How to Harvest Haylage Bales in Sustainable Agriculture

Storing silage in round bales (balage) is a commonly used method for preserving forage for use as stock fodder that has a higher nutritional content than hay. Baling at the optimum density is important for ensuring ideal fermentation conditions. In the manuscript, we present the research methodology and the results of the experiment. We did experiments over the density of haylage bales. We investigated the effect of the moisture content in the harvested material, the length of the cut material and the pressing pressure in the round baler. We used the Barenbrug BG-5 forage mix at different moisture content levels (69, 63, 56, 49, and 42%), that was either unchopped or chopped by the round baler’s cutter bars (312 and 183 mm length) and baled at three different pressing pressures (0.9, 1.4, and 1.8 MPa). The results showed that forage density in the bales reached the highest value at a moisture content of 56% and a pressing pressure of 1.8 MPa, with the forage chopped by the cutter bars.

Hot press sintering effects and wear resistance of the Al-B4C composite coatings of an AA-2024 alloy

In this study, the surface of AA-2024 alloy substrate was coated with an Al-B4C reinforced composite using hot press sintering. Al and B4C powders were synthesized by mechanical alloying. To this end, four samples were prepared. As a reference sample, AA-2024 substrate was coated with pure Al powder under 110 MPa pressure. In the other samples, the AA-2024 substrate was coated with metal matrix composites (MMCs) contained in Al-5 wt.-% B4C at 90, 110 and 130 MPa. The microstructure of the transition zone formed between the AA-2024 substrate and the coating layer of the coated samples, the microstructure of the Al/B4C MMCs coating, the macro hardness, the linear reciprocating and forth wear resistance of the coating layer were investigated. In addition, an optical microscope (OM), scanning electro microscope (SEM) images and EDS analysis of the microstructure were used. It was observed that the B4C powders were homogeneously distributed in the Al matrix in the microstructure of the coating layer. It was also found that the gaps between the grains in the microstructure of the coating layer and their size decreased with an increase in pressing pressure. Accordingly, it was concluded that macro hardness increased and weight loss decreased.

Composite materials based on Al2O3‒SiC‒TiB2 obtained by SHS extrusion and their hightemperature annealing

As a result of the combination of the processes of selfpropagating high-temperature synthesis (SHS) and shear high-temperature deformation, realized in the method of SHS-extrusion, ceramic rods based on Al2O3‒SiC‒TiB2 were obtained. The influence of technological parameters of the process (delay time, pressing pressure) on the length of the obtained rods has been studied. The obtained materials were annealed in the range 1000‒1300 °C, and the microstructure and phase composition of the materials were studied before and after heat treatment.

Sintered material based on titanium carbide to increase the service life of slide gates

A new cermet material based on titanium carbide with a complex bond consisting of nichrome and nickel, additionally hardened with chromium carbide and a solid solution of chromium in titanium carbide, has been obtained. The influence of the technological parameters of the SHS-extrusion method (the delay time before the application of pressure, the pressing pressure, the speed of the press plunger movement) on the length of the extruded rod is studied, the optimal parameters are found. The microstructure and phase composition of the obtained material was investigated, the physical and mechanical characteristics were measured, and a comparison with analogs was given. It is shown that the microstructure, phase composition, and crystal lattice parameters of the phases do not change depending on the diameter of the extruded rod.

Electron beam sintering of Mn-Zn ferrites using a forevacuum plasma electron source

The article presents the results of electron beam sintering without applying pressure of Mn-Zn ferrites in an oxygen environment. Samples for sintering were made from fine powders and pressed at various pressures into compacts in the form of disks. Measurements of the elemental composition and structure of the sample after sintering are presented. It is shown that the result of sintering depends on the pressing pressure of compacts, time and temperature of sintering.

Influence of electron-beam heating modes on the structure of composite ZrO2-Al2O3 ceramics

The article presents the results of electron beam sintering of composite ceramics based on Al2O3 and ZrO2 powders. Samples were made with different contents of Al2O3 and ZrO2 components and different pressing pressures. Sintering was carried out in vacuum at a helium pressure of 30 Pa. An electron beam generated by a forevacuum plasma electron source was used for sintering. It is shown that the sintering result depends on the pressing pressure and the percentage of components. The influence of the geometry of the samples and their composition on the temperature drop over their volume during sintering has been determined.

INVESTIGATION OF THE DENSITY OF A FIBROUS CELLULOSE MATRIX FOR A HEAT-INSULATING POLYMER COMPOSITE MATERIAL AT LOW PRESSING PRESSURES

Для теплоизоляционных полимерных композиционных материалов (ПКМ) с наполнителем из целлюлозных волокон одним из актуальных вопросов является изменение плотности волокнистой матрицы под действием внешних механических нагрузок. Предметом экспериментального исследования явились образцы разрыхленной небелёной древесной сульфитной целлюлозы из хвойной древесины в воздушно-сухом состоянии. Цель исследования – оценка изменения насыпной плотности разрыхленной целлюлозы от величины давления прессования при малых давлениях прессования. В экспериментальных исследованиях использован метод денсиметрии. Из целлюлозной папки в лабораторных условиях получены образцы разрыхленной целлюлозы путём механического разволокнения. Использован лабораторный колковый рыхлитель роторного действия. Разрыхление проведено при окружной скорости ротора 50 м/с. Давление прессования варьировалось от 0 до 7,5 кПа. Получены образцы разрыхленноё целлюлозы с насыпной плотностью от 11,1 до 100,0 кг/м3. Эксперименты проведены с трёхкратным повторением. Показано, что при увеличении давления прессования насыпная плотность целлюлозы стабильно возрастает. В исследованном диапазоне давлений прессования уплотнение целлюлозы проходит в два этапа. На первом этапе при давлении прессования от 0 до 5 кПа насыпная плотность возрастает от 11,1 до 87,5 кг/м3. На втором этапе, при давлении прессования свыше 5 кПа, насыпная плотность возрастает с 87,5 до 100 кг/м3. На втором этапе замедление нарастания насыпной плотности при росте давления прессования может быть обусловлено деформацией элементарных волокон целлюлозы. Результаты экспериментального исследования могут быть применены для создания теплоизоляционных ПКМ на основе целлюлозных волокон. For heat-insulating polymer composite materials (PCM) with a cellulose fiber filler, one of the topical issues is the change in the density of the fiber matrix under the influence of external mechanical loads. The subject of the experimental study was samples of loosened unbleached wood sulfite cellulose from coniferous wood in an air-dry state. The aim of the study is to assess the change in the bulk density of loosened pulp from the value of the pressing pressure at low pressing pressures. In experimental studies, the method of densimetry was used. Samples of loosened cellulose were obtained from the pulp folder under laboratory conditions by mechanical de-fibration. A laboratory rotary chopper was used. Loosening was carried out at a circumferential rotor speed of 50 m / s. The pressing pressure varied from 0 to 7.5 kPa. Samples of loosened cellulose with a bulk density from 11.1 to 100.0 kg/m3were obtained. The experiments were carried out in three-fold repetition. It is shown that with an increase in the pressing pressure, the bulk density of cellulose steadily increases. In the studied range of pressing pressures, the pulp compaction takes place in two stages. At the first stage, at a pressing pressure of 0 to 5 kPa, the bulk density increases from the initial value 11.1 to 87.5 kg / m3. At the second stage, when the pressing pressure exceeds 5 kPa, the bulk density increases from 87.5 to 100 kg/ m3. At the second stage, the slowdown in the increase in bulk density with an increase in the pressing pressure can be caused by the deformation of the elementary cellulose fibers. The results of the experimental study can be used to create heat-insulating PCM based on cellulose fibers.

Influence of the firing temperature on the dielectric properties of ceramics based on barium titanate

The object of the research is the firing temperature of ceramic materials based on barium titanate. In laboratory conditions, barium titanate was synthesized from raw materials of barium carbonate and titanium dioxide using ceramic technology, taking into account the stoichiometric composition of the compound. In order to study the effect of the firing temperature on the properties of the ceramic material, three temperatures were selected: 1270, 1300, and 1350 °C. The physical properties of the samples (imaginary density, water absorption, open porosity) were determined by the method of hydrostatic weighing in water. The samples were saturated with water after their preliminary evacuation. The dielectric characteristics of the obtained materials were measured on an E7-8CLR automated device (Ukraine) at a frequency of 1 kHz. The structural and morphological features of ceramics based on synthesized barium titanate were investigated by direct scanning electron microscopy and X-ray phase analysis. On the basis of the complex of studies carried out, the technological parameters of the production of ceramics were selected. Thus, the duration of grinding at the first and second stages is 10 and 30 minutes; moisture content of the press powder – 8 %; pressing pressure – 20 MPa; temperature of the first firing – 1000 °С; temperature of the second firing – 1350 °C. The regularity of the change in the dielectric constant on the firing temperature of ceramics based on barium titanate was established. The investigated samples, obtained according to the given technological regime, are characterized by the following indicators: dielectric constant – 259.9; open porosity – 0.02 %; water absorption – 0.01 %; imaginary density – 5.45 g/cm3. The resulting material can be used to create composite ceramic materials that protect biological and technical objects from the effects of electromagnetic radiation, and can also be used to create new functional materials for space, aerospace, electronic engineering and medicine.

Influence of hot pressing technological parameters on plywood bending properties

Different types of wood are used to manufacture of various wood products. In direct production processes, additional resources such as energy, adhesives, labor, etc. are also used. In line with sustainable environmental policies, all resources must be used more rationally, while simultaneously increasing the efficiency of the direct production processes. This research examined whether it is possible to reduce energy and labor resources in the technological process of hot pressing of birch plywood (nominal thickness 9 mm), by varying the holding time under pressure, pressure, and adhesive consumption. The Box-Behnken experimental design for a multifactor experiment was used to investigate the influence of technological parameters of plywood pressing. The highest strength in static bending both parallel and perpendicular to the plywood grain was achieved by pressing plywood with the following gluing parameters: highest pressing pressure, 3.2 MPa; minimal holding time under pressure, 9 minutes; and average phenol-formaldehyde adhesive consumption 150 grams per square meter.

Optimization of structure matrix of mold forms

Purpose. Optimization of the method of design and calculation of the composite matrices of molds for the manufacture of products from powder materials. Research methods. Analysis of stresses in the walls of solid and composite thick-walled cylinders and their existing calculations. Results. The peculiarities of stress formation in the wall of solid and composite thick-walled cylinders under the action of internal pressure are investigated. The possibility of applying the obtained results to determine the strength and stiffness of the wall of the mold for the manufacture of products from powder materials is analyzed. Limitations in ensuring the strength of the matrix by only increasing its thickness are determined. It is shown that the use of a matrix composed of an inner cylinder and an outer holder allows to use optimal stress redistribution in the walls of such matrix in order to reduce the size and, accordingly, save materials for its manufacture. The possibility of using various, better adapted materials for the manufacture of the inner wall of the matrix and permiting the reduction of the cost of manufacturing the mold are analyzed. The method of calculation of stresses in dangerous points of walls of a matrix at an estimation of their strength and stiffness is generalized. Formulas for determination of the guaranteed tension which will provide effective redistribution of stresses in walls of the composite matrix under the set operating conditions are given. Scientific novelty. Approaches to the analysis of stresses in the walls of composite matrices of molds under the influence of internal pressure are optimized and generalized . Mathematical dependences are given, which make it possible to determine the optimal dimensions of mold elements at action of pressing pressure. Practical value. The principles of design and methods of calculation of composite matrices of molds for the manufacture of products from powder materials are proposed.