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The number ‘100’ stands for minimum yield strength of 100 ksi i.e. 690 MPa and the designation ‘W’ signifies it as a weathering steel implying that it can be applied in an unpainted condition.
Re-precipitation of Cu with a high number density in the extremely fast cooling rate conditions from such high TP is also likely to contribute to the high toughness values observed.
This leads to a larger number of potential sites for carbide precipitation in the former case.
As evident from the optical and SEM micrographs, the HAZ microstructures show the presence of grain boundary precipitation and precipitation within the grain as well.
At higher TP of 1300oC and 1350oC the precipitate number density is higher as compared to that of the lower TP of 850oC and 1100oC.

The possibility of joining magnesium with other materials allows a greater flexibility in designing and increasing the number of applications for light alloys.
d) Nugget c) TMAZ a) BM b) HAZ Fig. 4 Microstructure (a -BM, b -HAZ, c -TMAZ, d -nugget) of FSW weld-AZ31B (MO, 100x) In the heat affected zone (on the retreating side of the tool) there was a slight increase in the grains size, they keeping their predominantly polyhedral shape, a small number of grains being plastically deformed as a result of the welding process (Fig. 4b).
In these flow directions, the grains were strongly deformed, showing elongated shapes.
There is an alternation between the areas where the grains keep their polyhedral shape and the flow strips, with strongly deformed grains (Fig. 4c).
The fracture produced in HAZ, because of the grain size increase in the region

The average grain size obtained by sampling the size of the observed grain and calculate the average.
Also, the decreases of grain size can be seen from one of the biggest grains observed in each sample.
Decreases of the grain size proved to increase the resistivity of the sample [6].
Acknowledgments We thank to Kementerian Riset, Teknologi, dan Pendidikan Tinggi Republik Indonesia for financially funding this research through Penelitian Dasar Unggulan Perguruan Tinggi (PDUPT) grant with contract number of NKB-1590/UN2.R3.1/HKP.05.00/2019 References [1] J.
Zhou, Grain size-dependent electrical resistivity of bulk nanocrystalline Gd metals, Prog.

Platinum Group Minerals A large number of PGMs, consisting of 18 different species, were found in the deposit.
The grains are in irregular conjunction with merenskyite and platinian irarsite to form coarse compounds at the grain size ranging from 2.9μm to 4μm.
Some of the grains associate with chalcopyrite to form coarse compound grains included in serpentine, and some occur as isolated grains which are also embedded in serpentine or magnetite separately.
Paolovite[Pd2Sn] appears as inclusions or semi-inclusions in magnetite, and the grains occur as isolated grains or intergrowths with native gold.
Besides, some grains adjoin the sulphides included in gangue minerals, and the isolated grains included in magnetite can be found occasionally.

When the grain engages with the workpiece in up-cut grinding, the grain slides without cutting on the workpiece surface due to the elastic deformation of the system.
Grinding is a very complex machining process with a large number of characteristic parameters that influence each other.
Various parameters of the grinding process including the number of abrasive grains in actual contact, the number of actual cutting grains per unit area under a given depth of wheel indentation, the minimum diameter of the contacting and cutting grains, and the average volume of the chip were determined analytically and compared with the experimental results reported in the literature.
Only a small fraction of the grains participate in actual cutting while a large number of contacting grains merely rub or plow and not cut at all although there is a large number of grains on the surface of the wheel.
The simulation of the wheel topography takes account of the motion of the dressing tool, grain size, grain spacing, grain fracture and grain break-out.

It is clear that the microstructure of the original sample is composed of essentially equiaxed grains of α-Mg, and the grain size ranges from several microns to tens of microns.
In addition, a small amount of β-Mg17Al12 particles distributes mostly at grain boundaries (GBs) and rarely inside grains, and a very few of twins were detected in individual grains, which were probably yielded in the process of hot extrusion.
Besides, it should be mentioned that the amount of deformation twins in larger grains seems to be much greater than that in smaller grains, resulting probably from a longer dislocation slip path and more evident stress concentration at GB for the case of larger-sized grains.
This indicates that with increasing temperature, the number of slip systems increases, and slip deformation becomes more and more enhanced in addition to twinning deformation, particularly in the case of low strain rate (see Fig. 4c).
As for the DRX grain size, it might be governed by the work hardening rate, because work hardening taking place in the new recrystallized grains would hinder the grain growth [12].

Exfoliation corrosion occurs predominantly in products with elongated grain structures [1].
In aggressive environments, corrosion products can be formed in the vicinity of the grain/subgrain boundaries.
Days 3, 3 7, 9, 15 15, 22 31,34 F/N Number of failed specimens/total number of specimens exposed- Exposure time of the SCC test is 40 days according to ASTM 64.
We observed few differences on the propagation mode whatever the EXCO rating: grain boundary dissolution, followed by the attack of adjacent grains and growing of oxides.
The results presented above being carefully applied on the same grain structure, the sensitivities to IGC have been varied with different grain boundary decoration resulting from different quench rates and different heat treatments.

Besides, the average grain size and solid fraction increased with the decreasing of pouring temperature.
Furthermore, in the eutectic matrix (dark gray region), a large number of micro primary grains with an average grain size of several μm are also found.
When poured at 600℃, the average grain size and solid fraction is 29.44μm and 0.435, respectively.
Fig. 9 shows the HPDC average grain size and solid fraction of the ADC12 alloy.
With the pouring temperature of 605℃, its solid fraction is 0.316 and average grain size is 10.03μm.

All the films display a very smooth, uniform grain size and void-free surface.
The grain size shows an evident increasing tendency with substrate temperature.
It is evident that the substrate temperature changes both the grain size and the grain shape remarkably, leading to the remarkable improvement of films crystallization.
The surface roughnesses can be a barometer for the grain sizes and the number of grain boundaries.
The variation of mobility is regarded as the result of better crystallinity of the films, which promotes the increase in the grain size and reduce grain boundary scattering and increase conductivity.

The fine grains and strain-induced martensite were fabricated in the surface layer of AISI 304 austenitic stainless steel by shot peening treatment.
In general aspects, the enhanced nitriding kinetics could be attributed to abundant grain boundaries and non-equilibrium defects produced by severe deformation prior to nitriding.
Samples were identified as SP10-SP36, SS10-SS36, with the initial letters indicating the treatment method, and the numbers, the treatment hours.
In our earlier study, after shot peening of SS304, a relatively coarse-grained structure is transformed into a fine-grained one and different systems of slip bands can be observed for most of the grains [13].The surface layer of shot peening samples consist of mainly a’-martensite with only a fraction of austenite.
Because the chromium nitrides prefer to deposit along the slip bands and grain boundaries, the black precipitates in SP10 and SP36 are not as apparently to be observed as in SS36 ( see Fig.1).