|
| |
|
|
Properties of moulding mixtures of mixed bentonites after repeated use
Virgl, Vítězslav ; Neudert, Alois (referee) ; Kaňa, Václav (advisor)
High class mold is required for high quality castings. At present, the demands on molding materials are being extended by adding the strict requirement of environmentalists. A suitable variant that meets both demands are green sand molds. The goal of the thesis is to repeatedly cast experimental castings into molds made of 4 types of green sand mixtures. The technological properties of the molds will be compared, the degree of bentonite degradation will be assessed and the surface quality of castings will be assessed according to the amount of adherent molding mixture.
|
|
| |
|
|
Influence of chemical composition, casting temperature and the used deoxidation on technological properties of austenitic chrome-nickel steels
Myška, Martin ; Dulava, Martin (referee) ; Záděra, Antonín (advisor)
The thesis deals with austenitic stainless steel ČSN 42 2930, ASTM A351 CF8 and evaluates its mechanical and technological properties. The first part of this work is focused on properties of austenitic steels, it describes the process of melting and casting of steel on the basis of the realized experiments. It also deals with the mechanical properties of the used steel. The second section of the thesis is dedicated to the historical development of the maximum fluidity tests and main factors affecting the maximum fluidity of alloys. Maximum fluidity values have been processed on the basis of different casting temperatures of the maximum fluidity tests of the used steel. The third part of the work examines the effect of the casting temperature on the feeding distance of the used steel as well as the influence on its shrinkage rate.
|
|
|
Relationship between petrographic parameters and technological properties of clastic sedimentary rocks used for crushed stone
Čermák, Martin ; Přikryl, Richard (advisor) ; Krutilová, Kateřina (referee)
This diploma thesis is focused on the finding and describing of the relationships between petrological parameters and technological properties of rocks used for the production of aggregates (crushed stone). Rock specimens were selected from a geological area of Culm (Lower Carboniferous age) in the area of Nízký Jeseník Mts. and Drahanská vrchovina uplands in the Czech Republic. Studied localities were selected on the basis of the current quarrying operations and also to represent the different strata. The six studied localities encompass Kobylí, Chabičov, and Bělkovice where Horní Benešov formation of Nízký Jeseník is exposed. Locality Valšov represents Andělské Hory formation and locality Nová Ves and Loštice represent Protivanov formation of Drahanská vrchovina uplands. Two specimens were taken from the locality Loštice (one from the second cut because there are produced low-grade aggregates and the third cut where high quality crushed stone is produced). A detailed mineralogical-petrographic examination of the samples was the first step, in an attempt to obtain their mineralogical composition and to identify the major rock-forming clasts. Thin sections were examined by standard polarizing microscopy. The auxiliary UV lamp and thin sections saturated by fluorescent substance were used for the...
|
|
| |
|
|
Influence of chemical composition of steel on structure and properties of stainless steels
Valenta, Pavel ; Čech, Jan (referee) ; Záděra, Antonín (advisor)
The thesis is focused on high-alloy austenitic and austenitic-ferritic (duplex) steel. The theoretical part includes research about high-alloy steels and basic introduction to this issue. In the practical part of the test there were casted refractory austenitic steel 30CH3N17G2L, duplex stainless steel 1.4462, low carbon steel and high carbon steel. On the castings of austenitic steel were made mechanical and technological tests. There were evaluated the effects of different casting temperature and casting wall thickness to the microstructures and macrostructures of steel, tensile strength and charpy impact tests. The technological tests compared technological properties of these steels.
|
|
|
Comparison of quality of milk from conventional and organic farming
Cermanová, Ivana ; Vítová, Eva (referee) ; doc.Ing.Oto Hanuš, Ph.D. (advisor)
The diploma thesis focuses on the comparison of milk quality in two different ways of farming, conventional and organic farming. Almost a hundred parameters on the set of 64 bulk milk samples were monitored. The theoretical part of the paper describes the composition of cow's milk, its technological and hygienic properties and it notes the nutritional impact of milk and milk products. It also mentions the most important legal definition of organic farming. Experimental part describes the setting of the experiment and mentions the methods used to analyze milk samples for individual parameters and it details the ten selected determination. The difference in measured values of various milk indicators depending on the dairy farm was observed by using statistical methods and an explanation was suggested in the case of the statistical significance. The thesis was based on the cooperation of the Faculty of Chemistry VUT Brno and a National reference laboratory for raw milk at the Research Institute for Cattle Breeding in Rapotin.
|
|
|
Non-ferrous alloys and their use in practice
Měřinský, Ivo ; Mikulka, Vít (referee) ; Staňková, Markéta (advisor)
This work introduces us with non-ferrous metal alloys and their applications in industry. The area is dedicated to the most widespread copper and aluminium alloys, less used alloys, such as magnesium, titanium, gold and silver alloys. For each alloy is given its manufacturing technology, distribution according to different perspectives and their properties. At the end of each chapter you can meet with examples of using alloys in practice.
|
|
|
Technological applications of cemented carbide tools
Kolomazník, Aleš ; Humár, Anton (referee) ; Prokop, Jaroslav (advisor)
bachelors thesis is on focused on the task:specification and analysis of technological application conditions of cutting tools Carbide.It consists of three parts.The first part deals wiht the development of SK,the nature and properties of sintered carbides.The second part focuses on the technological conditions of parameters of the job application Carbide.The goal was getting to know the structure,production,properties and applications
|
guest ::
