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Currently only a limited number of metal alloys can be processed by AM.
The higher the G/M ratio the finer the final grain size ratio and vice versa.
The Gas Atomization system with the best configuration currently available is able to produce the grain size fraction useful for AM (SLM) with a maximum yield not higher than 50%.
The main goal of CSM work is to increase the yield from 50% to 65% by correlating process parameters with the grain size in the AM range The effect of gas pressure has been investigated: the increase in atomization pressure leads to a finer powder with an increase in the SLM granulometric yield.

Rapidly solidified aluminium grades characterised by their ultra-fine grains can be used to replace traditional optical aluminium such as 6061-T6 which has coarse microstructure when making optics.
The literature states that these grades in general exhibit highly interesting physical qualities such as finer grain structures, high strength and superior thermal conductivity when compared to traditional optical aluminium such as 6061-T6.
It can be that said a number of factors need to be considered in order to achieve longer tool life; amongst those is the optimization of the mould material.

The effects of the structures, temperature of calcination, volume fraction of Si3N4 powder and number of the infiltrations on the local mechanical properties were investigated.
The samples, which are labeled with number 1, were prepared by the infiltration of the silicon nitride suspension with the volume fraction of 40 % Si3N4 into the polyurethane foam.
The samples, labeled as number 2, were prepared in the same way as the samples 1; however they were pre-sintered at the 1100 °C for 1 hour.
The numbers 48 and 62 constitute a pore size of the polyurethane foams.
All investigated samples were grinded and polished using SiC papers with the grain size of 500, 800, 1200 and 2500 with water.

Columnar grains oriented from the boundary to the center of the melt pool can be found, as well as a fine equiaxed structure along the melt pool boundaries and near the edges of samples.
Austenite grains are found preferably close to the sample surface (Fig. 2e), while martensite increases moving inward (Fig. 2f).
Ni3Ti2 presence is confirmed by the morphology, i.e. plate and indefinite block shape located both at grain boundaries and within the grains [23].
Funding This work was supported by the research grant from Enterprise Ireland under grant number DT 2019 0076 and Science Foundation Ireland (SFI) under grant number 16/RC/3872 and is co-funded under the European Regional Development Fund.
Cui, Effect of number of crowns on the crush resistance in open-cell stent design, J. of Mechanics of Mater. and Structures 15 (1) (2020) 75-86 [26] D.

There have been numbers of Chinese studies regarding utilizations of the Mg slag.
The borate particles in the slag should be in contact with Ca2SiO4 grains and be incorporated in the Ca2SiO4 crystal structure to form a solid solution with Ca2SiO4 phase, hence being able to stabilize the higher temperature Ca2SiO4 polymorphs to ambient temperature.
During the sintering, some parts of B2O3 in the borate particles may need to contact the Ca2SiO4 grains via diffusion.
By referring to the mapping results, it can be deduced that Ca2SiO4 grains have occupied a large area in the micrograph and have formed solid solution with both Na and B ions, which are evenly distributed in the same area.
The mapping in Fig. 8 demonstrates an existence of MgO containing mineral phases near the lower, right corner and in the area occupied by the Ca2SiO4 grains.

The total number of time origins of about 1.8×107 were used for calculations of the autocorrelation functions of the interdiffusion flux Ccct, and the cross-correlation functions between the interdiffusion flux and the total heat flux.
Specifically, at the post-processing stage, the coarse-grained surfaces Qc*=Qc*c1,T, Hc=Hcc1,T and Qc*'=Qc*'c1,T were generated in the beginning using simulation data for the three Ni25Al75, Ni50Al50 and Ni75Al25 alloy compositions.
The symbols indicate the simulation results which are used for the coarse-grained mapping of Qc*.
The symbols indicate the simulation results which are used for the coarse-grained mapping of Hc.
The symbols indicate the simulation results which are used for the coarse-grained mapping of Qc*'.

Silver ions are reduced to be fine-grain metallic silver film then precipitate on a glass substrate.
Silicon carbide paper grinding: a glass slide was grinded with different number of grinding paper (No.240, 320 and 600) for 5 minutes with 150 rpm.
The more the lower number was used, the more the roughness was observed (Fig.3g, 3h and 3i).
These grains were connected to each other and a continuous film was formed.
In other words, it was implied that surface roughness adhered these silver grains together via Van der Waals.

In the current study, the CNTs were thoroughly ingested into the chromium grains, strengthening the layer of chromium, and filled in micron-sized crevices and holes.
Some MWCNTs were desquamated from the chromium matrix as chromium was gently etched away during this corrosion process, while some MWCNTs were still visible at grain/grain interfaces.
Varadan, Mechanical properties of carbon nanotube/polymer composites, Scientific Reports volume 4, Article number: 6479, 2014, pp. 1-8 [14] J.
Rantel, Load transfer and deformation mechanisms in carbon nanotube-polystyrene composites, Applied Physics Letters Volume 76, Number 2, 2000, pp. 2868-2870

Dislocation density δ (Lin/nm), number of crystalline N (nm-2) and stacking fault probability α (nm) also calculated by blow equations [21]: δ=1/D^2 (2) N=1/D^3 (3) α= (2πD (θ))/ (45√ (3 tanθ)) (4) Table 1, summarized the structural parameters of obtained samples.
Stacking fault probability was increased after adding ZnO while the number of crystallizes decreased.
Images analysis showed small crystal grains observed with voids.
This change in the grain size and roughness after adding zinc oxide returns to the difference between particles between zinc and titanium, this is coming with the results of the researcher (Wisitsoraat, et al.,2009) [23].
The results of AFM showed the average distribution of grain size was (45.56 to 88.4) nm, and the roughness was (0.597 to 1.46) nm.

A number of technologies are used for ceramic coatings such as air plasma spraying (APS) and electron beam physical vapor deposition (EB-PVD) being the most common methods [3, 7, 8].
On the grain surfaces and for the larger grains within the grains a darker grey phase can be discerned (Fig. 1c).
Since decreasing yttria concentration decreases the number of oxygen vacancies, at which the phonons are scattered, thus leading to a higher thermal conductivity [22].