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Fig.1 Cross-section morphology of Ni(P)-Sn coating on AZ91D (a) before diffusion; (b) after diffusion; Table 1 EDS analysis results of Ni(P)-Sn interface in Fig. 1 Composition /at% Marked numbers ① ② ③ ④ ⑤ ⑥ P 3.75 6.24 31.93 22.69 1.54 0.92 Ni 39.44 93.76 68.07 43.08 42.42 2.26 Sn 52.88 0 0 34.23 56.66 96.19 Table.1 shows that Sn is not found at point 2 and 3, but the percentage of Sn at point 4 is 34.24%, which indicates that there is almost no Sn spreads into the Ni layer.
Fig.2(b) shows the surface is smooth, the grain grows along the surface, and cracks have been observed on the surface of compounds, while the fig.2(c) shows the compounds whose growth pattern is longitudinal, break through the Sn coating, and cause significant damage on the junction of the Sn coating.
The difference of compounds growth type may be due to temperature and internal stress that lead the growth direction of grain different.

Introduction To convert low-grade ores to saleable concentrates,especially with curreent low price and high production costs,requires a high level of technology and control,and a careful balance between concerntrate grades ,recovery and milling cost .Substantial increases in copper prices since 2003 have resulted in the reopening of many mines and significant increases in copper flotation capacity.The development of froth flotation had an enormous impact on copper mining ,enabling the most abundant primary mineral ,chalcopyrite ,and other sulphides to be efficiently separated from ores of relatively low grade and fine grain size.
Alkaline circuits of pH 8.5-12 are generally used,with lime controlling the pH and depressing any pyrite present.Through a large number of exploration test , the direct flotation separation processes was selected.
The main minerals are copper sulphide minerals and oxide copper.The main gangue minerals were quartz and carbonate minerals.Pyrite and copper minerals mainly fine-grained disseminated.

The basic consideration when applying niobium to steels, is that it forms very stable carbides to facilitate grain refinement and precipitation hardening as strengthening mechanisms in structural steels.
The addition of niobium carbide to tools steels prevents the grain growth at these high temperatures of hardening procedures of heat treatment [1].
The demand for low-cost high-performance tool steels has resulted in a number of attempts to replace some of the expensive alloying elements (W, Mo) with niobium [3,4].

However, a number of undesirable properties including poor corrosion and wear resistance, and high chemica1 reactivity, limit their extensive use in many applications.
The reasons of increasing microhardness of alloying layer are fine grain, Al content increases and a mass of Mg17Al12, Mg2Al3 phase distribution in melting layer.
The reason is the grain size in melting layer was obviously refined, and the occurrence of network intensive second phase, so that the corrosion rate is decreased.

These membranes offer a number of excellent physical properties for devices applications [5-7], and most of them can be quite conductive (in contrast to SiNx).
Despite the noticeable grains and roughness, as shown in Fig. 2a, b & c, arrays of circular holes with nominal diameters of 1μm, 0.5μm, 200nm, and 100nm are fabricated by a FIB current of ~0.1nA.
Many small through holes are realized with measured diameters down to ~95nm (smaller than size of the grains on this membrane).

Moreover, diffusion properties in this system are well known (within bulk, along grain boundaries, or dislocations) [ 7,8].
We explained this effect by the increase, due to work hardening, of the number of dislocations, which supports plastic deformation according to Maugis [14].
Moreover there is dynamic recrystallization of metal during the elaboration of the junction, which leads to the presence of fine grains accelerating the speed of creep of the metal joint.

For a ring die, whether the RHD is smaller or bigger, the quality of pellet is not good, the smaller the RHD, the easier the extrusion, then the grain character is relax; whereas .the bigger the RHD, the more difficult the extrusion, then the grain character is hard.
Fig.4（a） Original structure Fig.4（b） Equivalent structure Suppose the original structure and equivalent structure occurs same longitudinal strain, namely z1= z2, and then the equivalent elastic modulus E2 can be described as (9) Where r is the mold hole diameter; n is the number of mold holes.

With increase in magnetic flux density, strength and area of contact of the magnetic abrasive brush increases, resulting in greater number of indentations into the workpiece.
When circumferential speed increases, the centrifugal force acting on the abrasive grains also increases which may result in ejection of grains from the working space, thereby decreasing the PISF.

Since there are no grain boundaries, the nickel-base single crystal superalloys eliminate the void-damages localized at grain boundaries.
Large crack in the top left you can see there are small cracks, as shown in Fig 3 (c) shown in the creep late alloy can be formed at various crack initiation, subsequent crack propagation, a number of micro-crack growth accelerated alloy Creep fracture process, in which crack propagation direction perpendicular to the applied stress axis, the crack tip smaller, and crack open a larger size, the crack tearing along the axis of applied stress due to expansion of broadening.

The medical community has accepted bioceramics materials after a number of clinical tests through a several in-vitro and in-vivo evaluations [1][2].
It has been claimed that the microstructure of ceramics is highly dependent on the applied manufacturing process (sintering temperature, purity of the powder, size and distribution of the grains, density and porosity) and subsequently effect on both the mechanical and biological properties [5].
When the composites being accompanied with YSZ, as transformation toughening agent acted to Al2O3 grains, which was possibly enhanced the physical and mechanical properties.