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When the solution treatment temperature was up to 1200°C, the carbide dissolution completed, grain boundaries became straight, and the grains grew obviously.
For the effect of solution treatment temperature on mechanical properties of Cr20Ni32AlTi there are two main factors: the degree of recrystallization and the number and the distribution of carbides.
In the solution treatment process, recovery and recrystallization caused by grain boundary migration, while grain boundary migration caused by mutual annexation, thus grain growth occurs.
Meanwhile grain size is fine.
Grain refinement also increases the strength of alloy.

The results indicated that Al microparticles slowly dissolved into nickel grain to form an ultrafine-grained Ni3Al/NiAl composite with micro-sized pores dispersion due to volume shrinkage.
After 3h annealing, both the number and size of black Al microparticles significantly decreased, but gray areas with micro-sized voids dispersion around Al microparticles appeared, as seen in Fig.2c.
From Fig.2d, it can be found that the grain size increased to the averaged ~220 nm.
Thus, the number of alumina nuclei formed on the A-EMC Ni-Al increased with the increasing of annealing times.
In another word, the number and size of voids gradually decreased with the increasing of annealing time, as seen in Fig.2.

Most of these effects are related to the nanometer-scaled grain size.
Carbon will pin dislocations and grain boundaries, slowing down the dynamic recovery process.
This is in contrast to the ductility which is limited by the number of inclusions.
The number of inclusions and the purity content are correlated.
An increasing amount of impurities leads to a higher number of non-metallic inclusions, restricting the intrinsic ductility.

The numbers and locations of the thermocouples are also shown in Fig. 1.
The structure of the specimen in the as cast condition exhibits coarse equiaxed grains in the center and finer grains in the chill zone close to the die wall.
By increasing vibrations’ intensity up to 20g and reducing the grain size, a higher number of ceramic particles is detected at grain boundaries rather than in the interdendritic channels (Fig. 10b).
At the highest vibrations’ conditions, with a grain size about 100 µm, the reinforcement exclusively segregates at grain boundaries (Fig. 10c).
While the SiC particles are preferably entrapped in the interdendritic regions in the castings solidified without vibrations, by increasing vibrations’ intensity and reducing the grain size, a higher number of ceramic particles is detected at grain boundaries rather than in the interdendritic channels

Species and yield At maturity, each treatment was investigated for amount of valid spikes, spike length, fruit rate, weight of 1000 grains and total weight of grains.
In the whole growth period, tillers number for drought treatment in heading stage or milky maturity stage was very close to CK (Fig. 3d and Fig. 3e).
Fig 3 Change process of the tillers number of each treatment and plant height of CK Effects of soil moisture potential controlling on rice quality The rice quality of each treatment was determined by Grain analyzer Infratec 1241 and Presentation-quality rice discriminant ES-1000.
In addition, water stress lowered the rate of brown rice, reduced the content of amylose and free fatty acid, increased the percentage of chalky grains and chalkiness degree, but had no significant effects on grain length and grain width.
The results obtained by some scholars [15] also believe that water stress had little effect on the grain shape, but increased the percentage of chalky grains and chalkiness degree, then damaged the appearance quality of rice.

These metallographic shows M7C3 grains become larger when the distance is increasing from the fusion line.
Then, different grain began to form in the surfacing layer.
A large number of carbides began to form at the same time.
This is because a large number of M7C3 and TiC ceramic hard phase were formed in the surfacing layer.
The concentration gradient of C between the surfacing layer and base metal is big, because Fe-Cr-Ti-C alloy contains large number of C.

Further, grain structure and grain boundary character are analyzed in detail to discuss the deformation mechanism.
Grain Structure.
They are distinguished by number of high KAM points.
Grain Boundary Character.
The fine grains remained during the deformation through grain boundary sliding or dynamic recrystallization.

The average grain size increased from the original DRX mean grain size of 18 mm to about 30 mm at 60 s holding time, where the maximum softening was achieved.
Beyond 60 s, the grain size only changed slightly through normal grain growth (Fig. 2b).
The ODFs corresponding to the SRX grains formed at different holding times showed that these grains had essentially random texture (Figs. 3c, 3d).
It has been suggested that such arrangements result from a limited number of highly-stressed slip systems frequently concentrated on one slip plane [11].
By contrast, the substructure character of the DRX grains was remarkably different from the deformed matrix regardless of grain orientation.

Compared to Al-containing ODS steel, the finer grains of Al-free ODS steel are due to the formation of smaller coherent oxide particles which suppress the steel's grain growth.
Alloying element Ti was added in the ODS steels to decrease the size of dispersed oxide particles and increase their number density in the steel matrix.
This is consistent with smaller grain size of Al-free ODS steel [9].
As for the effect of grain refinement, the ion diffusion along grain boundaries is considered to be critical in the present ODS steels because the oxide scales of the previous ODS steels have been shown to grow exclusively by oxygen grain boundary transport [13, 18].
Compared to Al-containing ODS steel, the finer grains of Al-free ODS steel are due to the formation of smaller coherent oxide particles which suppress the steel's grain growth.

This process, while being expensive to implement due to high tooling and raw material costs, saves a significant amount of money over the life of an airplane program due to greatly reducing the number of detail parts, which reduces the amount of expensive assembly that is required.
This monolithic technology will be used to reduce part count as well as the number of fasteners, assembly time, and weight all of which lead to cost savings for the product.
This fine grain material will also diffusion bond to standard grain alpha-beta alloys, as shown in Fig. 8, at 775 °C using the same time and pressure conditions [8].
These standard grain alloys typically require about 900 to 925 °C to fully diffusion bond.
At this temperature, the fine grain material will not only diffusion bond to itself but will also bond to standard grain alpha-beta alloys using the same time and pressure conditions.