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By considering the contents of Cr and Mo, the pitting resistance equivalent number (PREN) of each weld metal was calculated.
For specimens welded using CS fillers (Fig.5), the continuity of the microstructure from CSBM to weld metal was observed, but with the large grain sizes in the heat affected zone (HAZ) on the CSBM side (Fig.5(a)).

Heat generating from friction stir and cooling cause intense plastic deformation (material flow) through the stirring action, which create dynamically recrystallized fine grains, break up the large particles and produce defect free homogenous microstructure [9, 10].
Furthermore, two-pass FSP, with100% overlapping, results in an increase in the number of small-sized particles [17,18].
Saito, “Mechanical Property Improvements in Aluminum Alloy through Grain Refinement using Friction Stir Process,” Mater.

Upon development the microstructural, physical, and electrochemical behaviours will be evaluated. 2 Materials and Methods 2.1 Materials 2.1.1 Zinc Zinc is an important element in the periodic table with an atomic number of 30.
Working together, material scientists, electrochemists, and corrosion specialists may provide a thorough grasp of the behaviour of the coatings and their implications for a variety of applications. 4.2 Conclusions Coating thickness played a pivotal role in enhancing properties across various fronts: the presence of additives not only increased thickness but also bolstered grain growth and boundaries, subsequently improving overall properties and reducing cathodic current densities.
Moreover, the coated samples exhibited marked increases in hardness, with Zn-6CaO-6MnO2 displaying the highest hardness, owing to microstructural alterations influenced by factors like residual stress, porosity, phase composition, binder content, and grain size.

Air-Cushion belt conveyor as well as traditional conveyor, could be widely used to transport all kinds of bulk materials internally and between each department of industry, such as coal, metallurgy, chemical, electric, building, grain, port and coal mine.
The length of air-cushion is L=40mm, the number of the air-hole rows is n=7, the row space position angles are θ=8 ,16 ,24 .
Li: Journal of Zhengzhou Grain College.

To define the heat flux to the grinding wheel, a partition ratio Rws of “workpiece – grinding wheel”, which is independent of the heat to the chips and coolant, is introduced in Eq. 4 based on Hahn’s model for a grain sliding on a workpiece with the grinding wheel speed vs [18]
The value r0 describes the radius of an average CBN grain and λk the thermal conductivity of CBN abrasives.
Fig. 3, Temperature along the tool path after 0.1 s with heat flux qt = 0.17 kW/mm² A dimensionless number of x/lc was introduced in Fig. 3 to illustrate the different positions of maximum temperatures, where lc is the contact length and x is the position along the line of the moving heat source.

Therefore, it can be said that Al present in the secondary phases (areas between large grains) as NbAl3, Cr2Al and Mo3Al was used for the Al2O3 formation.
The formation of the initial Al2O3 layer may be mainly due to grain boundary diffusion of Al, though Al of AlNbCr phase (major phase) was also used for this.
This may be related to the increase in the number of small cracks in it.

Four effects (two exothermic and two endothermic), numbered I to IV, are evident.
(c, d and e adapted from [21]) The strength model In polycrystalline materials several hardening mechanisms operate, and the yield strength should generally be given by [25]: σy = ∆σGB + M·τtot (1) where ∆σGB is the grain boundary strengthening, M is an orientation factor (often termed the Taylor factor), and τtot is the critical resolved shear stress (CRSS) of the grains which is determined by several strengthening mechanisms, most notably intrinsic hardening, precipitate hardening (including co-cluster hardening) and solution hardening.

In Fig. 2(b), a close-up view of region I shows relatively coarse grains in the base metal.
In Fig. 2(c), a close-up view of region II shows finer grains with dispersed pure aluminum layers (marked by small arrows) in the stir zone.
For the limited number of specimens available, we could not determine more precisely the applied load range for the transition of one cracking mode to the other.

The average grain sizes of the samples were calculated using the Scherrer equation according to the full width at half maximum (FWHM) of the peak at 2θ =12.7°.
The order of grain size is: OL (1.5 nm) > 0.1Ag/OL (0.9 nm) > 0.2Ag/OL (0.7 nm) > 0.5Ag/OL (0.6 nm) > 0.3Ag/OL (0.5 nm).
Fig. 7 Catalytic activity of OL and xAg/OL for CO Table 2 The T50 and T90 for CO oxidation of OL and xAg/OL Sample CO/T50 (°C) CO/T90 (°C) OL 125 169 0.1Ag/OL 120 151 0.2Ag/OL 110 142 0.3Ag/OL 105 135 0.5Ag/OL 108 138 The reaction rate rcat can be better reflect the catalytic activity [10], where rcat is the number of moles of CO converted per gram of catalyst per second.

The transfer of these cracks from one layer to the next one is delayed to a higher number of cycles [6-8, 10].
Hockey, Crack-Interface Grain Bridging as a Fracture Resistance Mechanism in Ceramics: I, Experimental Study on Alumina, Journal of the American Ceramic Society Vol. 70 No. 4 (1987) 279-289
Lawn, Crack-Interface Grain Bridging as a Fracture Resistance Mechanism in Ceramics: II, Theoretical Fracture Mechanics Model, Journal of the American Ceramic Society Vol. 70 No. 4 (1987) 289-294