Search results

The results show that the grains of the matrix are refined; the connection is fine; the connection mechanism is diffusional bond; The wear surface had relatively shallow gully; Typical TEM morphologies of super-high manganese steel was high density dislocation, deformation bands, twin.
Under the new and old process, the grains of high manganese steel are coarse in Fig.1.
Under the old process, there are a large number of carbides shown in Fig.1b.
Fig.8 TEM micrographs showing deformation twinning in Hadfield steel Conclusions In super-high manganese steel, the carbides precipitation along the grain are less, carbides are dispersed.

(4) where Γ is the Gibbs-Thomson coefficient, R is the dendrite tip radius, Pei is the Peclet number for i, mi is the liquidus slope, C0,i is the initial concentration for i, ki is the partition coefficient for i, ζc(Pei) is a function of the Peclet number, Iv(Pei) is the Ivantsov solution (i=Cr or Al) and Ghkl is the average thermal gradient near the tip
Epitaxial [010] and [100] dendrite impinge each other to form centerline grain boundary.
The weld defects of centerline grain boundary formation, asymmetrical stray grain formation and solidification cracking are thus mitigated by decreasing size of aluminum-rich dendrite growth region.
Grain structure development in directional solidification of nickel-based superalloys.
Analysis of stray grain formation in single-crystal nickel-based superalloy welds.

For example, appropriate Sc and Zr additions have a significant impact on the grain structure of 2xxx alloys and thus on performance.
Data correspond to industrially processed 35 mm plate. 2.2 New dispersoid combinations for 2xxx alloys The use of combined Sc and Zr additions to 5xxx and 7xxx alloys to maintain an unrecrystallized grain structure is now well known and exploited in a number of alloy developments.
Nevertheless, even the levels of Sc that can be added without generating significant volume fractions of (detrimental) coarse phases during ingot casting have a marked effect on grain structure.
The 2x24Zr plate is largely recrystallized with coarser grains, whereas the further addition of 0.03%Sc results in a completely unrecrystallized microstructure with fine elongated grains.
Secondly, there is still potential in the improvement of grain structure, via both grain refining processes and grain structure control.

A number of reasons have been offered in the literature to explain this observation, the principal one being crack closure [2-8].
For example, microstructural effects can have a significant effect on short crack growth rates; e.g. where some grains have slip systems favourably orientated to the loading direction.
Note that this will not necessarily be the easiest path through a particular grain but the easiest path for the entire crack front through the material.
For short cracks (DK < 2 MPa√m) the average da/dN or crack growth per cycle (for high R CA cycles) is observed to vary inversely with the number of cycles in the CA sequence, that is, the crack growth rate per cycle slowed down with the number of subsequent CA load cycles applied.
There will be an upper limit to this inefficiency that is possibly dependent on the Kmax as well as material issues; grain size, available slip systems, other barriers to growth etc.

It was discovered that the reaction of the alkaline proportions of red mud with the agent is greatest with fine granularity but for red mud, it does not change depending upon the size of the grain.
After drying the sample for determining elution characteristics, the samples were sieved and a fraction with a grain size of 1.875 mm (1.25mm - 2.50mm fraction) was separated and used in columns and rinsed with a sulphuric acid of various concentrations.
When rinsing red mud (Fig. 5, 6), varying concentrations of H2SO4 was expressed in the number and dependence of released Fe3+ ions.
Only brown mud met the assumed best leaching of alkaline compounds in mud with the greatest number of particles, i.e. the lowest granularity.
During the experiments, we also observed a varying colour intensity of eluates from brown (when the dust proportion was eluted from the grains of mud) to colourless eluates to yellow, which indicated an increased amount of iron.

For hydrogen, obstacles can be created by: - lattice defects, - precipitates, - phase boundaries, - grain boundaries, grain boundary intersections, - cavities, - cracks, microcracks, other material continuity defects.
Therefore, efforts should be made to minimize the number of obstacles for hydrogen atoms.
It can be seen that the coarse-grained HAZ (CGHAZ) is the most brittle, which means that this is the critical part.
The effect of the number of passes was investigated in an experiment [31] and the results are shown in Fig. 13.
- Minimize the number of imperfections in the weld and strict weld quality requirements are needed.

When the LSMO compound doped by Ni, the number of ferromagnetic bonding decreases and antiferromagnetic bonding increases.
It could be happened due to the alignment of Mn spins inside the grains or at the grain boundaries.
In the doped sample, Ni-doping enhanced magnetic disorder inside the grain and at the grain boundaries causing electron scattering and resulting in relatively high resistivity [13].
Higher field raised up the number of spin alignment and increased the MR value.
Sun, Grain-boundary effects on the magnetoresistance properties of perovskite manganite films, Phys.

What’s more, the X80 steel was more vulnerable to HE, and that owns to the minor grain size and M-A microstructure, which may trap more hydrogen atoms, and thus led to the HE susceptibility difference between the two steels.
Hydrogen embrittlement of steel was first reported by Johnson [2] and since then, a great number of studies had been focused on the HE of steels, including various types of steels and other alloys, in the literature.
Nevertheless, Thorsten Michler et al. [8] studied different kinds of body-centered cubic steels, they gave the priority to the hydrogen enhanced localized plasticity for the HE of steel, rather than strength or final grain size.
Besides, the X80 steel has smaller grain dimension than that for X65 steel.
As for X80 steel, it has minor grain size, and that means more grain boundaries, which could offer more hydrogen trap sites, besides, M-A would trap a great number of hydrogen atoms as well, so there would be a susceptibility difference between the two steels to HE.

A number of recommendations are given for the effective use of gangue and fly ash in concrete.
However, a combination of gangue 15%, fly ash 10%, slag 10%, 10% silica fume, and 55% cement, number 5, produced a reduction in strength of about 8.74%.
On the average, mixes number 2, 6,10,15,17 performed better than most mixes containing a single admixture.
From the photos, the sample of the concrete 28d benchmark concrete during hydrating, the spherical fly ash grain and hydras have clear cracks on the surface of the fracture there a great deal of bare smooth fly ash balls and fly ash grains that can leave half-globe pits after they are set aside.
The hydras form the strong whole body with not hydrated grain gels.

Re-creation process model Grain Transformation of Form Space And Behavior Space Because of the abstract of function description, the product with Intellectual property rights has to be represented by form, that is patent is described by parts, components, and link relations between them.
According to the constitution of the scheme, we can obtain the optimal grain of form by the grain transformation.
For creating new combinatorial behavior solutions, the next step is to recombine basic behavior by the grain transformation.
According to the above process, we can see that forms (,and) are different partition results from coarse-grain to fine-grain.
(ii) The combinatorial explosion of solution in a design problem is avoided by the analytical strategy from coarse-grain to fine-grain.