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In this paper, a concept is described of how a laser based manufacturing centre, comprised of a number of individual process cells, together with integrated pre and post SPF/DB operations, would work and the benefits that would result.
Furthermore, the metallurgical conditions required for a material to behave superplastically, such as fine grain size, with titanium alloys, are often corrupted during the process.
Each of the four cells require separation for a number of reasons.
Fig 5 Chart showing grain-growth as a function of temperature, and the reduction in flow-stress that occurs accordingly Strain rate sensitivity against time 0.4 0.5 0.6 0.7 0.8 0.9 1 0 2 4 6 8 10 12 14 Time (h) Sensitivity index m 5 10 15 20 Grain size (microns) m gLasers and ceramics Research at UWE’s Aerospace Manufacturing Research Centre (AMRC) has focused on using laser(s) to perform virtually all of the operations required to produce an SPF/DB component, from cutting the initial blank from sheet material to final trimming and hole drilling after forming.

Assume: R: particle diameter; y(r): the total number of particles smaller than r / the total number of particles; D: fractal dimension; B: distribution index P: The particle density of diameter r; kv: Volume shape factor; m(r): the cumulative mass of particle diameter less than r; m: total mass; there: when: m(r)/m∝ rb (1) dm(r)= rb-1dr (2) because of: y(r)∝-r-D (3) dy(r)∝r-D-1dr (4) dm(r)=pkvr3 dy(r)∝r3r-D-1d
Granulated steel slag has small grain size with specific surface areas and indensity of heat exchange increasing.
The GQSS was spherical, Its average grain size less than 2mm accounted for almost 97%, which basically was not to use broken and to be directly grind.
The grain composition and specific surface areas of steel slag were tested with a grinding time 30min,50min,70min and 90min respectively, according to the Eq. 7~ Eq. 14 calculated the fractal dimension D and correlation coefficient value R.

In [18] a number of techniques for mixing the particles into the melt have been reported, such as particle injection with inert gas or using pre-infiltrated powder-matrix pellets.
Grain sizes were measured according to ISO13320 with a Malvern Mastersizer 2000 and densities with a Porotec helium pycnometer.
Table 1: Density and grain size of experimental particle material AlB2 a) B b) B4C c) Theoretical density [kg m-3] 3.19 [20] 2.35 [8] 2.52 [21] Pycnometer density [kg m-3] 2.67 2.20 2.53 Grain size d50 [µm] 4.64 2.98 6.77 a) Zhengzhou Dongyao Nano Materials Co., Ltd., Zhengzhou, China b) H.C.
Acknoledgement The authors would like to thank the Cluster of Excellence “Engineering of Advanced Materials” (EAM), funded by the German Research Foundation (DFG) under grant number EXC 315/2, and the Graduate Schools “Advanced Materials and Processes”(GSAMP) for financial support.

Using Scherer formula, the average grain size of the coating with 7.76 wt.% phosphorus content was calculated to be about 1.4 nm.
In addition, the full width at half maximum of diffraction peaks is larger at the higher phosphorus content, indicating that the Ni–P coating with higher phosphorus content in this study exhibits amorphous structure with smaller grain size of nano meter.
These results might be ascribed to the increasing of the numbers of phosphorus atoms within the f.c.c.
In other words, the nodule size of the Ni–P coatings increases but the nodule number decreases with increasing pH value (i.e., decreasing phosphorus content of the coating).
Fig. 5e shows that there is little abrasive wear with few fine grains pull-out along the sliding direction.

Hardness of the coating was chosen as a key property, since it is indicative of the work-hardened state of the material in the layer, the grain size and hence the coating strength.
Two materials were used for substrate, an A1 aluminum alloy (UNS number A91100), and a low carbon steel (UNS number G10100).
As a consequence, the coating is composed of titanium grains which have undergone a much more severe plastic deformation, and become work-hardened to a greater extent.
This is likely to be reflected in the grain size and dislocation density in the two coatings.

Special interest is the use for this purpose of boron nitride, which is due to the similarity of a number of properties, the electronic analogue of carbon [23].
Prolonged frictional loading leads to a progressive loosening of the metal's surface layer, associated with an increase in the number of foci of destruction [26].
Grinding of the block microstructure leads to an increase the limit of macroscopic elasticity and resistance to fatigue failure by reducing grain-boundary cracking [28].
Allocation of particles, apparently, carbides and δ-ferrite, is observed along the grain boundaries.
The deposited metal of the coating with borides has a complex composition structure with a martensitic matrix, a large number of eutectics, and particles of reinforcing phases.

Inclusions of phosphides: a) acting as nuclei for graphite (nodule 2.1-8); b) in the grain boundary without any graphite associated (sample 6.3) Figure 7.
In irons with low percentage of Ti, no Ti(CN) were detected and the number of complex (MgSiAl)N was significant.
As the percentage of Ti increases, the number of Ti carbonitrides is enhanced, and the number of complex nitrides decreases, up to a maximum of 0.036% Ti in the iron, where no (MgSiAl)N were found as nuclei.
Both complex nitrides and carbonitrides seemed to restrict the growth of the sulfides increasing the number of nodules.
Ce formed silicates or sulfides, but not in significant numbers.

MR: Mean Rank, N: Number of samples, RS: Rank Sum.
The SEM images of Fig. 1 suggest that the microstructure of the produced samples sintered at 1300oC is very dense and the grains are well formed.
Moreover, the grain boundaries suggest equilibrium regime because the dihedral angles formed are 120o.
The X-ray diffraction analysis showed that the produced samples sintered at 1000oC (Fig. 2) consist mainly of HA (ASTM card number 01-089-6438) and some secondary phases of calcium phosphate hydrate phases (ASTM card number 00-050-0582).
When the sintering temperatures increases to 1300°C, the X-ray diffraction analysis (Fig. 3) showed that the produced samples consist of HA (ASTM card number 01-084-1998), some secondary phases of whitlockite (TCP, ASTM card number 00-055-0898) and calcium phosphate oxide (ASTM card number 01-070-1379).

Introduction A large number of modern electronic device applications are based on hierarchical micrometer- and nanometer-sized building blocks.
Hence, B represents a mean grain size.
This defines the location of the vertices of a number of triangles.
Only by this way one can reduce finite pixel number effects and to minimize the arising from finite pixel numbers spectral leakage [16].
According to eq. (1), the PSD runs (with some fluctuations) parallel to the k axis at small wave-numbers.

A large number of studies have been conducted to evaluate the impact of alternating strain on the fatigue life of Ti-Ni superelastic alloys [2-5], but only a few focused on the impact of the mean strain [6-10].
The evolution of the dissipated energy as a function of the number of superelastic cycles is plotted in Figure 4 for different levels of mean and alternating strains.
max min min max loading unloading Dissipated Energy (1) 0 1 2 3 4 5 6 7102 103 104 105 Number of cycles, Nf Dissipated energy at 200 th cycle, MJ/m3 ea = 0.3 ea < 0.075 ea = 0.10 ea = 0.15 ea = 0.225 = 0.2ea em = 0.5 Mean strain Arrow - increase in mean strain 0 200 400 600 800 1000 1200 1400 0 0.02 0.04 0.06 0.08 0.1 0.12 Strain, e Stress, MPA 1st cycle 200th cycle Hysteretic Area em=0.3; eA =0.15 Figure 4: Relationship between dissipated energy measured at the 200th cycle, alternating strain ( a), mean strain ( m) and the number of cycles to failure.
However, contrary to a certain number of previous studies [6-10], it was found that, notwithstanding alternating strain amplitude, no fatigue life improvement associated with an increase in mean strain is observed in the framework of this study.
In respect to the internal factors, note that the diameter of the filaments tested in this study (100µm) is close to the alloy grain size (10-20µm), which could change the fatigue crack propagation mechanisms.