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It describes the advantages of using HIP product forms to combine separate sections of straight pipe and elbows and, in so doing, reducing the number of structural plant welds.
Structural integrity benefits are described, such as improved grain structure, improved mechanical properties, and enhanced capability for ultrasonic inspection.
Benefits have been realised with regard to reduced lead times, unit cost savings due to reduced material requirements, inspection benefits due to the finer grain size achieved allowing more searching ultrasonic inspections, and structural integrity improvements, again due to the finer grain structure and the lack of defects associated with casting, forging and fabrication processes.
This region (Fig 4) consists of finer grain size (ASTM 6) material and has a potential benefit in relation to resistance to Environmentally Assisted Cracking.
Fig. 4 Micro Structure of the Micro Hardness Test Piece Showing a Finer Grain Structure Towards the as-HIPed Edge Fig. 3.

With an increasing number of different types of nanocoated particle and growing understanding of the resulting properties owing to the small particles that are embedded in a second phase, new and interesting applications should become available.
The diffusion barrier that hinders grain growth and densification has been put deliberately at the grain surface during the synthesis process, and is consequently located at the grain boundaries after compaction.
This is because the absorption of the electrons in the amorphous alumina layer is weaker than zirconia core (difference in atomic number between aluminium and zirconium)[6].
This suggests that alumina segregates at the grain boundaries and acts as a barrier for diffusion.
For gaining ultrafine grain sizes in a dense ceramic, nano-Al2O3-coated ZrO2 are better suited.

They suggest there may be large strain in manganite grain boundaries and believe these characters are due to the grain boundary contribution.
The finer grains bring more grain boundaries, and more grain boundaries could bring different percolative phases associated with the disorder and inhomogeneity in the system.
Infrared absorption spectrum Fig. 5 (a) shows the infrared (IR) absorption spectrum of LSMO2 at room temperature with wave numbers between 400 and 800 cm-1.
The effect of grain boundaries is obvious as seen from R (H).
The finer grains probably bring more grain boundaries in LSMO2.

(2) Here, mij, aij, wij, Dfij are parameters depending on the combination of i and j, and n is the number of phases for which fi is non-zero.
Grain growth and recrystallization processes are simulated successfully using this model, but it has a difficulty to stable, or at least quasi-stable, state of polycrystalline structure; i.e. grain coarsening occurs continuously until all grains are unified.
The author proposed a modified model [6-8] which stops the continual grain coarsening to achieve stable state under assumption that all grains reach stable state when the size of the adjacent grains are equalized.
A number of bubbles are independently formed and get together, and then the space is divided into space-filling cells.
Uehara: Grain-size equalization model using multi-phase-field model, Proc. 7th Int.

A number of studies have proved the possibility of obtaining ultra-fine-grained structure by SPD methods [13-16].
When rolled with a pressure of 50 MPa, the percentage of grains with small-angle boundaries increases to 96% (depth 50 microns).
After that, preliminary and final grinding with sandpaper with a small grain was carried out.
Thus, in the study [23] as a result of SPD MR-roller confirmed the presence of ultra-fine-grained structure in the thin surface layer of steel 45. 4.
R. 2018 Improving the performance properties of titanium alloy on the basis of grinding grain microstructure and surface modification. : dis. ...

Introduction In recent years, ultrafine-grained (UFG) materials have attracted more attentions due to its excellent physical, chemical and mechanical properties.
The "top-down" approach is dependent upon taking a bulk solid with a relatively coarse grain size and processing the solid to produce a UFG microstructure through heavy straining or shock loading.
The maximum load after different number of compressions with different friction coefficients is shown in Fig. 2.
The maximum load increases with the friction coefficient under the same number of compression condition.
The maximum damage value and maximum principal stress increase with the friction coefficient under the same number of compression condition.

Tin oxide nano grains were deposited on the pore surface of the membrane for modification by the in situ synthesis method [14].
For the modified membrane, SnO2 nano grains (about 5 nm) are successfully distributed on the pore surface of the membrane by in situ synthesis method.
The results can be explained as follows [15]: an electric field is formed in the membrane pores since SnO2 nano grains have electronegativity.
Accordingly, the number of water molecular clusters decreases when the pure water passes through the pores of the modified membrane, which lessens the viscosity (μ) of the pure water.
The effect of SnO2 nano grains on the flow behavior of pure water in the membrane pores is described in Fig. 4.

The CT images at each stage, the CT numbers and the comparison among different sections in the specimens were obtained.
After that, when original crack deformed and surrounding grains began to change at meso-level, the dynamic scanning was conducted until specimen failure took place.
In each figure, images of one layer at 9 scans are summarized, and the numbering sequence of the figures is from top to bottom.
Because the focus is on the propagation law of the original crack, and the CT number can reflect the density level of the mass, the statistic analysis was carried out on the CT number.
When damage occurs, the CT number drops unceasingly with the propagation of the crack.

The microstructures of the quenched steels consisted of fine martensite, a small amount of blocky ferrite and secondary particles except quenching at 1150°C, where the microstructures of the quenched steels consisted of coarse martensite and large number of blocky ferrite.
After heat treatment at 1150°C for 30min, secondary particles were fully dissolved into the matrix and the grain size of austenite increased significantly, which led to the coarsening of martensite after quenching and the formation of large number of blocky ferrite due to the increase of chromium level in the matrix which can expand ferrite phase region.
The hardness of the quenched steel continuously increases with quenching temperature up to 1100°C because the increase of chromium content in the matrix gives rise to the increase of the amount of twin martensite and then drop observably owing to the formation of large number of blocky ferrite.
The secondary particles were present not only at grain-boundaries, but also randomly distributed in grain interiors, which intimates that the segregation occurring in the annealed steel was entirely eliminated after heat treatment at 1070°C for 30min.
At the same time, the grain size of austenite increased significantly, which led to the coarsening of martensite after quenching and the formation of large number of blocky ferrite due to the increase of chromium level in the matrix.

Then, to keep the number of fine particles at high level, it is necessary to use fine grained cement compatible additives which do not chemically participate on hydration process – at least not too much – and thus do not increase the resulting strength.
The main reason for the use of fly ash was due to its spherically shape grains, so the required fresh SCC’s rheological properties could be accomplished.
The mixing ratio of the individual fractions was 53:14:33% and the size of the largest grain was 16 mm.
Therefore, it can be expected that larger quantity of water and superplasticising admixture for the wetting of grains will be needed.