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., they tend to be enriched at grain boundaries and/or phase boundaries for their relative large atomic radius and thus improve the microstructure stability of the solder.
Besides shearing/inflow collision, Brownian motion can also cause an increase to the number of aggregates in the system.

The cemented carbide produced by ultra-fine cobalt powder can reduce the porosity and avoid the formation of cobalt pool, which can separate WC grains.
When the temperature rises to 700°C, the product contains a large number of ß-Co with the proportion of ɑ-Co and ß-Co of 1:1 approximately.

In the modern world, forging process is applied by sets of die and tooling which deliver the compressive force to form desire shape from simple billet [2] This compressive force used in forming the parts, allows the grain to be aligned with the die contours which made the part to have a superior strength compared to casting and machining process [3].
This Simulation software package also allows the forgers to test a number of “what if” scenarios and determines the optimum condition without having to test-run the die [4].

First, part of the blocked and tangled dislocations will be open and become movable dislocations because of the obtained energy, and then, increase the number of the movable dislocations in the material.
Dynamic recovery and recrystallization could inhibit the grain growth, enhance the atomic motion ability, improve the effect of cancel each other of unlike dislocation, and increase dislocations moving distance, all resulted in great change of sample mechanical properties such as decreased tensile strength, increased plasticity and even restored to the state before the deformation.

The tress distribution of the 3d H-beam is shown in figure 5 , we can see that the greatest stress is in the outside of the waist, and distribute in the small rectangle area outside the waist, the smallest stress mainly distribute in the whole webs , the minimum stress is 2.18 MPa and maximum stress is 24.5 MPa, distribution of the stress is relatively uniform, and the number is smaller, far less than its yield limit of 400 MPa, the analysis results are good.
According to Q235 steel CCT curves, A and B cooling speed is far less than the formation of martensite minimum speed, so in the water range, accelerating cooling speed can obtain smaller grains of ferrite, and strengthening pearlite, bainite.

In the sintered surface (flank face before laser machining) the WC crystals of different grain sizes, which form the surface, can be recognized.
At higher temperatures the W-C system forms a number of different solid phases [10, 11].

The most important characteristics are a controlled reproducible billet temperature, high productivity and reliability, a short heating time which leads to a low volume of scale, little surface decarburisation and coarse-grain growth, an immediate readiness for operation, immediate switch-off when the forging machine is out of operation, and others [2].
Input data for numerical simulation of induction heating process Inductor length [mm] 1200 Internal diameter of induction coil [mm] 180 Number of turns 30 Geometry of turn [mm] 30×20 Distance between turns [mm] 10 Length of the billet [mm] 800 Diameter of the billet [mm] 100 Frequency [Hz] 1000 Voltage [V] 500 Heating process time [sec] 400 Due to the adapted to optimization procedures interface; the model provides extended options for variation of the heating system parameters or the work piece geometry and material properties, and optimal meshing of the work piece and surrounding area and for evaluating the process optimization abilities.

And, as the inhibitor of the grain growth, the replacement of Zr by Hf decreases the coercivity in the nanocrystaline Hitperm-type alloys[1-5].
After low-temperature annealing ,the volum fraction have a small number increase.

Voids can be formed in the areas of the occurrence of micro-cracks and other defects of the material, on grain boundaries, and, primarily, in the vicinity of the second phase particles (inclusions and precipitates), located inside the structure of the base material (matrix).
A number of mechanisms of void nucleation in the area of the inclusion and the adjacent matrix are distinguished.

Quasicontinuum (QC) method is one of the most excellent multiscale simulation methods, and it has been used in research of basic phenomena of crystal deformation, including fracture of grain boundaries, nanoindentation, crack-tip deformation, dislocation interacting, and so on.
The mainly reason is in that bulk material is a collection of a large number of atoms, and in the form of crystals, but in the actual crystal there are often inevitable dislocations and other defects.