Search results

In the largest Cu channels, grains in micrometer and in nanometer range (200-400nm) with high dislocation density are elongated along the drawing direction.
The finest Cu channels are composed of single grains elongated along the drawing axis with their grain boundaries perpendicular to the wire axis.
In larger Cu channels grains in micrometer and nanometer range are elongated along the drawing direction.
The finest Cu channels (Cu-0 and Cu-f) appear as single grains also elongated along the drawing axis.
The increase of the number of Cu/Nb interfaces associated to the presence of, probably, a Cu-nanowhiskers (Cu-f) phase could explain the origin of the high strength obtained in Cu/Nb/Cu conductors.

The microstructure of the base material is characterized by a bimodal microstructure formed by globular alpha grains (volume fraction 91%) in an intergranular beta matrix (9%).
ϑv=1-exp-btn Eq. 2 Where n is the Avrami number found in literature for the considered material set equal to 1.35 [13].
As far as the 950°C case study is regarded, a final bimodal microstructure is found, characterized by globular alpha grains and alpha/beta colonies lamellar microstructure.
A homogeneous fully lamellar structure characterized by acicular alpha grains in a beta matrix is found in the component, regardless of the observation point.
Salishchev, Strength and ductility-related properties of ultrafine grained two-phase titanium alloy produced by warm multiaxial forging, Mater.

For instance, the body-centered cubic (bcc) βTi(Al) phase (A2 structure; I m  m) can act as a ductilizing phase in TiAl alloys because it provides a high number of independent slip systems.
The powder compact, shown in Fig. 1, has a globular almost equiaxed grain structure that mainly consists of γ grains and a few (α2+γ) lamellar colonies with grain sizes of about 15 to 30 µm.
At triple points between these grains, a Nb-rich third phase can be observed, which is clearly identified as B82-ordered ωo-Ti4Al3Nb phase by X-ray diffraction [8].
Scanning electron microscope image taken in backscattered electron mode, i.e. γ grains appear in dark grey, (α2+γ) lamellar colonies appear medium grey, and the Nb-rich third phase ωo appears almost white.
It is suggested that the driving force for this rearrangement is to maximize the number of AlTi interactions which are stronger than AlNb and TiNb interactions [14,15].

The mechanical properties of MMCs can be further enhanced by decreasing the sizes of ceramic particulates and/or matrix grains from micrometer to nanometer level.
The composite obtained by this method exhibited fine grain microstructure, reasonable Al2O3 nanoparticles distribution in the matrix and low porosity.
The Al–1.5Mg–5 Al2O3 metal matrix nanocomposites showed better properties than the Al–1.5Mg base alloy for comparable grain sizes and the reactive stir mixing is best approach to reduce the porosity.
The addition of nano-B4C hybridized micron-sized Ti particles promoted localized dynamic recrystallization and result in refinement in grain size and increase in microhardness and strength values.
Lovell, Tribological Behavior of Aluminum Micro-and Nano-Composites, International Journal of Aerospace Innovations, Volume 3 · Number 3 · (2011)

Investigations are conducted into the effect of post-weld heat treatment, grain boundary features, and microstructural changes in improving cavitation resistance.
The use of friction stir welding (FSW) has a number of benefits over conventional fusion welding methods.
FSW also creates a fine-grained microstructure within the welded joint, which could improve the material's resistance to cavitation damage.
It will entail a series of experiments simulating the erosive effects of cavitation while taking into account a number of different factors, including cavitation intensity, exposure time, and temperature variations.
Materials made of copper are frequently marked with a grade number to indicate their purity or alloy composition.

The specimen that was formed by sintering Fe-TiC powders displayed a microstructure of uniformly dispersed TiC grain in a continuous metal matrix.
The titanium carbide has many applications in high technologies from mechanical and chemical industries to electronics[6], because of good properties including high melting point, high hardness, high abrasion resistance, good thermal conductivity, and high thermal shock resistance.[7-9] A number of processes were reported for synthesizing TiC powders.
In the final stage at 1373K, the presence of cleaned and activated surface is expected to enhance the grain boundary diffusion, will promote transfer of materials and thus facilitate densification and grain growth.

During the Al ultrasonic bonding process, the nanoparticles generated dispersed over the entire bonding interface and finally formed a fine grain region at the interface.
A unique microstructure, such as fine crystal grains, has been observed at the bonded interface after ultrasonic bonding [8-11].
Au nanoparticles do not have a clear contrast boundary inside the particle, suggesting that there is no grain boundary.
Acknowledgment This work was partly supported by JSPS KAKENHI Grant Number 21H01666.

However, stainless steel corrodes at high temperature (573 K ~) due to the oxidization and grain boundary corrosion.
However, oxidization and grain boundary corrosion occurs under high temperature environment and the strength of material is degraded by the surface damage.
Iron oxide is generated in initial oxidization of stainless steel and Cr carbide is also generated at the grain boundary when the austenitic stainless steel is heated at 773 ~ 1073 K or cooled gently after heating held for a long time [7].
In this paper, there was no difference of the film surface before heating for each inlet gas mass flow rate ratio, however, the number of products after heating and change of reflectivity increased with increasing the nitrogen mass flow rate ratio.

The stylus of the tester is forced into grain which placed in a container.
A number of attempts have been made to find a quantitative measure of the hardness of individual kernels or of the average hardness of a collection of kernels[3,4].
Conclusion A novel hardness tester for grain kernel was presented in the paper, and then the detection and control system was addressed in detail.

The mechanical properties of grains with different orientation are generally different.
Each nanoindentation test can measure the mechanical properties of one grain frequently, so it is very normal for the multi testing results to have wider range.
The difference of hardness between the austenite treated by electrolytic polishing and chemical etching does not exceed 8%. 1 2 3 4 150 180 210 240 270 300 1 2 3 4 5 6 7 8 9 10 (a) Number of sample treating method 1 - Mechanical polishing 2 - Electrolytic polishing 3 - Electrolytic etching 4 - Chemical etching Young's Modulus / GPa 1 2 3 4 3 4 5 6 7 8 1 2 3 4 5 6 7 8 9 10 (b) 1 - Mechanical polishing 2 - Electrolytic polishing 3 - Electrolytic etching 4 - Chemical etching Number of sample treating method Hardness / GPa 1 2 3 4 150 180 210 240 270 300 (c) 1 - Mechanical polishing 2 - Electrolytic polishing 3 - Electrolytic etching 4 - Chemical etching Number of sample treating method Young's Modulus / GPa 1 2 3 4 3 4 5 6 7 8 (d) Number of sample treating method 1 - Mechanical polishing 2 - Electrolytic polishing 3 - Electrolytic etching 4 - Chemical etching Hardness
Table 1 Young's modulus and hardness average of sample ZS and DS sample surface treating methods sample phase mechanical properties / GPa mechanical polishing electrolytic polishing electrolytic etching chemical etching E 225.5 224.8 177.1 215.0 ferrite H 5.71 4.95 4.83 4.75 E 208.0 219.4 194.2 196.6 ZS austenite H 5.61 4.94 5.70 4.57 E -- 234.6 191.9 239.2 ferrite H -- 5.85 5.12 5.24 E -- 213.53 210.9 222.4 DS austenite H -- 6.07 6.53 5.60 2 3 4 150 180 210 240 270 300 2 - Electrolytic polishing 3 - Electrolytic etching 4 - Chemical etching Young's Modulus / GPa Number of sample treating method (c) 2 3 4 3 4 5 6 7 8 Number of sample treating method (b) Hardness / GPa 2 - Electrolytic polishing 3 - Electrolytic etching 4 - Chemical etching 2 3 4 150 180 210 240 270 300 (a) 2 - Electrolytic polishing 3 - Electrolytic etching 4 - Chemical etching Number of sample
This is possibly because that the testing times for ferrite phase are limited (only 14 times), and that these testing were mainly located on the ferrite grains with soft orientation.