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Preparation and properties of porous zinc material
Ryšťák, Jaroslav ; Fintová, Stanislava (referee) ; Doležal, Pavel (advisor)
Bachelor thesis is focused on preparation of bulk material prepared from zinc powder by cold pressing followed by sintering. Topic of the work includes characterization of prepared material depending on the choice of the compaction process conditions. Bulk material is characterized by physical-mechanical tests, structure and porosity. Thesis solving and focuses on study and control of processes during bulk material preparation and description of the processes from physically-chemical point of view of the structure creation and final material properties.
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Preparation and Characterization of Porous Magnesium Based Materials
Březina, Matěj ; Pacal, Bohumil (referee) ; Vojtěch, Dalibor (referee) ; Ptáček, Petr (advisor)
Bulk magnesium materials produced nowadays via powder metallurgy are based on a vastly extensive technological spectrum, which makes it possible to create a wide range of materials. This work focuses on the preparation of bulk materials from magnesium powder by cold pressing and hot pressing, sintering and field assisted sintering. The bulk materials were prepared in a series of compacting pressures from 100 MPa to 500 MPa and the sintering temperatures were selected in the range of 300 ° C to 600 ° C in order to characterize the influence of the manufacturing conditions and technology on the final properties of bulk materials. Prepared materials were evaluated in terms of microstructure, hardness, microhardness, three-point bend test, and fractography. From the hot pressed materials, the samples prepared at 400 and 500 MPa and 400 °C had the highest strength and hardness. The classic sintering of magnesium in the furnace with argon atmosphere proved to be ineffective due to the oxide layer on the surface and the presence of oxygen in technical argon. The SPS sintering (Spark Plasma Sintering) was the more effective with the lower applying pressure used to make the preforms and with the higher applied pressure during the SPS process itself. Highest strength and hardness were achieved in this case of materials sintered at 600 ° C prepared from free powder and the most porous preform (100 MPa). The bulk materials were prepared using all methods used, but the properties of these materials varied considerably depending on the technology used.
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Preparation and properties of bulk material from magnesium powder
Ruttkayová, Veronika ; Pacal, Bohumil (referee) ; Doležal, Pavel (advisor)
Diploma thesis focuses on preparation and characterization of bulk material prepared from pure magnesium powder. The topic includes all the parts of process of bulk material preparation, sintering at hot pressing, diffusion processes and structurally-mechanical properties with respect to final material porosity of the produced material. Thesis solving focuses on study and control of processes during bulk material preparation and description of the processes from physically-chemical point of view of the structure creation and final material properties.
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Design of bulk cold forming technology for bicycle part
Kubíček, Lubomír ; Šlais, Miroslav (referee) ; Forejt, Milan (advisor)
The diploma thesis is dealt with a project of a new manufacture method of a bicycle´s part. The part is a brake drum, which is the necessary part of a free-running charge. In an intro-duction of the diploma thesis is described a nowdays manufacture technology and its deficiencies. According to the nowdays manufacture technology was designed a new one, which is based on a cold volumetric shanking. The shanked hemihedron is consequently shaped according to the current technology. After the operation of cold shaping an instrument is projected. The project of the shaping technology is filled up by the calculation of the essential parameters, including an arrangement of the instrument and the process. An economical evaluation of the new process of the brake drum is stated and its advantages and disadvantaged were selected.
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Preparation of Mg-Al based bulk materials via powder metallurgy
Jakůbek, Zdeněk ; Fintová, Stanislava (referee) ; Březina, Matěj (advisor)
This diploma thesis is focused on preparation of Mg-Al based bulk materials via powder metallurgy. The bulk materials were prepared by cold pressing, cold pressing followed by sintering, cold pressing followed by sintering and artificial aging, SPS (spark plasma sintering), SPS followed by solution annealing, SPS followed by solution annealing and artificial aging. The prepared materials were characterized in terms of microstructure and physical and mechanical properties. The properties of the prepared materials differed depending on the method of preparation and Al content. All materials after heat treatment were consisted of solid solution (Mg), intermetallic phase Mg17Al12 and MgO. The composition of the materials depended on Al content. Sintering by the SPS method resulted in material with better mechanical properties compared to materials whose first step of preparation was cold pressing.
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Ověření účinnosti a využití lisu pro lisování olejnatých semen
Jackson, Zdena
ABSTRACT The diploma thesis called "Verification of efficiency and utilization of oilseed presses" is focused on the issue of oil pressing with emphasis on process efficiency and oil yield. A measurement was carried out at the Institute of Horticultural Engineering, the purpose of which was to verify the screw press of a small capacity UNO FM 3 F of Farmet, Czech Republic in the pressing of grape seed oil. The experimental measurements were carried out in 2018-2019 for seed samples provided by Agropol Mikulov, which were separated from the marc. The results of the work are divided into two main parts – Cold oil pressing and Soxhlet oil extraction and Economic aspects of wine production lines designed for seed processing and oil production. The seeds were compressed at 20, 40, 60, 80 and 100 rpm. The results confirmed that with increasing speed the pressing time was reduced. At higher speeds during compression, the amount of sediment increased. While pressing from 20 to 80 rpm, the oil yield decreased from 9.87 % to 9.67 % while the pressing capacity increased from 0.86 liter/hour to 2.17 liter/hour. It was no longer possible to press at speed 100 rpm, the machine was too overloaded. The Soxhlet extraction apparatus with hexane as solvent was used to determine the total oil content. Seed oiliness was 12.85 %. The market value of cold pressed oil from grapevine seeds, used in gastronomy or as a massage product, is 990-1100 CZK / liter. With an average crude oil yield of 8 %, from 1 ton of seeds, 80 liters of oil can be pressed, which represents the currently expected yield of 80-88 thousand. CZK. The results of the economic evaluation show that with all the costs involved in the oil production, including the investment costs for the production line, the return on investment is 3,23 years. From the results of the economic evaluation of the experiment at 9,8 %, from 1 ton of seeds the expected yield of 98 l of oil is 97 020 - 107 800 thous. CZK. The return on investment period was 1,92 years.
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Ověření použití sekundárních produktů po lisování oleje v kosmetickém průmyslu
Huláková, Lenka
The thesis describes the pressing of oils from fruit species, presents their selected quality parameters and evaluates the possibilities of their application in the production of cosmetics. The oil was pressed from almond, hazelnut, royal, apricot, peach, currant and rosehip seeds. Particular oils were obtained by cold pressing to produce the secondary products used. Selected substances such as fatty acid content. It also included the identification of qualitative parameters such as peroxide number, acidity number, oil acidity, oil saponification and iodine content in oils. Results show high MUFA content. Oil with its highest content is walnut (85.97%). The predominant acid in oils is oleic acid. Plum oil has the best antioxidant stability. The highest acid number is apricot oil (3.55 mg KOH.g-1). Peach oil (351,60 mg KOH / g oil) has the highest saponification number. The highest iodine number has almond oil (54,50 g.l2.100 g-1). Oils and secondary products have been used in the manufacture of cosmetic products. The choice of cosmetic products was based on market research. They were inspired by current cosmetic trends.Formula clause:The reason for postponing the publication of final thesis entitled Verification of using the secondary products after oil pressing in the cosmetic industry is the use of results of work for application output, cooperation with the commercial sector and further possible commercialization. Estimated delay is three years.
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Ověření účinnosti šnekového lisu při lisování olej ze semen ovocných druhů
Gertner, Marek
The aim of this thesis was to conduct an experiment in which the efficiency and performance of a screw press were monitored during various modes of operation. The theoretical part of the thesis was focused on a more detailed specification of selected types of nuts. This part also contains a description of individual types of nut trees and their fruits in terms of their practical usage and substances contained. Another objective was to examine the significance and application of nut oils in individual domains of human activity, such as industry, gastronomy, pharmacy, cosmetics, and others. Last but not least, the technical capacities for ensuring mechanical pressing with screw press were introduced and described. The practical part was focused on the process of mechanical pressing using a Farmet UNO screw press. In the first part of the experiment, differences in performance and extraction yield were observed depending on the type of nut being pressed, but also on substances contained in extracted oils. The second part of the experiment focused on pressing of a single type of material, namely peanuts. The performance and extraction yield of the press was observed during three chosen modes of operation. Finally, data regarding performance and extraction yield of Farmet UNO press was processed and evaluated. This was done from the perspective of differences between pressed materials and differences between individual modes of operation. Results of laboratory analyses of substances contained in extracted oils were also processed and compared. This diploma thesis produced rather demonstrable results that can be taken into consideration during practical application.
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Preparation of Mg-Al based bulk materials via powder metallurgy
Jakůbek, Zdeněk ; Fintová, Stanislava (referee) ; Březina, Matěj (advisor)
This diploma thesis is focused on preparation of Mg-Al based bulk materials via powder metallurgy. The bulk materials were prepared by cold pressing, cold pressing followed by sintering, cold pressing followed by sintering and artificial aging, SPS (spark plasma sintering), SPS followed by solution annealing, SPS followed by solution annealing and artificial aging. The prepared materials were characterized in terms of microstructure and physical and mechanical properties. The properties of the prepared materials differed depending on the method of preparation and Al content. All materials after heat treatment were consisted of solid solution (Mg), intermetallic phase Mg17Al12 and MgO. The composition of the materials depended on Al content. Sintering by the SPS method resulted in material with better mechanical properties compared to materials whose first step of preparation was cold pressing.
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Preparation and Characterization of Porous Magnesium Based Materials
Březina, Matěj ; Pacal, Bohumil (referee) ; Vojtěch, Dalibor (referee) ; Ptáček, Petr (advisor)
Bulk magnesium materials produced nowadays via powder metallurgy are based on a vastly extensive technological spectrum, which makes it possible to create a wide range of materials. This work focuses on the preparation of bulk materials from magnesium powder by cold pressing and hot pressing, sintering and field assisted sintering. The bulk materials were prepared in a series of compacting pressures from 100 MPa to 500 MPa and the sintering temperatures were selected in the range of 300 ° C to 600 ° C in order to characterize the influence of the manufacturing conditions and technology on the final properties of bulk materials. Prepared materials were evaluated in terms of microstructure, hardness, microhardness, three-point bend test, and fractography. From the hot pressed materials, the samples prepared at 400 and 500 MPa and 400 °C had the highest strength and hardness. The classic sintering of magnesium in the furnace with argon atmosphere proved to be ineffective due to the oxide layer on the surface and the presence of oxygen in technical argon. The SPS sintering (Spark Plasma Sintering) was the more effective with the lower applying pressure used to make the preforms and with the higher applied pressure during the SPS process itself. Highest strength and hardness were achieved in this case of materials sintered at 600 ° C prepared from free powder and the most porous preform (100 MPa). The bulk materials were prepared using all methods used, but the properties of these materials varied considerably depending on the technology used.
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