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Here we consider ZCuSn3Zn8Pb6Ni1FeCo alloy.It is noted that high undercooling is the motive power of nanoparticles during solidification , which would act as heterogeneous nuclei to achieve outstanding contribution for grain refinement compared to ZCuSn3Zn8Pb6Ni1 alloy.
Tab. 2 Tensile data Material Tensile strength Yield strength Elongation /MPa /MPa /% ZCuSn3Zn8Pb1NiFeCo 430 235 21.0 ZCuSn3Zn8Pb6Ni 205 132 25.9 Fig. 1 True stress-true strain curves for the solutioned ZCuSn3Zn8Pb6Ni1FeCo alloy and ZCuSn3Zn8Pb6Ni1 3.2 Microstructure The microstructure of the ZCuSn3Zn8Pb6Ni1 and ZCuSn3Zn8Pb6Ni1FeCo alloy are shown in the optical micrograph in Fig. 2.It can be seen that ZCuSn3Zn8Pb6Ni1 alloy unfolds dendrite structure whose distance between the primary dendrite arm and secondary dendrite arm is 3mm more,while ZCuSn3Zn8Pb6Ni1FeCo alloy shows typical equiaxed grain whose average diameter of grain is 20~60μm.The effects of grain refinement with additions of iron and cobalt are prominent.
It is seen that the growth rate is very large for the smaller the radius of the particles.With such a large growth rate, it is very difficult to obtain the number of the dispersed iron nanoparticles in copper matrix melt during solidification.
Conclusion (1 ) In-situ iron nanoparticles can be formed during copper alloy solidification because of high undercooling,which would act as heterogeneous nuclei to achieve outstanding contribution for grain refinement
(4) Solution and water quenching treatment make the nanoparticles number increase and some preproduced precipitates grow because of exsolution and diffusion.

The varying order of C/N was DY> HY> DH > CK; the order of biological yield was DH>HY>DY> CK; the order of grain yield was HY>DH>DY> CK and the economic coefficient of HY was the highest in both years.
The soil microorganism was live organism, one of the most active soil factors[7]，the soil microorganism flora composing was largely influenced by the vary of number impacting on soil respiration.
In 2005,the number changes of the soil bacteria, actinomycetes and fungi was as same as in 2006(Table1), the number of soil microorganism was higher than CK in 2005, as same as in 2006, the changes of number of bacterium, actinomycetes and fungi in 2005 was same as in 2006, performing HY>DY>DH>CK, the number of all the index(except fungi) under HY treatment in both 2005 and 2006 represented the marked significant difference(P<0.01)than other treatments, in 2006, there had the same variety in soil microbial population compared with 2005, performing HY>DY>DH>CK, there were the most number of bacterium in soil microorganism, up to 70.96%～81.20% of total number, the second was actinomycetes, up to 16.32%～26.12% of total number, the fungi was the least, up to 3.20%～4.96% of total number.
The effect of different using fertilizer patterns on Biomass yield, grain yield, the impact of economic coefficient.
So respiration of soil microbe can reflect better the soil`s respiration, (Tab1, Tab2),in 2005 and 2006, the treatment of the large number of microbe, its respiration is large too.

Fig. 2 Micro-region morphologies of microstructure-simulated samples and actual welding HAZ samples (a) Simulated coarse-grain region, (b) Simulated fine-grain region, (c) Simulated critical region, (d) Actual coarse-grain region, (e) Actual fine-grain region and (f) Actual critical region.
A large number of dislocations were produced inside the material at the instant loading status.
In the coarse-grain region, grains are quite thick and large, grain boundaries are very less, internal dislocation tangles are short, and activate energy required for dislocation movement is big, so the energy needed to move in internal dislocation is large.
(a) Coarse-grain region (b) Fine-grain region (c) Critical region (d) Base metal.
Fig. 3 Creep strain - time curves in micro-regions of P92 steel welding HAZ samples Meanwhile, in the fine-grain region and the critical region, the microstructure is relatively thinner and smaller, grain number is bigger, grain boundaries are much more, and also the locations for the dislocation movement are more.

The density of grain boundary dislocations (GBDs) was calculated as number of dislocations locating on a boundary per the boundary length measured along the foil surface.
It was shown that no remarkable grain growth was found in grip section.
Grains are essentially stable against static grain coarsening.
Under dynamic annealing at 175ºC, no substantial grain growth takes place.
The average grain size in tension direction slightly increases from ~0.8 μm to ~1.1 μm; shape of grains retains nearly equiaxed (AR~1.2).

Significant differences in the number of dendrites, the shape and length of the arms were observed.
They are used both superalloys with polycrystalline structure with equiaxed grains [2], directionally solidified with columnar grains and single crystal structure.
Material and methods For examination purposes there were used three types of casting superalloys: polycrystalline Rene 80, columnar grained directionally solidified Mar M200Hf and single crystal CMSX-4.
Samples were polished using fine grained neutral alumina suspension pH7 (OP-AN) and acidic alumina suspension pH3 (OP-AA) of Struers.
Ziaja, Modelling of grain microstructure of IN-713C castings, Solid State Phenomena. 197 (2013) 83-88

(b) 10um (a) 10um Fig. 1 SEM images of the Mg fusion zone: (a) SAlMg-2; (b) SAlMg-1 Obviously there are two significantly different regions, one coarse grain zone and one fine grain zone, in the weld center.
The fine grain is in magnesium side area.
Fig. 2b can be clearly seen that a large number of tiny bright spot or strip phase disperse precipitate in the grains and grain intersection.
Fig. 3a and Fig. 3b show that the magnesium-side weld area consists of equiaxed crystal whose grains are coarse and the grain boundary clear.
Fig. 3c and Fig. 3d show that in the area near the aluminum side weld, the grain has finer size is dark brown and has no grain boundary.

The higher temperature promoted both; the transformation of the α phase into b, thus, losing its capability for pinning b grain boundaries, and a faster mobility of the grain boundaries itself.
Although the amount of recrystallized area is larger at lower strain rate, the number of recrystallized grains seems to be larger at higher strain rates.
Recovery seems to occur continuously from the grain boundary to the centre of the grain in the slow deformed samples (Fig.5b)).
The following could be concluded: - Dynamic recovery occurs heterogeneously for all the samples - The grain size of the grain formed by cDRX is the same as of the subgrain in all the cases
- The cumulation of dislocations at grain boundaries produces local recovery and local cDRX

Table 1 Chemical component of tested steel [%] Number C Si Mn Als Ti Cu Ni Cr V N V/N V0 0.08 0.23 0.81 ＜0.005 0.019 0.31 0.26 0.49 / 0.006 0 V5 0.08 0.22 0.83 ＜0.005 0.012 0.30 0.26 0.47 0.05 0.011 4.55 V10 0.08 0.28 0.87 ＜0.005 0.016 0.30 0.26 0.48 0.10 0.014 7.14 V15 0.07 0.27 0.84 ＜0.005 0.010 0.30 0.26 0.48 0.15 0.021 7.14 Table 2 Mechanical property of tested steel Number Rm [MPa] Akv(0℃) [J] V0 525 123 V5 610 112 V10 615 131 V15 615 131 10mm weathering slab with different content of vanadium was tested by Gleeble thermal simulation to evaluation vanadium’s function to property and microstructure under different technological processes according to CGHAZ’s mechanical property and microstructure’s changes before and after heat input under CO2 protection wielding (MAG)10kJ/cm.
Table 3 The microstructure of each wielding joint field Number situation microstructure Grain size [grade] V0 parent metal Blocky and acicular ferrite +pearlite 9.0 V5 Blocky and acicular ferrite +pearlite 9.0 V10 Ferrite + pearlite 9.5 V15 ferrite + pearlite 10.0 1V0 CGHAZ bainite + ferrite + pearlite 6.0 1V5 bainite + ferrite + pearlite 6.0 1V10 bainite + ferrite + pearlite 6.0 1V15 bainite + ferrite + pearlite 6.0 V0 V5 1V0 1V5 V10 V15 1V10 1V15 Fig.4 Microstructure of tested parent steel Fig.5 Structure of thermal simulated CGHAZ From the above test, it reflects the grain size of base metal was refined along with the increase of vanadium, and when it reached 10 degree with 0.15% vanadium, the grain were equal axial multilateral ferrite + pearlite.
The thermal simulated CGHAZ was unanimously coarsening from 9.0~10.0 to 6.0. 1V15 steel with 0.15% enjoyed the same grain size with 1V0 tested steel.
At the same time, these elements could be separate out completely and keep the refining grains between 9.0～10.0.
The solution temperature of second phase grains of TiN was high, so could not been dissolve easily in the test and functioned as pinning and refining grains’ size element in CGHAZ.

(ii) The dislocation density is calculated as line-length per unit volume, rather than as number per unit area.
The famous inverse square root relationship between grain size and flow stress will be apparent whenever the geometrically necessary dislocation density exceeds the background density, that is, at small grain sizes and moderate strains.
There will be stress discontinuities across grain boundaries parallel to the tensile axis.
A crack running along the grain boundaries releases this stress, but only within a sandwich of material centred on the crack and of thickness approximately equal to the grain size.
(10) The grain boundaries appear to act as Griffith cracks.

These are discussed in more detail in the following sections. 2.1 Effect of microstructure When testing bulk polycrystalline materials it is conventional to use a test load so that a large number of grains are sampled (>100) by the plastic zone associated with the indentation.
For instance, Figure 1 compares the indentation creep and hardness data for aluminium in three different forms, a single crystal, a polycrystal with grain size 20µm and a very thick polycrystalline coating with a grain size of 0.5µm which can be treated as a bulk material.
The hardness and creep behaviour of the single crystal and 20µm grain size material is almost identical and it can easily be shown that the deforming volume is much smaller than a single grain using equation 2 - the radius of the plastic zone is about ten times the residual indentation depth.
However, the higher hardness and creep rate of the 0.5µm grain size material is related to the fact that the deforming volume is now bigger than a single grain and the effects of grain boundaries cannot be ignored.
A number of indents were made and their positions accurately determined by AFM on this sample.