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Coatings produced by FS are also known to be free of pores and solidification cracks and present a fine grained structure caused by dynamic recrystallization during the process [2, 8].
This work was partially funded by FAPEMIG (grant number PPM-00662-18), CNPq (grant number 409139/2016-5) and the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001.

As expected, such kind of equations requires complex and expensive laboratory trials to obtain the flow stress as a function of grain dimension, dislocation density, etc.
Equivalent stresses (s) and deformations (e) were derived from t and γ as: where M is the torque in Nm, N the number of revolutions.
· In that way each complex equation can be put in the linear form: (7) The same consideration can be made for equations characterised by a more elevated number of variables.

Introduction The process of production of high-energy permanent magnets (HEPM) having rare-earth metals, using the method of powder metallurgy, includes the stage of production of powders of appropriate alloys having desired size of grains and physical-mechanical parameters.
On a number of occasions the reaction proceeds rather actively even at a room temperature.
In a number of cases, metallographic samples of the alloy were used as a preform to carry out the metallurgical study of modification of the sample surface during hydrogenation.

Especially in the recent century, to meet rapid grain needs with increasing population, intensive farming, chemical fertilizers overusing and machine tilling to agriculture changed fertility and productivity of arable lands, and also biogeochemical cycles of carbon and nitrogen in agro-ecosystems, which led to more greenhouse gas emission s including CO2, CH4 and N2O from rural ecosystems [4], and then affected global climate.
Main soil types in Gaoyi County a) Code Soil type Soil group Area (hm2) Area percentage % Number of samples 1 Sandyloam limestone cinnamon soil Cinnamon soil 140.28 0.67 2 2 Lightloam cinnamon soil 3522.37 16.8 26 3 Thick-stone lightloam cinnamon soil 67.84 0.32 1 8 Low-stone lightloam cinnamon soil 54.74 0.26 2 10 Sandyloam meadow cinnamon soil 184.76 0.88 1 12 Lightloam meadow cinnamon soil 15226.9 72.54 58 15 Deep-clay lightloam meadow cinnamon soil 923.81 4.39 8 a) Soil codes instead of soil type names will be used in the contents below.
In this region, these driving factors included the increasing numbers of harvest machine, farming machine and irrigation machine etc.

The value L, m was determined by the height of the grinding chamber and the number of passes of the material through it.
The average size of the crushed grains was determined from the data obtained from "SK LAZER MICRON SIZER".
The material was put through the grinding chamber a certain number of times to set the grinding path L equal to 1, 2 and 3 m.

It allowed for consideration of the fine morphological features of the scale and the scale/metal interface while, at the same time, reducing the number of elements under consideration (Fig.1).
Rolling of the specimens at higher speeds and aspect ratios resulted in rapid removal of material from the stock surface due to abrasion and adhesion, a churned up a subsurface layer with fine grains and mechanically entrained oxides.
The numerical results indicated a tendency for an abrupt increase in the number of through-thickness cracks and decrease of crack spacing at some level of the tensile strain.

In case of a deformation occurring in the α+β-region, the softening processes are defined not only by the strength of the α- and β-phases, but also by their number, as well as the potential of each phase for plastic deformation, the ease of sliding transmission at the interphase and intergrain boundaries, the aspects of the development of dynamic hardening and softening processes in two-phase structures.
The high strength of these alloys may be due to both solution hardening and microstructural hardening, since alloys with an approximately equal number of phases have a smaller grain size [1].

The pit size and number of non coated Co-Cr alloy is severely attacked along with grain boundaries Centrifugal casting� High frequency induction casting Vacuum pressure casting Non (TiN) A alloy� B alloy C alloy A alloy B alloy C alloy A alloy B alloy C alloy I corr (A/�)� 1.88X10-7 (7.49X10-6) 1.42X10-6 (1.19X10-6)� 5.13X10-7 (8.14X10-6)� 1.65X10-7 (1.50X10-6)� 6.62X10-7 (5.93X10-7)� 1.39X10-7 (7.81X10-6)� 1.81X10-7 (6.78X10-6)� 8.87X10-7 (7.14X10-8)� 1.20X10-7 (6.80X10-6)� I 300m V (A/�)� 1.06X10-6 (9.00X10-5)� 1.65X10-1 (8.64X10-5) 1.80X10-4 (1.20X10-4) 3.35X10-4 (2.24X10-6) 4.26XX10-2 (7.22X10-5) 1.09X10-4 (2.90X10-5) 4.19X10-4 (6.00X10-5) 2.58X10-2 (6.89X10-5) 1.43X10-4 (5.00X10-5) E corr (mV)� -461 (-422) -373 (-330) -401 (-394) -381 (-289) -287 (-355) -475 (-261) -444 (-245) -268 (-260) - 436 (-309) E pit (mV)� +720 (+830)� +130 (+150) +740 (+900)
Summary The number of casting defects of samples decreased in the order of centrifugal casting , high frequency induction casting, and vacuum pressure casting method due to increment of casting density, especially, pore defects were found at part of minor connector because of thin casting thickness in the case of centrifugal casting method.

HVOF Cr3C2-NiCr coating also showed excellent erosion-corrosion behaviour, high compactness, fine grain size structure and homogeneous distribution[6].
The Addition of CrC(20NiCr) as reinforced material in metal matrix was employed with high velocity oxigen fuel (HVOF) systems with the constant parameter in order to increase the coating capability on thermal shock resistance without decrease significantly their original characteristic on hardness number.
MMC with 140 mesh of NiCr particle size is the most heavily unmelted particles and spread, while MMC with 270 mesh of NiCr particles size, the number of splats which is dominated by Cr and Ni element than unmelted particles.

The TCP sample displays all main peaks that is in agreement with one of XRD pattern reference for β-TCP according to ICDD PDF Number 00-009-0169.
On the other hand, when chitosan was included in the precipitation process (TCP-K), the secondary phase of calcium pyrophosphate (CPP) appeared at 2θ angle of 32,102, according to XRD pattern reference for CCP with ICDD PDF Number 00-020-0024.
Pure β-TCP powder has a typical morphology of nanoscale single particles but mostly agglomerated grains [10, 12].