Effect of the technological conditions of frictional treatment on the structure, phase composition and hardening of metastable austenitic steel

The process parameters of the frictional treatment (indenter material, medium, load) of the 12Kh18N10T chromium-nickel austenitic steel have been optimized for the criteria of strain hardening and the quality of the surface being treated. The paper studies effect of the multiplicity of the frictional action of a synthetic diamond indenter at room temperature in an argon medium and the loading temperature ranging between -196°C and +250°C on the hardening, phase composition and fine structure of the surface layer of the steel. It has been found that the completeness of the strain-induced γ→α′ martensitic transformation in the surface layer of the steel is strongly dependent on the multiplicity and temperature of loading and that the level of hardening rises with the multiplicity of action, but shows little dependence on the temperature of frictional treatment. © 2016 Author(s).Russian Foundation for Basic Research, RFBR: 15-08-0794701201354598Ural Branch, Russian Academy of Sciences, UB RAS: 15-9-12-45The work was done in the framework of the Complex Program of UB RAS (project No. 15-9-12-45) and the government assignment for IES UB RAS, theme No. 01201354598 supported by RFBR, project No. 15-08-07947

Increasing the micromechanical and tribological characteristics of an austenitic steel by surface deformation processing

Frictional treatment (FT) with a sliding indenter forms highly dispersed (nano- and submicrocrystalline) austenitic structures with a hardness of 720 HV 0.025 in the surface layer of the 03Cr16Ni14Mo3Ti austenitic strain-resistant steel. According to the data on microindentation, FT increases the strength and of the surface layer of the austenitic steel and its resistance to elastic and plastic deformation. A high effectiveness of FT in the improvement of the tribological properties of the steel is demonstrated; namely, wear resistance increases 4 times under conditions of boundary friction as compared to the undeformed state. This is due to reduced plastic edging on the nanostructured surface. © 2018 Author(s)

Improving the scratch test properties of plasma-nitrided stainless austenitic steel by preliminary nanostructuring frictional treatment

The paper studies the effect of nanostructuring deformation surface processing - frictional treatment performed prior to the operation of nitriding in electron beam plasma - on the quality of the surface and tribological properties of the nitrided layer of the AISI 321 chromium-nickel austenitic steel. For the surface layers nitrided in the undeformed coarse-crystalline and nanostructured states, considerable differences in the critical loads and the fracture patterns under scratch testing are observed, despite practically the same microhardness of the nitrided surfaces under study. It is demonstrated that preliminary frictional treatment increases the rupture strength of the nitrided layer under scratch testing and stabilizes the tribological properties of the surface on the macroscopic scale. © 2018 Author(s)

Eddy-current testing of fatigue degradation in additionally heat-treated gas powder laser clad NiCrBSi coating under contact fatigue loading

The paper studies the applicability of eddy-current technique to testing fatigue degradation in Ni-18.2Cr-3.3B-4.2Si coating, produced by gas powder laser cladding and subjected to additional high-temperature annealing at 1025 °C, under contact loading. It is demonstrated that eddy-current testing of fatigue degradation in Ni-18.2Cr-3.3B-4.2Si coating under contact loading after high-temperature annealing has certain limitations caused by the high brittleness of this coating. In this case, it is possible to test only a sharp increase in the sizes of contact damages, which occurs at 8×10 5 cycles under these loading conditions and results from the formation of a great number of peripheral ring cracks in the fracture zone; the eddy-current readings α decrease due to the increasing electrical resistivity of the coating. Testing can be performed by eddy-current measurements at high excitation frequencies of an eddy-current transducer (f=72-120 kHz), when the effect of the ferromagnetic steel base on the eddy-current readings α is minimum. © 2018 Author(s)

Effect of preliminary nanostructuring frictional treatment on the efficiency of nitriding of metastable austenitic steel in electron beam plasma

The paper studies the effect of the temperature of nitriding in electron beam plasma, ranging between 250 and 500 °, on the nitrogen concentration, phase composition and microhardness of the surface of the AISI 321 chromium-nickel austenitic steel in two initial states - quenched undeformed and after nanostructuring frictional treatment. The lowest nitriding temperature (350 °C) for the efficient hardening of the steel has been established. The application of frictional pretreatment with a sliding synthetic diamond indenter in an argon environment is shown to be highly efficient for increasing the depth of the layer nitrided at this temperature. The contribution of the formed S-phase (nitrogen-oversaturated austenite γN) to the intensive hardening of the steel nitrided at low temperatures (300 to 400 °) is noted. © 2017 Author(s).01201354598Russian Foundation for Basic Research, RFBR: 15-08-07947Ural Branch, Russian Academy of Sciences, UB RAS: 15-9-12-45, 01201463331The work was done in the framework of the Complex Program of UB RAS (project No. 15-9-12-45), within the state order on the subject “Structure” (No. 01201463331), the government assignment for IES UB RAS (theme No. 01201354598) and supported by RFBR, project No. 15-08-07947

Eddy-current testing of fatigue degradation upon contact fatigue loading of gas powder laser clad NiCrBSi-Cr 3 C 2 composite coating

The possibilities of the eddy-current method for testing the fatigue degradation under contact loading of gas powder laser clad NiCrBSi-Cr 3 C 2 composite coating with 15 wt.% of Cr 3 C 2 additive have been investigated. It is shown that the eddy-current testing of the fatigue degradation under contact loading of the NiCrBSi-15%Cr 3 C 2 composite coating can be performed at high excitation frequencies 72-120 kHz of the eddy-current transducer. At that, the dependences of the eddy-current instrument readings on the number of loading cycles have both downward and upward branches, with the boundary between the branches being 3×10 5 cycles in the given loading conditions. This is caused, on the one hand, by cracking, and, on the other hand, by cohesive spalling and compaction of the composite coating, which affect oppositely the material resistivity and, correspondingly, the eddy-current instrument readings. The downward branch can be used to monitor the processes of crack formation and growth, the upward branch - to monitor the degree of cohesive spalling, while taking into account in the testing methodology an ambiguous character of the dependences of the eddy-current instrument readings on the number of loading cycles. © 2017 Author(s)

Cognitive-perceptive features and communicative orientation of nominative meaning of the verbs of olfactory semantics in French

The article deals with systemic-structural possibilities of the verbal nomination of the French language in the field of description of a smell as a result of the olfactory perceptio

КОМПЛЕКСНАЯ АГРОЭКОЛОГИЧЕСКАЯ ОЦЕНКА ПРИМЕНЕНИЯ НЕТРАДИЦИОННЫХ УДОБРЕНИЙ

The article shows the results on soil recycling of municipal waste. The authors declare that application of unique fertilizers dosed economically efficient does not influence much the qualities of grey forest soil plough-layer. Single application of wastewater sludge dosed as 12t/ha increases humus concentration, cation exchange capacity and environmental pH becomes weakly alkaline. The paper finds out that efficient application of wastewater sludge doesn’t make effect on element burden and doesn’t break ecological balance. The authors conduct research on soil recycling of municipal waste with lime, which causes alkalinization of the soil in order to reduce migration mobility of heavy metals, which restrict their application. The research has shown that all parameters of total heavy metals were lower than admissible concentration unit in the years of fertilizing and in the following years. Soil pollution was minimal according to all criteria. The authors estimated bioenergetics efficiency of single application of wastewater sludge dosed as 12 t/ha when growing potato. Single application of wastewater sludge dosed as 12 t/ha demonstrated that wastewater sludge is high energy fertilizer. Stacking energy in extra yield at single application of wastewater sludge increased energy coefficient for the 3d year. This contributes to soil recycling of wastewater sludge as a fertilizer in case of biogeo-chemical monitoring of heavy metals concentration in the soil for growing environmentally sound production.Приведены результаты исследования почвенной утилизации бытовых отходов. Установлено, что применение нетрадиционных удобрений в экологически обоснованных дозах не оказывает значительного пролонгированного действия на свойства пахотного горизонта серых лесных почв. При одноразовом применении осадков сточных вод (ОСВ) в дозе 12 т/га повышается содержание гумуса, увеличивается ёмкость катионного обмена, pH среды смещается к слабощелочной. Показано, что рациональное использование ОСВ не оказывает значительного влияния на элементную нагрузку и не нарушает экологического равновесия. С целью снижения миграционной подвижности тяжелых металлов, ограничивающих их применение, проведены исследования почвенной утилизации ОСВ совместно с  известью, вызывающей подщелачивание почвы. Установлено, что все показатели валового содержания тяжелых металлов как в годы внесения удобрения, так и  в  последующие были ниже ПДК. Уровень загрязнения почвы по величине суммарного показателя концентрации по всем вариантам минимальный. Оценена биоэнергетическая эффективность и  определены расчётные коэффициенты энергетической эффективности при одноразовом применении ОСВ в дозе 12 т/га при выращивании картофеля. При однократном внесении ОСВ в дозе 12 т/га установлено, что они являются высокоэнергетическим перспективным удобрением. Энергия накопления в  прибавке урожая при одноразовом внесении ОСВ обеспечила наибольшее увеличение коэффициента энергетической эффективности на третий год последействия. Результаты исследований свидетельствуют о возможности почвенной утилизации ОСВ в качестве удобрений при условии организации биогеохимического мониторинга содержания тяжелых металлов в почве для выращивания экологически безопасной продукции

Вариабельность гематологических показателей у коров в зависимости от физиологического статуса

The object of the study was Holstein cows of the second-fourth milk secretion and first-calf cows of different production groups formed depending on the physiological status of the animals. The most pronounced hematological changes were observed in sexually mature cows during the first three months of milk secretion. After fawning, the number of erythrocytes, lymphocytes, and hemoglobin decreased. The concentration of bloodforming elements in the groups with a first-calf cow was significantly higher than in sexually mature cows. The level of erythrocytes and hemoglobin in first-calf cows reaches its maximum value at the beginning of milk secretion. Sexually mature cows after the first month of milk secretion were statistically significantly superior to first-calf cows at the beginning of milk secretion in terms of granulocyte content. Cows, in the first days of milk secretion, had the most fantastic range of variability in the scope of erythrocytes, leukocytes, and hemoglobin, which reflects the individual response of the body to significant changes in physiological status. At the same time, the first-calf cows at the beginning of milk secretion had the most stable level of these hematological indices. Dry cows, as a rule, occupied an intermediate position regarding the variability of the content of blood form elements. Thus, assessing the hematological profile of cows of different production groups helps specialists make targeted adjustments to rations and housing conditions, effectively manage genetic resources and obtain high profits.Объектом исследования являлись коровы голштинской породы второй-четвертой лактаций и первотелки разных производственных групп, сформированных в зависимости от физиологического статуса животных. Наиболее выраженные гематологические изменения наблюдались у половозрелых коров в первые три месяца лактации. После отела у животных отмечалось снижение количества эритроцитов, лимфоцитов, содержания гемоглобина. В группах с первотелками концентрация форменных элементов крови была достоверно больше по сравнению с половозрелыми коровами. При этом уровень эритроцитов и гемоглобина у первотелок достигает максимального значения в начале лактации. Половозрастные коровы после первого месяца лактации по содержанию гранулоцитов статистически значимо преобладали над первотелками в начале лактации. У коров в первые дни лактации наблюдался наибольший размах изменчивости содержания эритроцитов, лейкоцитов, гемоглобина, что отражает индивидуальную реакцию организма на значимые изменения физиологического статуса. При этом у первотелок в начале лактации уровень данных гематологических показателей был наиболее стабильным. Сухостойные коровы по вариабельности содержания форменных элементов крови, как правило, занимали промежуточное положение. Таким образом, оценка гематологического профиля коров разных производственных групп помогает специалистам производить направленную корректировку рационов и условий содержания, эффективно управлять генетическими ресурсами и получать высокие прибыли