.0075 0.85 … 2.00 B 1.47 38737 0.0288 0.42 … 2.00 C 2.09 27433 0.0466 0.07 … Summary In this paper, the concept of interfacial bonding in powder forging was introduced, and a numerical diffusion bonding (DB) model was developed for a new powder forging technique, direct forging (DF).
Johnson, New Method of Obtaining Volume, Grain-Boundary, and Surface Diffusion Coefficients from Sintering Data, J.

Already by mortars preparation stage, the short fibers are uniformly dispersed and mixed with the very fine dry solid cement and aggregates grains, leading to the production of a homogeneous mixture and finally mortar.
Materials The cement type used was CEM IV 32.5 N and fine limestone aggregates were of 4mm maximum grain (sand).
Table 1: Compositions of mixtures composition codes (the number reveals the % fiber volume percentage) constituents M0 M0.25P M0.50P M0.75P M01.0P M1.25P M1.5P M1.75P M2.0P cement IV 32.5N [g] 1500 1500 1500 1500 1500 1500 1500 1500 1500 fine aggregates [g] 500 500 500 500 500 500 500 500 500 PP fibers [g] 0 2.3 4.6 6.8 9.1 11.4 13.7 15.9 18.2 admixture [g] 3 3 3 3 3 3 3 3 3 water [g] 300 300 300 300 300 300 300 300 300 For each composition three molds for rectangular specimens of dimensions 40mmx40mmx120mm were casted.
Li and his collaborators showed that fiber-matrix interface debonding energy could play important role in their toughening mechanism, even though a large number of possible crack mechanisms could arise [7].

However a comparison of the microstructures shown in Fig. 2 shows that as the PWHT time increases, there is an appearance of grain boundary carbides away from the pearlite zones and these carbides coarsen as the PWHT time increases further.
There also exist now a number of reasonably robust correlations between Charpy results and fracture toughness for use in the upper shelf region [11].
This is borne out by the metallographic examination, which showed an increase in the formation of grain boundary carbides and a gradual increase in the size of these carbides as the PWHT time increased.
This could be due to a number of reasons.