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Xu et al.[10] found that the strength of the China low-activation martensitic steel had no significant change during the thermal exposure at 550 °C up to 10,000 hours, while the subgrains were formed and the grain coarsened during thermal aging leading to 46°C increase in DBTT of this material during thermal aging.
Sahoo et al.[11] reported that the decrease in tensile strength and the increase in tensile ductility and DBTT of reduced activation ferritic-martensitic steel were observed after thermal aging at 500 °C for 5,000 hours owing to the coarsenomg of martensite lath and dislocation cell with in the lath and M23C6 carbides on the grain and lath boundaries.
A large number of related studies were focused on the tensile and impact properties of ASME SA508 and SA533, however, there is a lack of the related research of French RCC-M 16MND5.
Grain Boundary Phosphorus Segregation in Thermally Aged Low Alloy Steels, Journal of Nuclear Science & Technology. 43 (2006) 785-93

A characteristic feature of MCC, having a highly developed hydrophilic surface with a large number of active hydroxyl groups, is its ability to swell, disperse and form relatively stable thixotropic hydrogels with water-retaining properties [20].
When these substances are introduced into the mineral binders together with water, adsorption and intermolecular adhesion forces bring to their orientation around the grains of the binder, forming an adsorption layer.
At the same time, this shell hinders water access to the grains of the binder, resulting in inhibition of hydrolysis and binder hydration [21].
Kuzmin, Fine-Grained Concrete of Composite Binder, IOP Conference Series: Materials Science and Engineering. 262(1) (2017) 012025

The SEM analysis for positions 1 and 4 of mechanical properties was showed that the specimens of # 4 and # 1-1 were ductile fractures, with a large number of small tearing edges, abundant fiber areas with small and uniform silicon particles rounded.
Metallographic analysis near the fracture area of the specimens was shown that the grain size was about 79 μm for 1-1# specimen or 91μm for 4# specimen (the transversal method was used to calculate the grain size), and the silicon particles were fine and uniformly distributed around the aluminum matrix.
[3] Min Luo, Daquan Li, Wenying Qu, Xiaokang Liang, Jianzhong Fan, Effects of Cooling Rate and Grain Refiner on Semi-solid Rheocasting Slurries of Al–Zn–Mg Alloy, In Advances in Materials Processing, 2018; pp 829-837

The backward extrusion method has been successfully utilized as a final processing route to generate fine grained products [4,5].
Subsequently, the geometry model was meshed with quadrilateral element shown in Fig. 1 and the total number of element and node of workpiece is 5000 and 5151, respectively.
Consequently that the severe shear plastic deformation in the channel of punch and wall of bottom die is helpful for the grain size refining.
Vinogradov, Extreme grain refinement by severe plastic deformation: a wealth of challenging science, Acta.

Fig. 3(b) SAED pattern of 50 h refluxed MgO annealed at 900 0 C for 13 h Table 1 Comparison of d-spacing and grain size from XRD and SAED 2q FWHM d (Å) hkl plane Average grain size (nm) XRD SAED XRD TEM 42.725 0.420 2.1147 2.0210 (200) 27 28 61.938 0.485 1.4970 1.4245 (220) 74.186 0.233 1.2772 1.2375 (311) Microstructural studies using TEM.Figure 3(a-b) shows the TEM and SAED images of nanocrystalline MgO annealed at 900°C in O2 atmosphere for 13 h sample exhibited an average crystalline size of 28 nm with the cubic phase of MgO, which is also confirmed by XRD study (Fig.2(C)).
Fig. 7(a) TGA traces of 50 h refluxed sample, (a) as-prepared (b) annealed at 900 0 C /13 h Fig. 7(b) DSC traces of 50 h refluxed sample (a) as prepared and (b) annealed at 900 0 C /13 h Optical studies.The FTIR analysis of the as-prepared sample was carried out in the wave number range 400-4000 cm-1 and its spectrum is shown in Figure 8(a).
Fig. 10 Z-scan of the MgO nanoparticle exhibiting its optical limiting property Conclusions In this work, we have successfully synthesized nanocrystalline MgO using the sol-gel method with average grain size of 28 nm.

In order to optimize the size, the number and the location of CW blocks, 3-D finite element models have been developed. 3D non-linear finite element models have been developed to simulate the pre-camber of Glulam beams locally reinforced by compressed wood blocks.
However, the way to reinforce the glulam beam needs to be optimised to find out the effective size, location and number of the CW blocks.
To simplify the model, some parameters were neglected, such as distortion in the grain, knots, temperature and density variation.
Conclusions 3-D non finite element models have been developed to investigate the reasonable size, number and location of CW blocks to be inserted in the Glulam beam which could generate effective pre-camber.The final models developed have been validated against the corresponding experimental results in terms of the pre-camber deflection and the initial strains (and therefore stresses) The predicted extreme fibre strains (and therefore stresses) of all pre-stressed glulam beams have showed good correlation with the experimental results.
[8] Svenson S, Toratti T, Mechanical Response of wood perpendicular to grain when subject to changes of humidity, Wood Science and Technology, Springer- Verlag, vol.36; pp:145-156, 2002

Furthermore, electronic ceramics undergo high-temperature treatments which influence not only the bulk stoichiometry but also the local composition of constricted regions along grain boundaries.
In spite of their complexity, these systems offer a variety of challenging opportunities for a vast number of technological applications, provided one is able to manage properly all the variables, which is not an easy task however.
It was really a privilege to have the immediate assistance of a number of talented people working in the area as, without their collaboration, this book would never have had the chance to appear.

A huge number of pits form on the composite than on their respective wrought alloys.
They were able to prepare Al matrix composites augmented with Si through pre-treatment of aluminum molds and SiC grains.
It was observed that SiC grains substantially enhanced its hardness, elastic modulus, tensile stress and compressive strength.
Some intermetallics substantially reduces the resilience of Al alloys to confined degradation (grains with Cu and Fe in 2xxx and 1xxx series Al alloys) while some do not.
The reaction of the intermetallics is subject to potential difference between the grains and the Al matrix.

It was found that it has a huge economic benefits in preparing the cement with gas quenching steel slag.The results showed that the content of f-CaO in slag particles less than 2mm were no more than 2.7% and there exists a well proportional relation between it and the grain size; the grindability of gas quenching steel slag is much better than heat-stew steel slag; what's more,because of the high hydration activity of gas quenching steel slag, it can be produced the perfect steel slag cement with excellent hydration, stability and strength.
But the utilization of steel slag of domestic currently is still very low, resulting in a large number of steel slag accumulation, It not only takes up a lot of land resources and pollute the environment seriously , but also wastes lots of resources.
The rapid cooling technology of liquid steel slag can be made when the temperature drops below 500 as the steel slag is 15m away the nozzle within 1s.Fig.1 shows a gas quenching graining device of liquid steel slag.
Fig.1 gas quenching graining device of liquid steel slag Fig 2 The change of steel slag temperature with distance and time Table 1 shows the particle size distribution of gas quenching steel slag where we can see that the sizes of steel slag particles are mainly 1-2mm and 0.1-0.5mm.

Again, this can be related to the microstructural differences caused by the semi-solid processing, able to create a smaller number of microcells.
The conventionally cast sample experienced the strongest damage, as evident by the high number of large and deep pits (Fig. 8a-c).
On the contrary, the globular microstructure showed higher erosion resistance, as demonstrated by the more limited number of smaller and less deep pits (Fig. 8d-f).
Hellawell, Grain evoluation in conventional rheocasting, in 4th International Conference on Semi-Solid Processing of Alloys and Composites, Sheffield - UK, 1996
Emamy, Investigation of the effect of Al–5Ti–1B grain refiner on dry sliding wear behavior of an Al–Zn–Mg–Cu alloy formed by strain-induced melt activation process, Materials and Design, Vol. 46, pp. 766-775, 2013