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It should be noted that threaded gears used in metrological instruments and a number of other critical structures are involved in the measurement process or in movements that require high accuracy only by touching one side of the profile.
Reducing it allows you to reduce the number of passes, maintaining and even somewhat “softening” the grinding conditions.
A gear made of steel 12ХН3А was chosen as the object of study: number of teeth z = 32, tooth length l = 45 mm, module m = 5 mm (Fig. 1).
According to the results obtained, the improved technology for grinding teeth with copying provides the necessary accuracy, despite the reduction in the number of working passes, while reducing the main technological time by ≈20 %.
Analysis of grinding mechanics and improved grinding force model based on randomized grain geometric characteristics.

Wrought iron was essential because it had high ductility and strength in the longitudinal direction, due to the ductile iron grains; transverse cracks had a fibrous (silky) appearance (now referred to as dimpled) due to formation of voids at the slag [5,8-10].
optimum spacing and number of rows of rivets [1,11].
The brittleness had been induced by WI workers inadvertently over heating to liquefy low melting impurities at the grain boundaries.

There will always be a carbon flux through the chromia layer especially at weaker points such as the middle of larger surface grains [14].
The numbers show EDS-analysis points with following phases: (1):Ferrite, (2):M7C3, (3):M3C-carbide, (4):Oxide with carbon, (5):Fe-rich particles, (6):Coke; carbon and oxides.
These two processes work in collaboration; the carbides dissolve since there is a decreasing Cr-gradient towards the Crcontaining oxide and the process is promoted by the fine structured austenitic layer with graphite flakes, which provide fast Cr-diffusion paths by phase/grain boundary diffusion.

This is due to the grain coarsening leading to a decreasing sampling statistic at high temperature.
Then, diffraction rings belonging to martensite appear, and the diffraction rings of austenite become more and more close due to a plastic deformation and related increasing number of crystallites.
However, X-ray diffraction techniques give average information of thousands (millions) of “grains” which in general are randomly oriented, and therefore the average information contained in the measured area might be predominantly hydrostatic.

It has also been noted that the S-Phase layer thickness in the duplex stainless steel was thinner in the grains which were formerly ferrite than in the grains of austenite due to the different solubility and diffusability of nitrogen [4] in both phases.
Williamson et al. was demonstrated that the S-Phase was created in a number of commercial nickel alloys such as Hastelloy X, Nickel 625, Inconel 600, Nichrome and Permalloy by N-ion beam processing.

This ability is unique to the HSPT process, and is not capable from vacuum sintering due to the coarse lamellar grains.
Acknowledgements The authors gratefully acknowledge the funding provided by the US Department of Energy through the Advanced Manufacturing Office of Energy Efficiency and Renewable Energy, award number DE-EE0005761.
Wang, “Hydrogen Sintering of Titanium to Produce High Density Fine Grain Titanium Alloys,” Adv.

The UK and USA experiences resulted in a number of clinical and retrieval studies (Table 1) that may or may not be relevant to today's modular cup designs incorporating alumina liners (D' Antonio et al., 2002).
There was grain erosion over about 25% of such worn ball surfaces and these corresponded to areas damaged by the cup-rim.
Table 2: Materials, design and surgical issues implicated in COC THR failures # Parameter Concerns 1 Inferior alumina grades low density, large grains 2 Inferior design concepts range of motion, dome holes 3 Cup placement too vertical rim wear of cup on ball 4 Poor anatomical positioning of cup neck-socket impingement 5 Cup loosening, rotation & migration rim wear; neck-socket wear 6 Poor bone inferior fixation 7 High patient activity frequent extensive ROM, high stresses The studies of "severe" wear in Mittelmeier THR seldom offered insight into clearly identifiable "suspect" ceramic parameters or patient-related risks in individual cases (Table 1).

In recent years, a number of materials such as tungsten oxides [3], molybdenum trioxide [4, 5], titanium dioxide [6], metal (Ag) [7] and metal halide (AgCl) [8] have been extremely interested to produce photochromic materials.
The largest crystallite size of h-MoO3 was observed at pH 1.0 due to the fact that low pH value of the solution promotes the transformation of intermediate (NH4)2Mo4O13 phase to h–MoO3 structure and its grain growth.
The formation of rod–like h–MoO3 is as a result of the excess H+ ions from concentrate HNO3 in the reaction resulting in a phenomenon of one direction grain growth to generate the according well–faceted rod MoO3 [20].

. % AlN with high thermal stability (450-500oC) and high-temperature strength superior to typical sintered aluminum alloys and composites Al-AlN with large grains [22, 23].
However, the implementation of aluminum matrix composites reinforced with AlN particles in production has been hampered by a number of unsolved technological and economic problems.
Qian, SAP-like ultrafine-grained Al composites dispersion strengthened with nanometric AlN, Mater.

Accordingly control parameters currently are grouped into four categories about the: a) Particles: size, shape, porosity, density and chemical composition; b) Thermite powder: size, roundness, specific surface area, bulk density; c) Thermite: specific surface area, apparent density, pore volume in and of the particles, average pore size, pore shape, pore size distribution, reaction rate, reaction temperature, explosive limit, amount of heat, amount of metal and amount of corundum; d) Thermitic metal: casting temperature, chemical composition, porosity, expansion coefficient, inclusion rate, metallographic structure, grain size, residual oxygen and hydrogen, mechanical properties (Rm, KCV and HV).
For this goal proposes currently using AW controls parameters that highlight the iron oxide percent as function of the grains size.
QUARK 1 Diagram can limit the number of attempts needed to determine the quantities of the TK [metallic oxides, atomized Al powder, graphite powder, ferroalloys (HCFeMn78, HCFeCr70, FeTi70, and FeNi45), reaction inhibitor (OL37) and flux (fluorite)], within 3.