ANALYTICAL APPROACH TO DETERMINING OF PARAMETERS WHICH CHARACTERIZE SURFACE LAYER QUALITY OF THE PARTS HARDENED BY A TRAVELING DIAMOND SPHERE

Abstract The present work is dedicated to analysis of a plane boundary problem of a sphere movement along an elastic semi-plane. Moreover it is supposed that in the area of contact between the sphere and the semi-plane there will be sectors with multidirectional frictional load as well as a sector with adhesive bonds. By means of the received solution of the boundary problem we've evaluated the area of plastic deformation below the sphere based on the condition of equality of load and plasticity invariable (yield point ( y σ )). Plastic deformation height was considered to be the maximum height of plastic deformations penetration under the traveling sphere. Comparison of experimental and estimated data demonstrated accuracy acceptable for use of the elaborated method in real production. 1. Introduction Production process of a part surface hardening by its deformation by means of a traveling diamond sphere is distinguished from other surface plastic deformation methods due to resulting stable quality indices of the processed surface. Basic parameters characterizing the surface layer quality of the parts inclusive of those hardened by a diamond sphere are as follows: surface roughness, residual strain and cold deformation, i.e. distribution of microhardness across the surface layer after its hardening. The methods used nowadays for control of residual strain and distribution of microhardness ( H h ) throughout a part surface layer height result in destruction of the explored surface which is not acceptable in some cases, in particular during evaluation of large and case parts. That's why development of nondestructive methods for quantitative estimation of the surface layer parameters is a technological problem of current concern. For the parts being operated under the conditions of friction or repeated loads the height of mechanical hardening ( H h ) to a large extent is indicative of performance characteristics of the parts [1]. In this respect there was developed a method for analytical determination of the height of a plastically deformed layer of a surface subjected to hardening by means of a diamond sphere. Methodology Experimental determination of a mechanical hardening profile was performed with use of angle laps at the samples preliminary processed by a diamond sphere. Microhardness was measured on the basis of a reproduced impress formed by indentation of a Vickers diamond point with the force of 2 N in accordance with the standard GOST 9450-76 "Measurement of microhardness by diamond instruments". For measurement of the impress diagonal size the microhardness tester PMT-3 made by OJSC LOMO (Saint-Petersburg), Russia, was used. For determination of the height of the part plastically deformed surface layer the measurements were made approximately at the interval of 10 μm. The hardened surface layer height was determined as a distance measured along normal to the surface starting from the surface and ending at the place at which geometric dimensions of the Vickers point impress are no longer changed. The rings with the outer diameter of 62 mm and the width of 12 mm made of stainless steel 12Х18Н9Т (the national standard GOST 5632-72 "Superalloyed steels and corrosion-resistant, heat-resistant and heatproof alloys. Makes") were taken as samples. S.R. Abulkhanov et al. / International Journal of Engineering and Technology (IJET

A New Nanoporous Material Based on Amorphous Silicon Dioxide

Processes for making nanoporous SiO2 layers on Si via the irradiation of thermally oxidized silicon wafers with fast ions followed by chemical treatment in a solution or vapor of hydrofluoric acid are presented. It is shown that the density, shape, diameter, and length to diameter ratio of channels etched in silicon dioxide can be controlled by varying the regimes of fast ion irradiation or chemical treatment of SiO2/Si structures. Track parameters calculated using the thermal spike model are compared with the chemical etching data

Investigation of the microstructure of the fine-grained YPO4_4:Gd ceramics with xenotime structure after Xe irradiation

The paper reports on the preparation of xenotime-structured ceramics by the Spark Plasma Sintering (SPS) method. Phosphates Y$_{0.95}$Gd$_{0.05}$PO$_4$ (YPO$_4$:Gd) were obtained by the sol-gel method. The synthesized nanopowders are collected in large agglomerates 10-50 mkm in size. Ceramics has a fine-grained microstructure and a high relative density (98.67%). The total time of the SPS process was approximately 18 min. High-density sintered ceramics YPO$_4$:Gd with a xenotime structure were irradiated with Xe$^{+26}$ ions (E = 167 MeV) to fluences of $1\times10^{12}$-$3\times 10^{13}$ cm$^{-2}$. Complete amorphization at maximum fluence was not achieved. As the fluence increases, an insignificant increase in the depth of the amorphous layer is observed. According to the results of grazing incidence XRD (GIXRD), with an increase in fluence from $1\times10^{12}$-$3\times 10^{13}$ cm$^{-2}$, an increase in the volume fraction of the amorphous structure from 20 to 70% is observed. The intensity of XRD peak 200 YPO$_4$:Gd after recovery annealing (700$^\circ$C, 18 h) reached a value of ~80% of the initial intensity I0.Comment: 16 pages, 10 figure

Depth profiles of aggregate centers and nanodefects in LiF crystals irradiated with 34 MeV 84Kr, 56 MeV 40Ar and 12 MeV 12C ions

I. Manika, J. Maniks and R. Zabels acknowledge the national project IMIS2. A. Dauletbekova, A. Akilbekov, M. Zdorovets and A. Seitbayev acknowledge the GF AP05134257of Ministry of Education and Science the Republic of Kazakhstan.Depth profiles of nanohardness and photoluminescence of F2 and F3 + centers in LiF crystals irradiated with 12 MeV 12C, 56 MeV 40Ar and 34 MeV 84Kr ions at fluences 1010–1015 ions/cm2 have been studied using laser scanning confocal microscopy, dislocation etching and nanoindentation techniques. The room temperature irradiation experiments were performed at DC-60 cyclotron (Astana, Kazakhstan). It was found that the luminescence intensity profiles of aggregate color centers at low ion fluences correlate with electronic stopping profiles. The maximum intensity of aggregate center luminescence is observed at fluence around 1013 ions/cm2 and rapidly decreases with further increase of fluence. At the highest ion fluences, the luminescence signal is registered in the end-of-range area only. The depth profiles of nanohardness and chemical etching have shown remarkable ion-induced formation of dislocations and increase of hardness which in the major part of the ion range correlate with the depth profile of electronic energy loss. An exception is the end-of-range region where strong contribution of nuclear energy loss to hardening at high fluences is observed.IMIS2; Ministry of Education and Science the Republic of Kazakhstan GF AP05134257; Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART

IC100 cyclotron based facility for production of nuclear filters as well as for scientific and applied research

The complex based on the cyclotron IC100 of the Laboratory of Nuclear Reactions (JINR, Dubna, Russia) provides industrial fabrication of nuclear filters. During modernization the cyclotron was equipped with superconducting ECR-ion source and axial injection system. The specialized beam channel with two coordinates scanning system and equipment for irradiation of polymer films has been installed in the implantation part of the complex. High intensity heavy ion beams of Ne, Ar, Fe, Kr, Xe, I, W have been accelerated to 1 MeV/nucleon energy. The investigation of irradiated crystals features, irradiation of different polymer films have been provided. Also few thousands square meters of track films with holes in the wide range of densities have been produced. The cyclotron based complex is capable to solve different kinds of scientific and applied problems as well.На циклотронному комплексі ИЦ100 Лабораторії ядерних реакцій ОІЯД (м. Дубна, Россія) реалізовано промислове виготовлення ядерних фільтрів. У результаті проведення повної модернізації циклотрон був оснащений надпровідним ЕЦР-джерелом і системою зовнішньої аксіальної інжекції пучка. Інплантаційний комплекс був обладнаний спеціалізованим каналом транспортування з системою сканування пучка і установкою для опромінення полімерних плівок. Були отримані інтенсивні пучки важких іонів Ne, Ar, Fe,Kr, Xe, I, W з енергією біля 1 МеВ/нуклон. Був проведений ряд наукових досліджень по вивченню властивостей опромінених кристалів, проведене опромінення різних полімерних плівок, виготовлено кілька тисяч квадратних метрів трекових мембран у широкому діапазоні змін щільності отворів. Циклотронний комплекс здатний також вирішувати і інші науково-прикладні завдання.На циклотронном комплексе ИЦ100 Лаборатории ядерных реакций ОИЯИ (г. Дубна, Россия) реализовано промышленное изготовление ядерных фильтров. В результате проведения полной модернизации циклотрон был оснащен сверхпроводящим ЭЦР-источником и системой внешней аксиальной инжекции пучка. Имплантационный комплекс был оборудован специализированным каналом транспортировки с системой сканирования пучка и установкой для облучения полимерных пленок. Были получены интенсивные пучки тяжелых ионов Ne, Ar, Fe,Kr, Xe, I, W с энергией около 1 МэВ/нуклон. Был проведен ряд научных исследований по изучению свойств облученных кристаллов, проведено облучение различных полимерных пленок, изготовлено несколько тысяч квадратных метров трековых мембран в широком диапазоне изменения плотности отверстий. Циклотронный комплекс способен также решать и другие научно-прикладные задачи

Raman Study of CVD Graphene Irradiated by Swift Heavy Ions

CVD-graphene on silicon was irradiated by accelerated heavy ions (Xe, 160 MeV, fluence of 1011 cm-2) and characterized by Raman spectroscopy. The defectiveness of pristine graphene was found to be dominated by grain boundaries while after irradiation it was determined by both grain boundaries and vacancies. Respectively, average inter-defect distance decreased from ~ 24 to ~ 13 nm. Calculations showed that the ion irradiation resulted in a decrease in charge carrier mobility from ~ 4.0 × 103 to ~ 1.3·103 cm2/V s. The results of the present study can be used to control graphene structure, especially vacancies concentration, and charge carrier mobility

СПЕКТРЫ DLTS КРЕМНИЕВЫХ ДИОДОВ С p+—n–ПЕРЕХОДОМ, ОБЛУЧЕННЫХ ВЫСОКОЭНЕРГЕТИЧЕСКИМИ ИОНАМИ КРИПТОНА

p+-n-Diodes have been studied. The diodes were manufactured on wafers (thickness 460 μm, (111) plane) of uniformly phosphorus doped float–zone–grown single–crystal silicon. The resistivity of silicon was 90 Ohm · cm and the phosphorus concentration was 5 · 1013 cm–3. The diodes were irradiated with 250 MeV krypton ions. The irradiation fluence was 108 cm–2. Deep–level transient spectroscopy (DLTS) was used to examine the defects induced by high energy krypton ion implantation. The DLTS spectra were recorded at a frequency of 1 MHz in the 78—290 K temperature range. The capacity–voltage characteristics have been measured at a reverse bias voltage from 0 to –19 V at a frequency of 1 MHz. We show that the main irradiation–induced defects are A–centers and divacancies. The behavior of DLTS spectra in the 150—260 K temperature range depends essentially on the emission voltage Ue. The variation of Ue allows us to separate the contributions of different defects into the DLTS spectrum in the 150—260 K temperature range. We show that, in addition to A–centers and divacancies, irradiation produces multivacancy complexes with the energy level Et = Ec – (0.5 ± 0.02) eV and an electron capture cross section of ~4 · 10–13 cm2.Исследованы p+—n-диоды. Диоды изготовлены на пластинах однородно легированного фосфором монокристаллического кремния (толщина 460 мкм, плоскость (111)), выращенного методом бестигельной зонной плавки. Удельное сопротивление кремния — 90 Ом × см, концентрация фосфора — 5 × 1013 см−3. Диоды подвергнуты облучению ионами криптона с энергией 250 МэВ. Флюенс облучения — 108 см−2. Радиационные дефекты, вводимые высокоэнергетической имплантацией ионов криптона, исследованы с помощью нестационарной спектроскопии глубоких уровней (DLTS — Deep−level transient spectroscopy). Спектры DLTS регистрировали на частоте 1 МГц в интервале температур 78—290 К. Вольт-фарадные характеристики измерены при напряжении обратного смещения от 0 до – 19 В на частоте 1 МГц. Показано, что основными радиационными дефектами являются А−центры и дивакансии. Установлено, что вид спектров DLTS в интервале температур 150—260 K существенно зависит от напряжения эмиссии Ue. Варьирование Ue в ходе эксперимента позволило разделить вклады от различных дефектов в спектр DLTS в интервале температур 150—260 К. Показано, что, помимо А−центров и дивакансий, при облучении формируются многовакансионные комплексы с энергетическим уровнем Et = Ec -(0,50 ± 0,02) эВ и сечением захвата электронов ~ 4 × 10−13 см2

Information support of international cooperation

The article is devoted to the information support of the international cooperation in the education sphere by means of the Information and analytical system “Education In Russia For Foreigners” and the Information systems for the international partnership in education between Russia and the USA, Spain, France, Germany and China