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The DSS base metal microstructure revealed an elongated grain structure, where austenite (g) phase is distributed in the ferrite (d) matrix with average amounts of 54% of ferrite and 46% of austenite.
The partially annealed region (HAZ2), adjacent to the base metal, is characterized by significant grain growth compared to the base metal.
The two weld metals structures are composed of ferrite and austenite; a structure of an interdendritic ferrite in austenite matrix structure is found in the E309 weld metal, while widmanstätten austenite grains within a matrix of ferrite is observed in the micrograph of the E2209 weld metal.
Fig. 8: Hardness variation across the X52 HAZ–WM interface The weld metals specimens reveal a ductile fracture mode, where a large number of dimples can be observed.

Several classic constitutive model of soil The number of soil constitutive model is much, but very few are used in practical applications to solve the engineering problems.
Building the constitutive model considering particle breakage Soil is the mixture of rock broken of weathering and mineral grains, the stress-strain relationship is complex, and related to many factors.
Salim [16] early established particle breakage constitutive model, but the parameterαwhich is obtained by curve fitting in the plastic flow rule just determined by empirical formula of particle breaking rate; Li Guoying and others [17] early established constitutive model considering particle breaking, regarding the rockfill as binary medium consist of a structural body and the breakage bands, the parameters a and b without definite physical meaning; Chi Shichun [18] found relationship of crushing energy dissipation and crushing parameter, and got the unified constitutive model considering soil shear dilatancy of particle breakage by introducing the particle breakage energy dissipation in energy balance equation of soil, the advantages of the model are able to describe the shear properties of coarse grained soil under different density and different stress level, but several parameters in the model has no definite physical meanings.
Constitutive model for rockfill material considering grain crushing[J].

Fig.3 Technology curve of nitriding catalyzed by rare earth Table 2 The penetration depth and surface hardness of the sample The sample number 1# 2# 3# 4# 5# Penetration depth/mm 0.53 0.52 0.54 0.56 0.52 Surface hardness HV 657 652 661 669 654 This process using the three sections of nitriding method: through ammonia started to pick up after 0.5 h emptying air inside the furnace, the temperature up to 500 ℃, the heat preservation 10 h, the purpose is to obtain high surface hardness, but this one phase deep shallow layer; Then heat up to 520 ℃, insulation 20 h, this stage gain deeper layer depth, but the surface hardness will be reduced; Cooling to 480 ℃, the heat preservation 10 h, to improve the surface hardness.
Under certain conditions, these defects will form "colloid gas" with rare earth elements as the core, and the air mass will eventually form nitride, which exists at the grain boundary and subgrain boundary, and has a binding and limiting effect on the grain, hindering the grain slip and forming a strong and toughening effect [6].

It can be seen from Figs. 4-5 that the further the distance away from the surface, the larger the grains.
Muhammad et al. [11] also found large scale and near surface deformations resulted in high dislocation density along with grain refinement phenomenon both under the wet cutting conditions, with an evidence of lower dislocation density for dry cutting.
Therefore, according to hardness variations with test load, the following conclusions can be drawn that more subsurface plastic deformations appear with higher dislocation density along with grain refinement under the wet milling conditions.
Acknowledgements The financial support of this study by Shenzhen Science and Technology Innovation Commission under the project numbers [Y01336107, GJHZ20180411143506667 and JCYJ20170817111811303] is gratefully acknowledged.

Refinement of particles and grain sizes occurs and the diffusion distances are reduced.
Moreover, SEM observations reveal that after 15h milling, particles are often found to be composed of a large number of grains (Fig.2.b), which form aggregates of a few micrometers [7].
It is well known that during high energy mechanical alloying of metallic powders, refinement of particles and grain size occur giving rise to a large fraction of micro-deformations.

These conditions are: 1) The forming temperature around half the absolute melting temperature. 2) Very low strain rate within the range from 10-2- 10-4/s. 3) The grain size will be less than 10µm; referred to it as micro-grain super plasticity. 4) The tensile elongation can reach more than 2000%.
These include crumple zones with a number of energy absorbing members at different parts in the vehicle, self- adjusting inertia-reel seat belts with pre-tensioners on all seats, head restrains, safety cages, airbags and energy absorbing interiors. [10] It is inadequate and impractical to rely solely on prototype testing for the global analysis of the collision, therefore an enormous amount of research works, both experimental and theoretical, were carried out [11-15].
This system is combining a grain refined super plastic zinc aluminum alloy in an equal channel angular pressing, ECAP, process.

Results of Experiments After reduction process metal nucleated in ilmenite grains and the oxide phase was enriched by the titanium oxides.
The metal nucleation occurred both on the surface and inside of the grains (Fig. 1, Table 1).
The composition of the phases, at. % Spectrum Mg Ti Mn Mo Fe O Metal after separation melting (Fig. 2, a) Spectrum 7 – – – 15.48 84.52 – Slag after separation melting (Fig. 2, b) Spectrum 8 – – – 1.82 98.18 – Spectrum 9 – – – 26.66 73.34 – Spectrum 10 1.22 27.01[ 0.48 – 7.78 63.51 Discussion At reduction temperature of 1300 ºС only iron can be reduced from ilmenite grain, whereas titanium remains in the oxide phase.
With temperature increase the number of thermal defects increases; as well as under reduction conditions the new defects and charged vacancies are also formed.

In this case, pressure causing plastic deformation of metal grains in friction significantly increases the level of defective grains.
Iron structure consists of ledeburite frame (Fig. 1a) and a large number of sulfide inclusions (Fig. 1b).
Central nuclei of cementite, stabilized by chrome form cementite grain structure of mottled iron (Fig. 2a).

According to the various parts of the steel wire tyre number to cut into several different sections.
Fine grain crusher cutter for rotary knife and the fixed knife.
Fine grain crusher fixed blade and rotating blade clearance value.
Fine grain crusher rotary blade mounted on the rotating roller cutter groove.

To obtain the necessary data, a large number of costly and time consuming experiments based on trial and error approaches must be carried out.
The thermal solution includes beam heating of the powder bed, conduction through and between the powder grains, and heat losses by vaporisation, radiation and convection.
They are, however, unable to predict fundamental geometric properties of the microstructure such as grain orientation, shape and impingement.
The grain growth rate does not depend on the extent of the transformation and is assumed to occur at the same rate in all directions.
It will allow us to simulate phenomena such as crystallisation, anisotropic grain growth, impingement and grain boundary formation.