Effect Of Electron Beam Treatment Research Articles

Effect of Electron Beam Treatment on the Structure, Properties and Fracture Behavior of High-Entropy Co – Cr – Fe – Mn – Ni Alloy

Effect of Electron Beam Treatment on the Structure, Properties and Fracture Behavior of High-Entropy Co – Cr – Fe – Mn – Ni Alloy

Control Over the Reactivity of Aggregates and Mineral Additives in Portland Cement Compositions by Electron Beam and Heat Treatment

The effect of electron-beam treatment (EBT) and heat treatment (HT) of silica-based aggregates and mineral additives in Portland cement mortars on the intensity of alkali-silica reactions (ASRs) with their participation, which are dangerous for concrete structures, is studied. It is established that heating to a temperature of 900°C and the EBT of sand free of alkali-reactive inclusions, leads to a significant increase in the reactivity of cement-sand mortar mixtures, which increases with an increase in the absorbed dose and a corresponding increase in the content of acid hydroxyl groups on the sand surface. In the case of sand containing reactive inclusions of chalcedony, EBT leads to an increase in reactivity, and HT, to a decrease. Treatment of microsilica and metakaolin mineral additives capable of ASR inhibition leads to an increase in their inhibitory effect. The results obtained are promising for modeling the expansion of concrete as a result of ASR and increasing their resistance to fracture in alkaline media.

Effect of electron-beam treatment on the structure and properties of (B + Cr) film deposited on a high-entropy alloy AlCrFeCoNi

The B + Cr film with a thickness of ∼ 1 µm was deposited by plasma-assisted RF sputtering on AlCrFeCoNi HEA of non-equiatomic composition prepared by WAAM. The subsequent treatment included electron beam irradiation of the surface with parameters as follows: energy density Es=(20–40) J/cm2, pulse duration 200 µs, frequency 0.3 s−1, number of pulses 3. It has been proved that microhardness increases by 2 times and wear resistance – by 5 times, whereas friction coefficient decreases by 1.3 times at an energy density Es = 20 J/cm2. High-speed crystallization of the surface layer leads to the formation of a cellular structure with cell sizes (150–200) nm. The increase in strength and tribological properties effected by electron beam treatment has been interpreted with the three factors in view: (1) the decreasing cell size, (2) formation of chromium and aluminum oxyborides, (3) formation of a HEA crystal lattice incorporating solid solution of boron.

Effect of electron beam treatment on the structure and properties of AlCoCrFeNi high-entropy alloy

In the last decade the attention of scientists in the field of physical material science has been drawn to the study of high entropy alloys. Using wire arc additive manufacturing (WAAM) technology the high-entropy alloy (HEA) AlCoCrFeNi of nonequiatomic composition has been produced (wt. %: 15.64 Al; 7.78 Co; 8.87 Cr; 22.31 Fe; 44.57 Ni). It is shown by methods of modern material science that the HEA is a polycrystalline material with a grain size 4–15 μm along whose grain boundaries the second-phase particles are detected. It is shown by the mapping methods that bulks of grains are enriched in aluminium and nickel while grain boundaries contain chromium and iron. Cobalt is quasi-uniformly distributed in crystal lattice of the manufactured HEA. The material ultimate strength in testing for compression depends on production mode and varies within the interval from 1300 to 1800 MPa. The HEA wear parameter amounts to 1.4∙10−4 mm3/N⋅m, friction coefficient — 0.65. In testings for tension the material failure occurred by the mechanism of intragrain cleavage. The formation of brittle cracks along boundaries and in grain boundary junctions i.e. in sites containing the inclusions of second phases is revealed. One of the reasons of HEA increased brittleness is the revealed nonuniform distribution of elements in alloy structure. The HEA’s irradiation by pulsed electron beam with energy density of 10–30 J/cm2 (pulse duration 200 μs, number of pulses 3) results in material homogenization. High-velocity crystallization of molten surface layer of HEA samples is accompanied by the formation of columnar structure having a submicro-nanocrystalline structure. The HEA irradiation results in the increase in hardness and plasticity of the material. The largest increase (1.6 times) in ultimate strength is obtained in the alloy after electron beam processing with energy density of 30 J/cm2. Electron beam processing leads to decrease in microhardness of alloy surface layer up to 90 μm thick. The research was supported by Russian Research Foundation grant (RSF) (project № 20-19-00452).

Synthesis of ZnS:Cu,Br radioluminescent phosphors using the electron-beam treatment and studying their characteristics

ZnS:Cu radioluminescent phosphors find their applications in medicine nondestructive testing, safety control and can be used as a part of the solid-state radioluminescent light sources (SRLS). This devices are very promising technology due to their independence longevity and safety compared to the gas-filled RLS. Because of the fact that tritium (the most popular radioisotope for RLS) has a very short range in substances, the improving the operating performances of radiophosphors is a crucial task for SRLS. In our study we used the electron-beam treatment to increase the brightness of radioluminescence of ZnS:Cu phosphors. It was found that bombardment of the phosphors initial charge with electrons of 900 kEv energy improves the brightness of radioluminescence by 15 – 20%. Double modifying of the initial charge and ready phosphor cause the 80% increase of brightness. The effect of electron-beam treatment on the phase content and the surface properties was studied at varying the content of activator (Cu) in the range of 0 – 0.6 % mass. As a result the model describing structure of the acid-base sites on the ZnS:Cu phosphor surface was suggested.

Study of the Effect of Electron Beam Treatment on the Properties of Triaminotrinitrobenzene

Study of the Effect of Electron Beam Treatment on the Properties of Triaminotrinitrobenzene

Study of the Effect of Electron Beam Treatment on the Properties of Triaminotrinitrobenzene

Study of the Effect of Electron Beam Treatment on the Properties of Triaminotrinitrobenzene

Effect of Electron-Beam Treatment on the Structure of Commercial-Purity Titanium Subjected to Fatigue Failure

The fracture surface, the phase composition and the state of the defect substructure of the titanium VT1-0 alloy subjected to preliminary irradiation by a high intensity pulsed electron beam and failed under fatigue loading conditions have been studied. A surface layer with a nanocrystalline multiphase structure is shown to form during fatigue tests of the samples preliminarily annealed in air. The surface layer structure of the samples after irradiation is found to differ substantially from the structure of the unirradiated samples: a 5-μm-thick surface layer, in which the grain volumes have a subgrain structure, forms.

Оцінка ефективності чисельних методів для обробки результатів вимірювання вдосконаленим ППР-сенсором

In this work there has been investigated the effect of electron beam treatment of the glass substrates surface of sensors based on surface plasmon resonance phenomenon with active gold based layer on the accuracy of determining the angular position of the reflection characteristics in case applying numerical methods for processing direct measurement results: approximation by polynomials of the 2nd 3rd and 4th degrees and processing by midline method. Sensors with different specific powers of electron beam treatment of glass substrates were investigated: 0, 27, and 36 W/mm2. The reflection characteristics for the gold-air interface were investigated. According to the results of experiments and numerical analysis, it was found that the effect of electron beam treatment on the change in the absolute error in determining the minimum reflection characteristics substantially depends on the chosen numerical method. Thus, the improved midline method provides a 6-fold decrease in the absolute measurement error compared to the midline method for samples without processing and almost 12 times for samples with processing power of 27 W/mm2. Moreover, for this method, the smallest absolute error is observed for the power of electron beam treatment 36 W/mm2 and is 0,58 arc sec., which indicates the appropriateness of applying new method. Compared to the approximation methods by polynomials and the midline method, the improved midline method has greater accuracy in determining the minimum reflection characteristics because it depends less on not only its symmetry associated with the optical characteristics of the gold-air transition layer, but also on changes in the intensity of reflected light minimum reflection characteristics. According to the results of calculations based on predefined optical constants from the measured reflection characteristics, it was found that, with a higher irradiation power, the symmetry of the reflection characteristic, the propagation distance and the penetration depth of surface plasmons increase, which is associated with a decrease in surface roughness after electron beam treatment and, as a consequence, a decrease in attenuation fields of surface plasmons. Research can be useful in the development of sensors based on surface plasmon resonance phenomenon and methods for processing measurement results

Effects of Electron Beam Treatment on Amorphous Carbon Nitride Thin Films Grown by Using the Facing Target Sputtering Method

Effects of Electron Beam Treatment on Amorphous Carbon Nitride Thin Films Grown by Using the Facing Target Sputtering Method

Effect of electron-beam treatment of sensor glass substrates for SPR devices on their metrological characteristics

Effect of electron-beam treatment of sensor glass substrates for SPR devices on their metrological characteristics

Investigation of Effect of Electron Beam Surface Treatment of Titanium Alloy Ingots on Structure and Properties of Melted Metal

Based on accumulated experience of application of concentrated power sources for elimination of defects of ingot surface layer it is shown that remelting of surface layer of treated ingot provokes evaporation of alloying elements with high vapor pressure form a liquid pool, i.e. change of composition of treated layer in relation to ingot base. This can indicate the possible change of metal structure since it is determined by content of alloying elements.Ingots of wrought titanium alloys VT3-1, VT-6, VT20, VT22 of 400 and 600 mm diameter and up to 2 m length made by EBM were melted by electron beam for investigation of effect of electron beam treatment of a surface layer on composition, structure and properties of metal of the treated layer. The investigations of mass concentration of alloying elements, penetration depth, macro and microstructure of melted metal layer of treated ingots were carried out.The results of carried works showed that electron beam treatment allows efficient elimination of defects of the surface layer of titanium alloy ingots to 12 mm depth, content of alloying elements corresponds to grade composition, reduction is observed in content of alloying elements, in which vapor pressure is higher than in the alloy base, and respectively rise of content of alloying elements with vapor pressure is lower than in the alloy base. There is insignificant increase of content of interstitial impurities, i.e. oxygen and nitrogen, which do not have obvious effect on mechanical properties of treated metal. It is determined that macrostructure of metal in the treated layer of titanium alloy ingots is characterized with absence of pores and discontinuities, crystals close to equiaxial, the melted layer is formed by finer crystals in comparison with the rest part of the ingot, elongated in solidification direction, i.e. to ingot center. Solidification rates of more than 50 mm/min in the melted layer of titanium alloy ingots provoke two times refining of α-colonies and α-lamellas of ingot grains in comparison with the ingot base.

Influence of Electron Beam Treatment of Co–Cr Alloy on the Growing Mechanism, Surface Topography, and Mechanical Properties of Deposited TiN/TiO2 Coatings

This study examines the effect of electron beam treatment (EBT) of Co–Cr substrate on the film growth mechanism, mechanical properties, and surface topography of TiN/TiO2 coatings deposited by reactive magnetron sputtering. The obtained results and processes that occurred during the deposition are discussed in the context of crystallographic principles, and special attention is paid to the crystallographic orientation and growth mechanism studied by X-ray diffraction (XRD). The mechanical properties were investigated by means of nanoindentation and wear tests. The surface topography was evaluated using atomic force microscopy (AFM). The results obtained in the present study showed that polycrystalline TiN and anatase TiO2 phases were present in all cases. Electron beam treatment of Co–Cr substrate tended to form a reorientation of the microvolumes from (111) to (200) of TiN, leading to a change in the growth mechanism from three-dimensional (Volmer–Weber) to layer-by-layer (Frank–van der Merwe). It was found that the electron beam treatment process did not significantly affect the thickness of the coatings and the deposition rate. The treatment process led to an increase in surface roughness. The higher surface roughness after the EBT process should be appropriate to support cell growth and adhesion on the surface of the deposited bilayer coating. It was demonstrated that EBT of the substrate caused a decrease in hardness of the deposited coatings from 10 to 5 GPa. The observed decrease in hardness was attributed to the change in the preferred crystallographic orientation and film growth mechanism. The hardness of the bilayer coating after the application of EBT of the Co–Cr substrate was much closer to that of human bones, which means that severe stress shielding effect could not be expected. The evaluated coefficient of friction (COF) exhibited significantly lower values in the case of EBT of the substrate compared to the untreated Co–Cr material.

E-beam treatment to guarantee the safety and quality of cherry tomatoes

Abstract The aim of this study was to evaluate the effects of electron beam treatment on microbiological parameters and bioactive content of cherry tomatoes in order to assess the feasibility of irradiation as a post-harvest treatment for this fruit. E-beam inactivation studies of natural cherry tomatoes microbiota and inoculated potential foodborne pathogens (Salmonella enterica; Escherichia coli and Listeria monocytogenes) were performed before and after irradiation and at a storage time of 14 days at 4 °C. A 4 log reduction on mesophilic bacterial population, and no detection of filamentous fungi and foodborne inoculated pathogens was achieved after e-beam treatment at 3.6 kGy and storage. Regarding the effects on bioactive content, the achieved data suggested that an e-beam treatment at 3 kGy could preserve the lycopene content and the antioxidant activity of cherry tomatoes extracts, but the storage time is a determinant factor on its bioactivity. Moreover, the results indicated an antiproliferative effect on human lung cancer cells of lycopene extracts from irradiated and stored cherry tomatoes and no cytotoxicity on human non-cancer cells. Overall the results of this comprehensive study support the feasibility of e-beam irradiation as post-harvest treatment of cherry tomatoes. Industrial relevance Tomatoes constitute the predominant source of lycopene, a bright red carotenoid pigment that has been associated with the prevention of cardiovascular diseases and cancer. The increasing attraction and growing need for functional or bioactive foods, highlight the potential of crops and its bioactive compounds to serve as safe and effective preventive and therapeutic agents. Therefore, food may evolve to be considered a vital aspect of dietary-disease prevention. The development of food processing technologies that extend the shelf-life while guaranty or improve the food safety and functionality, will have a positive impact on both the industry and consumers. As an extension of a previous study, the present research indicated that post-harvest e-beam treatment of cherry tomatoes can be used as an emergent, clean and environmental friendly process to extend the shelf-life of this fruit with safety and preserving its bioactivity.

Effect of Electron-Beam Treatment on Wear-Resistant Coatings Applied by Electroexplosive Sputtering

TiC–Mo, TiC–Ni, TiB2–Mo, and TiB2–Ni coatings applied to the surface of Hardox 450 steel by electroexplosive sputtering are subjected to electron-beam treatment, After electroexplosive application, the surface relief of the coatings includes features such as deformed solidifying microglobules, buildup, microcraters, microcracks, and peeling. After electron-beam treatment, the microglobules, buildup, microcraters, and microcracks disappear from the coating surface. A polycrystalline structure containing cellular elements is formed. After electron-beam treatment, the surface roughness is 1.1–1.2 μm. The thickness of the layers modified by the electron beam in the electroexplosive coatings depends linearly on the surface energy density. The greatest coating thickness is observed when using the TiB2–Mo system; the coating thickness is least for the TiC–Ni system. That may be attributed to the thermophysical properties of the coatings. The following substructures are observed in the coatings: cellular, striated, fragmented, and subgranular. Grains with chaotically distributed dislocations and reticular dislocations are also observed. Electron-beam treatment leads to the formation of composite filled structure over the whole cross section of the remelted layer. The structure formed in this layer is more disperse and uniform than in coatings formed without electron-beam treatment. The inclusions of titanium carbide or titanium diboride in the molybdenum or nickel matrix are 2–4 times smaller than immediately after electroexplosive sputtering. Within the molybdenum or nickel grains and at their boundaries, rounded particles of secondary phase (titanium carbide or titanium diboride) are observed. They may be divided into two classes by size: particles of the initial powder (80–150 nm) that have not dissolved on irradiation; and particles formed on solidification of the melt (10–15 nm). In the electroexplosive powder coatings, the structure is mainly formed by dynamic rotation of the sprayed particles, which form a vertical structure both in the coating and in the upper layers of the substrate. The coatings have excellent operational properties: nano- and microhardness, elastic modulus of the first kind, and wear resistance in dry slipping friction.

Effect of electron beam remelting on the characteristics of HVOF sprayed Al2O3-TiO2 coatings deposited on titanium substrate

The primary objective of this study was to improve the wear resistance of titanium by depositing on its surface a HVOF (high velocity oxygen fuel) sprayed Al2O3-TiO2 coating subsequently remelted by electron beam (EB).The microstructure of the feedstock material, as-sprayed and EB remelted coatings was investigated by scanning electron microscopy (SEM) and X-Ray diffraction techniques (XRD). The effect of EB treatment on the coatings characteristics especially concerning the morphology, the hardness respectively the corrosion and wear behaviour was also analysed.The results indicated that remelting process improved the coating properties in terms of porosity, strength and chemical homogeneity. The coating adherence to the substrate was strengthened by means of metallurgical bonding and interdiffusion processes.The sliding wear resistance and the hardness of the coating were significantly higher in comparison with that of the titanium. The densified material obtained after the EB remelting had the highest sliding wear resistance and its corrosion behaviour was not strongly influenced compared with that exhibited by the substrate material.

Effect of electron beam treatment on structural change in titanium alloy VT-0 at high-cycle fatigue

Changes in the surface of the fractured structure of commercially pure titanium VT1-0 under treatment by low-energy high-current electron beams and the subsequent cycle fatigue to the failure were analyzed by transmission scanning and transmission electron diffraction microscopy. The increase in the fatigue life of samples in 2.2 times after treatment by electron beams was established. An assumption was made that the increase in the fatigue life of titanium, grade VT1-0, was due to the formation of a lamellar substructure conditioned by high-velocity crystallization of the titanium surface layer.

Effect of Electron Beam Treatment in Air on Surface Properties of Ultra-High-Molecular-Weight Polyethylene

In this study, ultra-high-molecular-weight polyethylene (UHMWPE) was treated by an electron beam (EB) in air to obtain polar hydroxyl and carbonyl functional groups, which originated from oxidizing agents, to improve hydrophobicity and cell adhesion (NCTC clone L929). Sample characterization using Fourier transform-infrared spectroscopy revealed the presence of carbonyl oxidation products, whose intensity and surface roughness increased with increasing irradiation dose. The substitution of polar groups into the surface layers of the polymers resulted in a decreased water contact angle. The observed differences in the water contact angle of untreated polymers relative to that of the treated samples can be attributed not only to the differences in their respective molecular composition but also to their distinct roughness values. The treatment conditions affected the adhesion characteristics of fibroblasts. The untreated polymer and the surfaces treated at 10.7 kGy maintained the adhesion, spreading, and proliferation of fibroblasts. The hydrophilic polymer treated at 46.5 and 106.5 kGy maintained only the initial adhesion of fibroblasts. Thus, this study shows that EB treatment is a useful tool for modifying the surface properties of UHMWPE for particular biomedical applications. For example, the initially hydrophobic surface of UHMWPE can be made either hydrophilic or moderately hydrophobic by varying the surface treatment procedure using EB.

Effects of electron beam treatment on cotton linter for the preparation of nanofibrillated cellulose

Nanofibrillated cellulose (NFC) was prepared from cotton linter after electron beam irradiation to investigate its effects on the manufacturing efficiency of the NFC preparation and the property changes by the treatment. Mechanical device (Super Masscolloider) was used to prepare the NFC and its passing frequency for each NFC preparation was recorded. More electron beam irradiation resulted in less passing frequency. Alpha cellulose content, molecular weight, crystallinity index, and thermal decomposition behavior of each treatment were lowered by electron beam treatment (10 and 100 kGy) and grinding process. NFC films were prepared to investigate their mechanical properties. There were little changes in tensile properties of the NFC films.

Effects of electron beam treatment on Ti(1−x)AlxN coatings on steel

Ti(1−x)AlxN hard coatings were prepared by reactive magnetron sputtering onto steel substrates. Composition and mechanical properties of the coatings could be varied using different target combinations. The prepared samples were subsequently treated by a high energy (60 keV) electron beam (EB). Martensitic hardening of the steel material occurred. It was found that composition and mechanical properties of the coatings remained nearly equal compared to untreated sample surfaces. The hardening depth profiles of the samples were strongly influenced by the coating. In the coating-interface region significant changes of the composition profile, caused by the electron beam (EB) processing, were observed. The coating adhesion, evaluated using scratch tests, could be clearly improved if proper Electron beam hardening (EBH) parameters were chosen. The unequal hardening profiles observed after EBH on coated and uncoated samples can be explained by different backscattered electron yields and by different electron ranges.