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Thermohydrogen processing of Ti-6Al-4V, the most popular �+� alloy which accounts for more than half the total titanium sales, has been studied in a number of investigations [10-18], with the emphasis on improved workability and refinement of the microstructure [1, 10-12, 19, 20].
Ti-6Al-4V – H PHASE DIAGRAM As cast and hot isostatically pressed (HIP’d) Ti-6Al-4V plate supplied by Precision Castparts Corporation (PCC), Portland, Oregon, had a coarse structure, with an average prior beta grain size of 0.97mm and an average lamellar spacing of 5µm (Figure 1).
After hydrogenation, the prior beta grain size, as anticipated, remained unchanged. 2 20µm (a) (a) (b) Figure 1

This is because Indium existed into the grain boundary of the matrix so as to this form of the solid solution with the gap.
A large number of iron atoms were sputtered out from the surface.
This was due to solid solution strengthening, grain refinement and Copper and Indium lubrication all had common effects for the surface of the infiltrated Stainless Steel.

Different soil properties, and soil have different degree and strong corrosion to the pipe, and the leakage point also is not easy to be found in time, as well as the underground pipeline maintenance needs a large number of earthwork, more hard than the construction of new line.
Microcrystalline fineness with low grade, expanding crack extending the grain, prone to cracking, if tracing nickel, copper, chromium can improve the corrosion resistance.

The rate of heat and mass transfer at different conditions in the cavity is measured in terms of the average Nusselt number and the average Sherwood number.
In general, the average Nusselt and Sherwood numbers have the same behavior.
A number of relevant results have been presented in this paper for different values of buoyancy ratio (−5≤N≤5), while inclination angle, Rayleigh, Lewis and Prandlt numbers are taken as -45°, 2*107, 3 and 4.5 respectively.
The porosity and the Darcy number of the 2 layers are ε1=0.6, ε2=0.4, Da1=10-5 and Da2=10-4.
In general, the average Nusselt and Sherwood numbers increase when |a| increases.

Determining the anisotropy coefficients of an ultra fine grained Al6082 alloy subjected to ECAP Gyorgy Krallics1, a , Arpad Fodor2,b 1,2 Department of Material Science and Engineering Budapest University of Technology and Economics, 1111 Budapest, Bertalan L. u. 7.
material after 1 pass versus reduction of the equivalent strain 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 -9x10 -11 -6x10 -11 -3x10 -11 0 3x10 -11 6x10 -11 9x10 -11 1x10 -10 Xi coefficients [MPa 1/4 ] Equivalent strain X1 X2 X3 X4 X5 Fig. 2 Xi anisotropic coefficients of the material after 4 pass versus reduction of the height 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 -1x10 -10 -8x10 -11 -4x10 -11 0 4x10 -11 8x10 -11 1x10 -10 2x10 -10 Xi coefficients [MPa 1/4 ] Equivalent strain X1 X2 X3 X4 X5 Fig. 3 Xi anisotropic coefficients of the material after 8 pass versus reduction of the height In order to characterize the ECAP process, the initial values of the anisotropy parameters at given pass were put into one diagram (Fig. 4) which shows the changing history of the anisotropic parameters. 012345678 -1x10-9 -8x10-10 -4x10-10 0 4x10 -10 8x10 -10 1x10 -9 Xi coefficients [MPa1/4 ] Number
of passes X1 X2 X3 X4 X5 Fig. 4 Xi initial anisotropic coefficients versus number of passes After determining the anisotropy coefficients during the whole upsetting the calculation of the equivalent stress becomes possible using the next expression: ()()()()() () 43 22 1 11 33 2 11 33 22 33 3 11 33 22 33 4 1 5234 3 22 XX X XXXXX σσ σσσσ σσ σσ σ −+ − −+ − − =+ ++++ ()()() ( ) 3 411332233 52233 1 5234 3 22 XX XXXXX σσσσ σσ −−+− + ++++ (18) Rate of the plastic work [7] was used to calculate the equivalent plastic strain rate: p ij ijw =σε&& (19) where p w& is the rate of plastic work, ijσ is the yield stress, ijε& is the strain-rate under uniaxial tension.

Accordingly, the main scope of this paper is to highlight the enhancement of a number of properties of magnesium through the use of nano-length scale, amorphous and hollow reinforcements.
DMD is similar to spray processing but involves lower impinging gas pressure to disintegrate the melt as it enters the mold producing bulk material with finer grain size and better mechanical properties.
The improvement in ductility observed for ceramic reinforcements may be due to reduction in grain size, the activation of non-basal slip systems and texture modification for uniformly distributed nano reinforcements.

By means of further investigations on the process interfaces, it will be possible to optimize the interaction of the whole LPBF process chain to increase the number of qualified materials with better performance properties.
This leads to high cooling rates by self-quenching and thus fine grain structures.
Some microsections of the as printed cubic samples are etched with V2A etchant to have a look at the grain structure.

Yuan also conducted similar tensile tests with variations in grain size and temperature [15].
In the grain size variations, a maximum stress range of 8 GPa to 10 GPa was obtained.
Other research focused more specifically on the {100} and [110] deformation directions with variations in grain size [17, 18].
The chosen number of atoms was based on consideration of the number of carbon atoms to be added later in carbon steel cell.
Additionally, such materials must have polycrystalline structures with numerous grain boundaries.

Main parameters of lapping and polishing (e.g. abrasive disk rotate speed, abrasive disk stress, abrasive category, abrasive grain diameter, slurry density and abrasive disk material) were changed to find out impact parameters of surface quality.
Moreover, there are a number of impurities and wax on the floatation cushion surface after polishing processing.

The microstructure of the degraded 1Cr0.5Mo steel specimen, Fig.1 (a), contains a greater number of fine carbide particles within the ferrite grains than the reheat-treated specimen, Fig.1 (b).
Fig.6 shows the relationship between the number of cycles and the friction force obtained in the fretting fatigue tests.
Fig.7 also shows the relationship between the number of cycles and the relative slip amplitude that was measured at the edge of the pads.
It would seem that this difference is associated with the number and morphology of carbide particle in materials.
The carbide particles in the degraded material are not only larger in number but also coarser compared to those in the reheat-treated materials.