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These particles are also referred to as dispersoids and are believed to impose a Zener drag on the moving grain boundary and thus reduce the grain size of a recrystallized product.
The number density along any grain boundary, determined by random line intercept measurements, is with 38 particles/100 µm the same as for the grain interior.
Recent analysis in model systems of Al-Zr showed zirconium segregating to grain boundaries and thus reducing grain boundary mobility [5, 6].
Conf. on Recrystallization and Grain Growth, B.
Conf. on Recrystallization and Grain Growth, B.

Fine grain graphite has been an important material for tribologically loaded components such as seals and bearings for almost a century.
Therefore the strategy to improve the strength of fine grain graphite has always been to come to smaller grain sizes and so to smaller voids.
Unlike state-of-the-art fine grain graphite the carbon materials derived from sinterable carbon precursors consist of one single phase, free of grain boundaries.
Overextended milling led to self assembly and agglomeration of the particles thus increasing the grain sizes.
The friction coefficients were in a similar range as for high-end conventional fine-grain-graphite.

In the course of scientific and technological progress, an increasing number of materials have been created that met the necessary operational requirements.
The calculation of the linear density of twin boundaries was carried out by counting the number of intersections of the grid lines applied to the images and with twin borders.
Grains unfavorable for twinning are deformed by sliding.
The content of such grains was small.
Twining was observed in all grains and its morphology weakly depends on the grain orientation.

The specimens are numbered from sample 1 to sample 20.
After a fatigue crack initiates and begins to grow, every a certain cycles, the test is interrupted, the cycle numbers and short crack growth rates are recorded using the optical microscopy to take photos for specimen’s front edge at notch root.
For a polygon grain, drawing the grain’s circumscribed circle, and the circumscribed circle’s diameter is selected as the characteristic size of polygon grain, while for a rectangle grain, the length of rectangle’s diagonal is measured as the characteristic size of rectangle grain.
Using a statistical average method, the characteristic sizes of polygon grains and that of rectangle grains are individually measured, and the mean value of the characteristic sizes of polygon grains and that of rectangle grains are calculated as 0.15mm and 0.17 mm.
The mean size of polygon grains is approximately equal to that of rectangle grains, and the average value of polygon grain’s and rectangle grain’s characteristic size is calculated as 0.16mm, which is determined as the grain size of GH4133B superalloy.

Unfortunately, we could not find the rutile grain nucleated in the anatase particle due to very fast grain growth.
The numbers above indicates the particle size of anatase phase in diameter.
Unfortunately, however, we could not find the rutile grain nucleated in the anatase particle.
If the rutile grain is imbedded and trapped in the anatase particle after the phase transformation, the grain size of anatase should become smaller and smaller with the formation of rutile phase.
Unfortunately, however, we could not find the rutile grain nucleated or imbedded in anatase particle due to a very fast grain growth.

Because Bi is brittle phase and distributed in the copper alloy matrix grain boundaries as thin ribbon network.
With the increasing of the content of Bi, a large number of Bi gathers in copper grain boundaries and begins to join together to form a status like a continuous chip mesh belt, as what shown in the metallographic diagrams 5# and 7# of copper-bismuth bearing material in Figure 1.
Due to without brittle Bi phase, the number of crack source in the organization of material is few, and the copper alloy matrix which has good toughness in the process of impact fracture has strong shears deformation, microvoids form in the local region, begin to grow and gather.
The SEM photographs of fracture show that there is cracks which grow to depth along the grain boundaries.
The strong Bi energy peak occurs at the fracture grain boundaries, which proves that the crack generation,growth,until fracture occur along the grain boundaries of Bi-rich phase.

Controlling the grain size is also very difficult in the case of forgings.
In the present study, forged IN 718 alloy having 300 mm grain size is tested at room temperature (RT).
The material shows equiaxed grains with grain size varying from 150 mm to 290 mm.
The loop shape also significantly varied as the number of cycles increased.
Number of reversals.

The heat is inversely proportional with the alloy grain sizes.
Introduction For thousands of years the development of practical alloy systems has been based mainly on one principal element as the matrix, as in iron-based, copper-based, and aluminum-based alloys, limiting the number of applicable alloy systems, even though a substantial amount of other elements is incorporated for property/processing enhancement [1,2].
The fusion zone grain size is less than elsewhere, from the Fig.
Fig.5 Sample 5 after Welding Dendritic grain size is shown in Fig.6. a and b are the grain size of horizontal and vertical, respectively.
Four samples grain size were measured and draw the diagram of grain size versus heat, as shown in Fig.7(a) and Fig7(b).

As it is shown in Fig. 1 grain B is too big and grain A is too small.
Only some of abrasives are active, which means they roll like grain C or slide like grain D.
First of all strongest loaded grains disintegrate.
As a consequence, the structure of the lapping tool is changed, as follows: the number of bigger grains diminish, while the number of smaller grains is growing.
Due to the changing track and velocity of abrasives, some grains crash with each other or with grain fragments.

Natural nanostructure in polycrystalline silicon was utilised for charging islands and its grain boundaries were modified by a multi-step annealing technique to form grain-boundary tunnelling barriers.
Subsequent annealing increases the grain-boundary tunnelling barrier height and resistance.
Introduction A single-electron transistor (SET) is a novel device where the on-off states can be formed by a single-electron, without any statistical fluctuation in electron number[1,2,3].
( ) �� � � �� � �−�� � � �� � �−�� � � �� � � = Tnk qV Tk qV m Tk qnVI B B B B P 2 sinh exp 2 2 2/1 * π (1) , where q denotes a carrier charge, m* an effective mass, kB the Boltzmann constant, VB a barrier height, T temperature, n number of grain boundaries, and V an applied voltage.
We found that the charging island is made of crystalline grains covered by an oxide GB barrier[4]