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The average grain diameter (d) was 62 mm.
Statistical distribution of grain size (e).
It is also observed in this microstructure large number of coarse precipitates with different sizes, particularly inside the grains, that did not dissolve completely during reheating process.
However a noticeable grain refinement was promoted.
White lines shows low angle grain boundaries (2-15 deg).

The grains of welding seam are refined and welding joints has a higher quality.
The primary grain of welding joint is refined, the segregation and chemistry non-homogeneity of weldment are reduced.
The number of inductor coil turn is 350 turns.
At the same time, the number of particles in LEM-CO2 welding seam is more than that of the general CO2 welding seam.
The grain growth directions of LEM-CO2 welding are disorderly obviously, so the strength and toughness of LEM-CO2 welding seam can benefit from this microstructure.

The study shows that the grains have strong retention on the resin matrix as well as longer tool life. 1.
The greatly increased number of working crystals can extend the tool life almost one order of magnitude.
In this paper, the performance of ABCD wire saw are investigated to find the grains have strong retention on the resin matrix as well as longer tool life. 2.
Fig. 2 Smooth grain type Fig. 3 Fracture type Fig. 4 Burr scalene Fig. 5 Lengthy type.
The surface roughness is smoother if the diamond grain size is smaller.

Different numbers of rotations were used to obtain different shear strains.
Fig. 2a) the elongated grain shows strong contrast changes caused by variations of the orientation.
From dark-field images at higher magnifications it can be concluded that the dark bands are composed of a large number of fine dark contrast lines with a width of 1-2 nanometres.
Fig. 2) have been encountered in coarse-grained Ni3Al [7].
Figure 5 shows lattice fringes of a coarse grained area CG in Ni3Al.

According to Scherrer's equation, we get the average grain size as following, x=0 sample is 5.9nm, x=0.25 is 4.4nm.
Only the average grain size is decreasing as the increasing number of doped iron.
The decreasing of the average grain size indicates that the Fe3+ has already doped into the crystal lattice of TiO2.
When x=0-0.20, the photocatalytic property is much more effective with the increasing number of iron-doped.
Over this amount of iron-doped, we get the lower photocatalytic property as the increasing number of iron-doped.

The average grain size (d) was determined by the linear intercept method.
The grain size increases with increasing B2O3 content and sintering temperature.
From Fig. 1, one can see that the grain size of ZnO increases and the amount of Zn7Sb2O12 spinel on the grain boundaries gradually decreases with the increase of B2O3 content.
The grain size obviously increases with increasing B2O3 content, while the amount of Zn7Sb2O12 spinel on the grain boundaries gradually decreases.
B2O3 doping inhibits the growth of Zn7Sb2O12 spinel on the grain boundaries.

It can be seen that the microstructure consists of a uniform globular grains for continuous shearing, but there exhibit a duplex mixture of the coarse and very fine globular grain for the condition with the shear-rate changing.
It can be deduced that these much finer globular grain should result from the burst nucleation during the rapid change of the shear-rate.
Meantime, it can be seen that, besides these new nucleated fine globular grain, the size of primary coarse globular grain was also decrease through the rapid change of the shear-rate.
Fig.4 shows the results got by plotting M -1 versus α, the wave number of the interface perturbation, at speed ratios ε = {0,20,40,60}.
Notice that for ε= 60 the neutral curve lies entirely beneath the horizontal axis, indicating that the instability has been eliminated for all physically realizable morphological numbers.

However, Sn and P elements in the intergranular microstructure diffuse into the crystal grains and adjacent grain boundaries at the same time as the grains grow, and the diffusion inside the grains was lower than the intergranular diffusion.
Fig. 9 showed after abrasion, the samples with different annealing temperatures have grooves and pits on the surface, and a large number of grooves form furrows.
When the annealing time is 120 min, the number of furrows and pits was less, and the depth was shallower.
When the annealing time was extended to 150 min, the number of furrows increased and the depth became deeper, accompanied by pits.
In Fig. 12 (d), it could be seen that the wear surface became rough and uneven, the exfoliated debris and the number of pits increase.

In prior studies that examined grain refining [5, 6], two elements were found to be necessary for achieving a refined grain structure.
First, nucleating agents, sufficient in number and potency, must be distributed throughout the alloy.
Second, grain growth must be sufficiently slow such that numerous nucleation agents become active and nucleate a new grain.
While the spherical cap model is widely used throughout the analysis of nucleation processes, there are a number of features in the model and evaluation procedure that deserve closer inspection.
Recent works [5] on the Al-Ti-B master alloy grain refining system have used the free growth model to predict inoculant potency.

Discrete Element Method Simulation of Residual Stresses in Grinding of Granite With Single Diamond Grain Liang Kang1,a, Yong Ye2,b 1Department of Business Administration, Chongqing College of Electronic Engineering, Chongqing China 2Department of Mechanical Engineering, Chongqing College of Electronic Engineering, Chongqing China amarilyn8311@163.com, brichard12@163.com Keywords: Granite, Grinding, Residual stresses, Discrete element method, Simulation Abstract.
The discrete element model and the model of single diamond grain grinding process of granite were constructed through numerical simulation and calibration of mechanical properties.
The discrete element model of granite material and two-dimension grinding with single diamond grain were built in this paper.
Discrete element simulation of granite grinding with single diamond grain Build the grinding model by using the microscopic parameters obtained from above simulation tests (see Fig. 2a): the model size is 0.8mm×0.2mm, the minimum particle radius is 2.2 mm, the ratio between the maximum and the minimum radius is 1.5, the number of particles is 5656, the model composed of closepacked particles is set in a cell which are fromed by three fixed walls, and the frictions between walls are ignored.
Ten different random numbers are selected for each simulation to invoid random error, influence laws of different machining conditions on the distribution of residual stress vs. depth are shown in Fig. 3-5.