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The I-phase (Mg3Zn6Y) has a number of exceptional characteristics including high hardness, low surface energy and excellent high-temperature plasticity [1,3].
When the acoustic power density is at a low level (3 W/mL), most of a-Mg grains are spherical while a small number of them are rosette-like with some dendritic arms still existing.
As the acoustic power density increases to 6 W/mL, a-Mg grains are converted into fine and spherical grains.
A large number of cavitation bubbles form and grow when the melt is subjected to local tensile stress.
Therefore, a large number of nuclei form around the cavitation bubbles.

Table 1: Required values for the documentation of forging strokes · Timestamp · Number of pass · Number of stroke · Die length · Die radius · Length before/after stroke · Width before/after stroke · Height before/after stroke · Position of the manipulator · Rotation angle of the manipulator · Transportation time to press · Indicator for length measurement · Furnace temperature · Surface temperature The data management in FAST is split into three arrays.
During the cooling process, grain growth takes place, increasing the average austenitic grain size to about 135 µm.
At the faster cooling edges, the resulting grain size is lower.
Fig. 9: Recrystallized microstructure fractions and grain size after the 1st pass of process 1 in the core fibre of the ingot (node number corresponding to position in the workpiece) As the data in FAST is stored for every stroke in the process, a point tracking can easily be extracted from the calculated data.
It can be concluded, that some strokes are influencing the minimum grain size, others do only have a slight influence on the average grain size, which is a result of the low fraction part of the newly recrystallized grains.

Conductivity is measured using the QJ36-type bridge arms, sample size is 200mm × 3mm × 1mm, an accuracy of ± 0.05%; hardness number is tested in the HVS-1000 micro hardness tester at 100g load for 20s; Tensile strength tested by using CSS-44100 universal tensile machine.
The addition of rare earth compound with some low melting point impurities in copper and these compounds act of crystals core dispersed in the melt, those significantly increased the number of grains and the grain thus be refined. 2) clean the grain boundary Because the metallurgy atmosphere present oxidizability and the hydrogen content is high during non-vacuum melting process of Cu-Cr-Zr alloy, the metal components form oxide and hydride easily.
The compound that didn’t come-up during solidification distributes in grain boundaries.
Therefore, it is necessary to add certain content of La and Ce to clear grain boundary.
Because the rare earth is provided with the effect of degassing, dedusting, fining grain and clearing grain boundaries and so on, the change of optical microstructure should have some effect on alloy properties.

At the same time, the redundant Zn bonds with Ca and Mg to form Ca2Mg6Zn3, which distributes in the grain interior and grain boundary.
However, for the MZC0.7Zr alloy specimens, some of the superfluous Zr particles congregate at grain boundary as impurities to disrupt the continuity of the secondary phases, which can speed up corrosion spreading from one grain to another grain.
The addition of Zr refined the grains and did not form new phase.
With the increment of Zr content, the number of Zr particle distributed along the the grain boundary was increased. 2.
The result was attributed to the best combination of the refinement in the grain sizes, continuous distributions of the secondary phases and less number of Zr particles.

The average grain diameter and standard deviation values obtained by counting for a number of crystal grains, with constant thickness, was also evaluated from TEM analysis.
The smaller and more uniform is grain size, the higher is Hc, and the lower is Ms.
Such extremely small grains may cause super-paramagnetic behavior of the film.
The constant C denotes the total number of atoms per unit volume.
The structure was designed to obtain a fine grain size of the magnetic layer.

Grain size is shown to have a significant effect on cracking.
They are intergranular by nature and form along the grain boundaries.
Two different grain sizes were used for the CMT work to test the grain size effect, these are 3.5mm and 4.9mm average diameter.
The average grain diameter of the material used in these welds is the 3.5mm size.
It also shows that there is a small effect of grain size, with the larger grain sized material showing more cracking compared to the smaller grain size. 21.82% 2000 2500 3000 3500 4000 4500 5000 5500 100 200 300 400 500 600 700 Small grain size Large grain size ACL (µm) Arc Power (W ) 0.30 0.35 0.40 0.45 0.50 0.55 0.60 100 200 300 400 500 600 700 Small grain size Large grain size ACL (µm) Travel Speed (m/min) 23.64% 34.55% 20.00% a) b) a) b) a) 1 -4 -2 0 2 4 6 8 Difference (mm) Power (kW) Cracking (Before - After) Not cracked - Not cracked Not cracked - Cracked Cracked - Not cracked Cracked - Cracked b) Lowest cracking Highest cracking A small number of the laser samples showed evidence of solidification cracking in the FZ.

The maximum number of passes obtained in the T7 condition was twelve.
With increasing back-pressure the number of passes without failure increased proportionally for all conditions.
The mechanical properties of material processed by the same number of ECAE passes at different level of back-pressure were different.
As shown back-pressure also effects the grain size during grain refinement resulting from ECAE.
F., Ultrafine-grained Al-5 wt.

Their melting points and densities are quite different, which leads to serious component segregation during solidification of the alloy and a large number of shrinkage defects.
There are a large number of defects in the ingot, and the diameter of some defects can reach more than 200um.
Sn is evenly distributed in the α-Al grain boundary in the form of a network.
Most of the Sn phases are twisted and a large number of Sn phases are broken.
In addition to the network distribution of Sn phases at the grain boundaries of the Al alloy matrix, there are also a large number of granular Sn phases inside the grains.

A modulus of elasticity of 225 GPa and a Poisson number of 0.28 had been used for calculating residual stresses for the (211) reflection.
The results were still quite noisy, which was attributed to bad grain statistics.
The number of diffracting grains is small in this case not only because of the small beam size but also because of the small divergence of the beam coming from an undulator.
Since beam intensities are much higher than at neutron instruments, a large number of points can be measured within short time.
Moreover, in many cases measures have to be taken to improve the grain statistics.

And the failure mechanism is that NiMoB crystallized and grains grew after annealing at high temperature, a large number of Cu grains passed through NiMoB film via grain boundaries and then reacted with Si substrate and oxygen, causing the generation of highly resistive Cu4Si and CuO.
In Fig.4(d), grains were larger after annealing at 500°C.
There were many small grains generated in the grain boundary.
Fig.4(e) shows the surface appearance of NiMoB/Cu/NiMoB/SiO2/Si films after annealing at 550°C, it could be seen that the grains were so large, small grains which generated after annealing at 500°C grew up and generated more, which indicated that a lot of Cu grains have passed through the diffusion barrier layer, and the NiMoB film failed completely.
The failure mechanism of NiMoB film is that the barrier layer crystallized and generated large grains, a lot of Cu grains passed through diffusion barrier layer by grain boundaries, and reacted with the Si substrate and O2 to generate Cu4Si and CuO with high resistivity.