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A number of cutting experiments with single abrasive grit were performed to study the mechanism of grit-workpiece interaction [1].
Simulative model of single grit cutting Geometric Model of Single Grit In authors’ previous research, white light interferometer was employed to measure the surface topography of alumina grinding wheels with different grain size [8].
Rong, Research on microscopic grain-workpiece interaction in grinding through micro-cutting simulation, part 2: factorial study, Adv.

When increasing the charge to 2C, the Sn grains increase and begin to show a tetragonal crystal shape while the pore size reduced a little (Fig. 2b).
The Sn grains also grow over 200 nm with a clear tetragonal structure.
With the increase of cycle number, the charge and discharge plateaus are becoming less obvious, which indicate the capacity loss with cycles.

The samples used for experimental DTA in microwaves have been a homogeneous mixture of Fe2O3+BaCO3 with the follows characteristics: Table 1 The characteristics of the sample heated in microwaves field Sample Characteristics Code Sample Milling Time [ h ] Grain size [ nm ] Pressing Force [ MPa ] Sample Size Height/Diameter [ mm ] HM 0 1120 300 4/12 HM5 5 400 300 4/12 HM20 20 100 300 4/12 The inert material used in experiments was barium ferrite type M sintered in conventional furnace with electrical resistance.
An important observation is the temperature evolution in the inert material without milling time, because this behaviour shows us that will not be necessary to use a planetary ball to mill the homogeneous mixture to reduce his grains size to obtain a easy heating in microwave field.
Acknowledgement This work was partially supported by the grant number 47c/2014, awarded in the internal grant competition of the University of Craiova References [1] I.

Since the surface free energy is considered to be a driving force in the sintering process, a number of sintering models have been researched for the initial stage of sintering and the resulting equations can be summarized as follows[15]
(4) Where K1 and w are constant, D is the diffusivity, γs is the surface energy, Ω is the atomic volume, G is the particle or grain size, k is the Boltzmann's constant, T is temperature, t is sintering time and m is a constant depending on the diffusion path.
Kang (2005) Sintering: Densification, Grain Growth & Microstructure, Elsevier Butterworth- Heinemann, Burlington.

Recently, much importance was attached to synthesis and characterization of nanocrystalline iron nitrides for their unique magnetic properties and improved performances determined by the smaller grain/particle size, surface structure and inter-particle interaction[10-15].
A careful calculation, based on the (200) diffraction peak of its XRD pattern, gives its lattice parameter = 2.870 Å, corresponding to the standard value a = 2.876 Å of Fe-Cr (Card number: 34-0396).
Besides, from the half-width of XRD peaks of the powder samples (shown in a of Fig. 1(b)), the grain size is estimated as 50–80 nm for nano-crystalline (Cr,Fe)N.

It can be due to that specific surface area of pore forming agent with the small particle size is large and the particle number is more than those with large particle size.
When it mixed with alumina powder, it can be used as fine grain skeleton to fill in pores and increase the grain bulk density due to relatively high homogeneous mixing degree.

The numbers indicate the minimum yield strength in ksi.
Fig. 7 illustrates the weld root at higher magnification where it appears grain growth has occurred across this lazy-S feature.
Micrograph illustrating grain growth across the root flaw.

All methods are based on assessment of a high number of penetration tests at locations affected by seismic activity, where in some, liquefaction of soils in the ground has been observed while in others, liquefaction has not occurred.
Fig. 2 Examples of CRR curves used in the respective methods Fig. 2a [3], Fig. 2b [4] Correction of measured penetration resistance qc is based on consideration of the magnitude of effective geostatic stress or consideration of the content of fine-grain particles in the soil.
The granularity of brown-coal ashes corresponds to fine-grain sand to silty sand.

Grains are located in the direction of heat removal.
The grain size is 100-500 μm.
The surface of the rupture site is characterized by a large number of facets, which characterizes material as a sufficiently high plasticity, and characteristic of brittle fracture by metallic luster.

The microstructure of as-cast EN AC-46500 (Fig. 6) consists of primary grains of the α-solid.
In contrast to the thixocasting process, eutectic microconstituent occluded in the α-grains was not observed.
Acknowledgements The authors thank the Comisión Interministerial de Ciencia y tecnología (CICYT) of Spain for the support provided under projects numbers: DPI2005-02456 and CICYT DPI2007-62948.