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Cooling to 460 ℃ and 400 ℃ follow by quenching, precipitates nucleated discontinuously on the grain boundaries, no precipitates was found within the grains.
The precipitates were found near the grain boundaries when quenching from 350 ℃, and precipitated uniformly within the center of the grains when quenching from 250 ℃.
The industrial processing of high strength 7050 thick plate involves a number of steps including melting, casting, homogenization, preheating, hot rolling, solution and ageing, etc.
The nominal composition of the alloy is Al-6.30Zn-2.30Mg-2.20Cu-0.11Zr-0.05Ti-0.06Si-0.12Fe (numbers indicate wt.%).
(2) Cooling to 460 ℃ and 400 ℃ follow by quenching, precipitates nucleated discontinuously on the grain boundaries, no precipitates was found within the grains

These monolithic technologies are 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.
Even though either of these processes would allow the number of components to be reduced by combining details, it was decided to keep the same number of major parts.
A fine grain version of 6Al-4V, with a grain size of about 1 µm, has been jointly developed by Verknaya Salda Metallurgical Production Association, VSMPO, in Russia and Boeing.
This fine grain material will also diffusion bond to standard grain alpha-beta alloys, as shown in Fig. 5, at 775°C using the same time and pressure conditions.
Fig. 6 Representative SPF heat shield details produced using fine grain 6Al-4V.

Grain Boundary Velocities.
Sub-grain Boundary Growth.
The sub-grain mobilities were estimated from the average growth rates of large numbers of sub-grains during more standard annealing experiments outside the SEM.
Grain boundary velocities and mobilities.
Analysis of Grain boundary mobilities.

The films grow with granular grains.
The Ni33Fe67 film consists of irregular shaped grains and a few large triangular grains.
The Ni33Fe67 film consists of a large number of irregular shaped grains and a few large triangular grains.
It is attributed to the fact that a large number of defects such as vacancies, impurities and grain boundaries exist in the film compared with the bulk.
In general, a large number of defects existing in the film result in a low density of the film relative to the bulk.

The same evolution is noticed for the Σ3 grain boundaries inside the γ phase.
For highest strained samples, the spatial resolution is not always compatible with the grain or sub-grain size.
Grain size distribution in terms of rolling reduction.
This is particularly true for the 60° grain boundary misorientations (Fig. 5b) which can be associated to the twin Σ3 grain boundary observed in the γ phase (the Σ3 percentage presented in Fig. 5b is calculated regarding the overall CSL GB number (Σ3 to Σ29)).
Indeed, Fig. 6a shows undeformed grains since the orientation remains constant inside any individual grain (Fig. 6a and 6c-top).

The AFM results for all ratios indicate that as the number of pulses increase, the higher the resulted grain size.
The average grain size was between (58.82 nm) to (95.75nm).
It's seen that as the number of pulses increase, the average grain size increase due to cluster formation.
Figure 1 below demonstrates the AFM results while Table 2 sums up the grain sizes.
The AFM results for all ratios indicate that as the number of pulses increase, the higher the resulted grain size.

To study the influence of strain path, samples of an aluminium-1%manganese alloy have been subjected to a number of strain path changes.
Fig 2(a) shows the orientation map with an overlay of the grain boundaries thick lines indicating high angle grain boundaries (HAGB), >15°, and the thin lines low angle grain boundaries (LAGB), 1-15°.
The majority of the scan is contained within one grain with a large amount of sub structure visible in the grain.
As can be seen there are a number of large second phase particles in the material which appear to have varying chemical compositions with some containing only manganese, some silicon only and some mixed.
The sub-grain sizes and aspect ratios are shown in Table 2.

Since isostatic pressing can densify the perovskite film, it may also reduce the number of grain boundary defects in the perovskite film, thus enhancing its thermal stability.
The CIP treatment effectively densified the PMMA-MAPbI3 film, reducing the number of GBs within the film.
The pristine control film consisted of densely packed small perovskite grains.
Despite the presence of PbI2 nanorods, the CIP-treated 5 h film still retained many of its perovskite grains.
By compressing the film under high pressure, CIP densified the film and reduced the number of GBs acting as defect sites.

Samples were deformed for several numbers of revolutions up to N=75 and then aged at 200 °C in air for up to 96 h followed by quenching in ice water.
The grain size of the Al matrix was measured using TEM.
The equivalent strain introduced by HPT processing is a function of the number of revolutions N, the distance from the disk center r, and the thickness during HPT processing t [7]: ε = 2πNr / √3t
This grain size was rather stable up to subsequent aging at 200 °C such that the grain size was ~140 nm for aging up to 0.25 h and ~180 nm for 24 h.
The sample exhibits a recrystallized structure with the grain size increased to ~400 nm and grain boundaries well-defined as shown by the image in Fig. 6(a).

Then the alloys were subjected to ECAP in a tool with a channel intersection angle of 45° at a temperature of 450 °C along the BC route [20], the number of cycles was 6.
ECAP provides the formation of a homogeneous sub-fine-grained structure in the alloys, while the average grain size, decreasing 100-200 times, is 0.3-0.5 microns.
According to TEM data, grain boundaries free of dislocations are observed in the coarse-grained state.
After ECAP, a complex diffraction contrast is observed at the grain boundaries, which indirectly indicates an increase in the density of dislocations at the grain boundaries.
During mechanical tests, it was found that in the coarse-grained state, the tensile strength of the Ti49.5Ni50.5 alloy is 720 MPa, and after the ECAP increases with the number of passes and reaches a maximum (1350 MPa) for 6 passes, which is almost 90% higher than in the coarse-grained quenched state (Fig. 2).