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EN
In this work the effect of Mg addition on structure as well as kinetics of crystallisation of Zn-Al-Cu cast alloy was presented. To the zinc alloy was added 0.1% mass of Mg. The alloy was cast into a metal mould. Thermo-derivative analysis was performed using the UMSA platform (Universal Metallurgical Simulator and Analyzer). The investigated alloys were freely cooled down with a rate of 0.1°C s-1. For the structure analysis were used results obtained using light microscopy, scanning and transmission electron microscopy.
EN
Cast zinc alloys have similar properties to aluminium alloys. The differences are due to the lower melting point and higher density. Zinc has a density of 7.14 g/cm3, a melting point of 419.5°C and the boiling temperature of 906º C. In the temperature range from 150 to 200°C, zinc has good susceptibility to plastic deformation. It is also resistant to atmospheric factor influence, but is not resistant to acids. The main use of zinc alloy, is the production of thin-walled casts that require high precision. Zinc alloys are also used for die casting moulds, housings and covers as well as a variety of devices that are used in the precision industry, electrical engineering, automotive and construction industry. Properly performed chemical modification leads to improve of properties of the produced castings. Therefore it is very important to know how the cast structure with the change of the chemical composition by adding metallic modifiers to the liquid metal. In this work there was studied the effect of chemical modification of cast zinc alloy on the properties and microstructure of the alloys before and after modification. Modified alloys were prepared by adding modifiers in the range of 0.1% to 1% in form of Ti- Sr and B as aluminium master alloy and then cast into the metal moulds. Next the thermo-derivative analysis was performed of the modified Zn-Al-Cu alloy, the microstructure investigation was carried out using light microscopy and scanning electron microscopy with EDS X-ray microanalysis usage as well as hardness was measured of the modified Zn-Al-C alloys.
3
Content available remote Microstructure investigations of cast Zn-Al alloys
EN
Purpose: The goal of the presented investigations was to evaluate to possibility of application of popular modifiers for chosen types of zinc alloys. The special aim of this work is to determine the influence of alloy modification on the crystallisation kinetics and microstructure of the cast zinc alloy. This research work presents also the investigation results of derivative thermoanalysis performed using the UMSA device. The material used for investigation was the ZnAl8Cu1 alloy. Design/methodology/approach: For phase determination there were used electron microscope techniques like SAD diffraction investigations which were carried out on the 200 kV transmission electron microscope. The UMSA (Universal Metallurgical Simulator and Analyser) device allows it to determine the specific melting process, influence of the cooling rate on the crystallization of phases and eutectics of the investigated alloys. Cooling rate influences the microstructure and properties of the investigated zinc cast alloys. Findings: Change of the crystallization kinetics allows it to produce materials with improved properties, which are obtained by: microstructure refinement, reduction or elimination of segregation. Research limitations/implications: The material was examined metallographically and analysed qualitatively using light and scanning electron microscope as well as the area mapping and point-wise EDS microanalysis. The performed investigation are discussed for the reason of an possible improvement of thermal and structural properties of the alloy. Practical implications: The investigated material can find its use in the foundry industry; an improvement of component quality depends mainly on better control over the production parameters Originality/value: Investigations concerning the development of optimal chemical composition and production method of zinc-aluminium alloys with selected rare earth metals with improved properties compared to elements made of alloys with appliance of traditional methods, will contribute to a better understanding of the mechanisms influencing the improvement of functional properties of the new.
4
Content available remote Microstructure investigations of cast Zn-Al alloys
EN
Purpose: The goal of he presented investigations was to evaluate to possibility of application of popular modifiers for chosen types of zinc alloys. The special aim of this work is to determine the influence of alloy modification on the crystallisation kinetics and microstructure of the cast zinc alloy. This research work presents also the investigation results of derivative thermoanalysis performed using the UMSA device. The material used for investigation was the ZnAl8Cu1 alloy. Design/methodology/approach: For phase determination there were used electron microscope techniques like SAD diffraction investigations which were carried out on the 200 kV transmission electron microscope. The UMSA (Universal Metallurgical Simulator and Analyser) device allows it to determine the specific melting process, influence of the cooling rate on the crystallization of phases and eutectics of the investigated alloys. Cooling rate influences the microstructure and properties of the investigated zinc cast alloys. Findings: Change of the crystallization kinetics allows it to produce materials with improved properties, which are obtained by: microstructure refinement, reduction or elimination of segregation. Research limitations/implications: The material was examined metallographically and analysed qualitatively using light and scanning electron microscope as well as the area mapping and point-wise EDS microanalysis. The performed investigation are discussed for the reason of an possible improvement of thermal and structural properties of the alloy. Practical implications: The investigated material can find its use in the foundry industry; an improvement of component quality depends mainly on better control over the production parameters. Originality/value: Investigations concerning the development of optimal chemical composition and production method of zinc-aluminium alloys with selected rare earth metals with improved properties compared to elements made of alloys with appliance of traditional methods, will contribute to a better understanding of the mechanisms influencing the improvement of functional properties of the new.
5
Content available remote Light and electron microscope investigations of cast Zn-Al alloys
EN
Purpose: The aim of this work is to determine the influence of alloy modification on the crystallisation kinetics and microstructure of the cast zinc alloy. This research work presents also the investigation results of derivative thermoanalysis performed using the UMSA device. The material used for investigation was the ZnAl8Cu1 alloy. Design/methodology/approach: approach The UMSA (Universal Metallurgical Simulator and Analyser) device allows it to determine the specific points of the solidifying alloy, including: Influence of the chemical concentrations of the modifiers, alloying additives, parameters of the melting process, influence of the cooling rate on the crystallization of phases and eutectics of the investigated alloys. Cooling rate influences the microstructure and properties of the investigated zinc cast alloys. For phase determination electron diffraction investigations were performed carried out on the transmission electron microscope. Findings: Change of the crystallization kinetics allows it to produce materials with improved properties, which are obtained by: microstructure refinement, reduction or elimination of segregation. Research limitations/implications: The material was examined metallographically and analysed qualitatively using light and scanning electron microscope as well as the area mapping and point-wise EDS microanalysis. The performed investigation are discussed for the reason of an possible improvement of thermal and structural properties of the alloy. Practical implications: The investigated material can find its use in the foundry industry; an improvement of component quality depends mainly on better control over the production parameters. Originality/value: Investigations concerning the development of optimal chemical composition and production method of zinc-aluminium alloys with selected rare earth metals with improved properties compared to elements made of alloys with appliance of traditional methods, will contribute to a better understanding of the mechanisms influencing the improvement of functional properties of the new.
6
Content available remote Crystallisation kinetics of the Zn-Al alloys modified with lanthanum and cerium
EN
Purpose: The aim of the investigation is to determine the influence of modification on crystallisation kinetics on microstructure of the cast zinc alloy. This research work presents also the investigation results of derivative thermoanalysis performed using the UMSA device. The material used for investigation was the ZnAl8Cu1 alloy. Design/methodology/approach: The UMSA device (Universal Metallurgical Simulator and Analyser) allows it to determine the characteristic points of the crystallised alloy including: determination of the influence of alloy modifiers, alloying additives, melting process parameters, cooling rate influence on phase and eutectics crystallisation of the investigated alloys. In was fund that cooling rate has an influence an microstructure and mechanical properties of the cast zinc alloys. Findings: Crystallisation kinetics change makes it possible to produce materials with improved properties, which are obtained by: microstructure refinement and decrease or elimination of the segregation phenomenon. Research limitations/implications: The material was examined metallographic and analysed qualitatively using light and scanning electron microscope as well as the area mapping and point-wise EDS microanalysis. The performed investigation are discussed for the reason of an possible improvement of thermal and structural properties of the alloy. Practical implications: The investigated material can find its use in the foundry industry; an improvement of component quality depends mainly on better control over the production parameters. Originality/value: value Investigation concerning the elaboration of optimal chemical composition and production method of zinc-aluminium alloys modified with chosen rare earths metals with enhanced properties compared to elements performed from traditional alloys and production methods, makes it possible to achieve a better understanding of mechanisms influencing improvement of mechanical properties of the new developed alloys.
7
Content available remote Crystallization kinetics of Zn alloys modified with Ce, La, Sr, Ti, B
EN
Purpose: This paper presents the investigation results of cooling rate influence on microstructure of the Zn-Al cast alloy. Thermo-derivative analysis of the investigated alloys was performed using the UMSA device (Universal Metallurgical Simulator and Analyzer). This device makes it possible to characterise the important points of the crystallised alloy diagram including: phase and eutectics crystallisation, as well liquidus/solidus points. The material used for investigation was the ZL8 alloy. Design/methodology/approach: Moreover the analysis of cooling rate influence on the derivative curve changes was performed as a result of the measured crystallisation kinetic changes. For the assessment of the cooling rate influence on the mechanical properties also hardness measurements were performed using the Rockwell hardness device. Findings: The treated sample is without holes, cracks and defects as well as has a slightly higher hardness value compared to the as-cast material. Research limitations/implications: Microstructure and mechanical properties investigations of the investigated alloy was performed for the reason of alloying additives influence on alloy microstructure and properties change, the microstructure was analyzed qualitatively using light and scanning electron microscope as well as the area mapping and point-wise EDS microanalysis. The performed investigation are discussed for the reason of an possible improvement of thermal and structural properties of the alloy. Practical implications: The investigated material can find its use in the foundry industry; an improvement of component quality depends mainly on better control over the production parameters. Originality/value: This work provides better understanding of the thermal characteristics and processes occurred in the new developed alloy. The achieved results can be used for liquid metal processing in science and industry and obtaining of a required alloy microstructure and properties influenced by a proper production condition.
8
Content available remote Cooling rate influence on microstructure of the Zn-Al cast alloy
EN
Purpose: In this work was presented the cooling rate influence on microstructure of the Zn-Al cast alloy. This research work presents also the investigation results of derivative thermoanalysis performed using the UMSA device. The material used for investigation was the ZnAl4Cu1 alloy. Design/methodology/approach: Moreover the analysis of cooling rate influence on the derivative curve changes was performed as a result of the measured crystallisation kinetic changes. For the assessment of the cooling rate influence on the mechanical properties also hardness measurements were performed using the Rockwell hardness device. Findings: The treated sample is without holes, cracks and defects as well as has a slightly higher hardness value compared to the as-cast material. Research limitations/implications: The material was examined metallographically and analyzed qualitatively using light and scanning electron microscope as well as the area mapping and point-wise EDS microanalysis. The performed investigation are discussed for the reason of an possible improvement of thermal and structural properties of the alloy. Practical implications: The investigated material can find its use in the foundry industry; an improvement of component quality depends mainly on better control over the production parameters. Originality/value: This work provides better understanding of the thermal characteristics and processes occurred in the new developed alloy. The achieved results can be used for liquid metal processing in science and industry and obtaining of a required alloy microstructure and properties influenced by a proper production conditions.
EN
Purpose: This paper contains description made on thermovision testing with the use of Inframetrics 760B system. Measurements were executed on the surface of a heat furnace and also on the surface of material heated before and hot-rolled. The results of the investigations in a form of thermograpic pictures were taken down in working environment. Design/methodology/approach: The purpose of this research was to evaluate technological process of heating cooper and brass cakes, and hot-rolled strip in special passes assessment of the temperature modification. For basic criterion estimation of these processes, the maintenance at the demanded final rolling temperature in order to keep up adequate structure and narrow range of mechanical properties variation was accepted. Findings: The process of heating charge material is carried through in order to facilitate its machining in a rolling process. When the material does not obtain the adequate temperature or does not become uniformly heated, internal stresses which cause appearance of the rims of fracture and occurrence of other defects in structure appear in cold rolling, as the next. Because of this there is a need of temperature controlling. Research limitations/implications: If a temperature profile on heated to a hot-rolled cakes is not uniform and does not reach a given level, this can mean forming some defects, which can be revealed during a hot-rolled process, relatively during following technological operations leading to a quality decrease and in a consequence to product disqualification Originality/value: The use of thermovision system in processes of heating cakes evolution and also hot-rolling. These research enable a condition control of thermal furnace and hot-roll processes.
10
Content available remote Computer-assisted the optimisation of technological process
EN
Purpose: One has worked out an application that allows to analyze the efficiency of technological process in aspect of nonmaterial values and has used neural networks to verify particle indicators of quality of a process operation. Indicators appointment makes it possible to evaluate the process efficiency, which can constitute an optimization basis of particular operation. Design/methodology/ approach: The created model made it possible to analyze the chosen technological processes for the sake of efficiency criteria, which describe the relationships: operation - material, operation - machine, operation - man, operation - technological parameters. Findings: In order to automate the process, to determine the efficiency of technological operation (KiX) and possibly to optimize it, one has applied one of artificial intelligence tools - neural networks. Practical implications: Application of neural networks allows to determine the value of technological efficiency of an operation. (KiX) without the necessity of detailed analysis as well of the whole process as of the particular operation. It makes it also possible to optimize operation efficiency by means of checking value of operation efficiency in the case of change in value of particular partial efficiency indicators. Originality/value: Method of computer application makes it possible to point out the studied indicators and asses finally the process efficiency in order to plan optimization of particular operation.
12
Content available remote Structure analysis of Al cast alloy
EN
Purpose: The developed design methodologies both the material and technological ones will make it possible to improve shortly the quality of materials from the light alloys in the technological process, and the automatic process flow correction will make the production cost reduction possible, and - first of all-to reduce the amount of the waste products. Design/methodology/approach: Castings were analysed in the paper of car engine blocks and heads from the Al-Si-Cu alloys of the AC-AlSi7Cu3Mg type fabricated with the "Cosworth" technological process. In this work the AC-AlSi7Cu3Mg alloy structure was investigated, of this alloy samples were cut of for structure analysis of the cylinder part as well of crankshaft of a fuel engine. The investigation show a difference in the (phase) structure morphology as a result of cast cooling rate. Findings: On the quality of casting has influence the walls thickness of car engine elements. Practical implications: In the metal casting industry, an improvement of component quality depends mainly on better control over the production parameters. Originality/value: The value of the applied methodology was to correct identify the casting effects that occurred during the casting process.
13
Content available remote Analysis of technological process on the basis of nonmaterials values
EN
Purpose: What determines the correcttness of industrial company's functiioning on the market is technological process. In order to improve it continuously the priority should be technology, technology management and controlling. Design/methodology/approach: by means of this model one can analyzy the choosen technological processes for the sake of efficiency criteria. They describe following relationships: operation-material, operation-machine, operation-man, operation-technological parameters. Findings: This analisis shows hypothetical technological processes on production of typical pieces for machines. One has also taken into account nonmaterials parameters of technological process. They are resulting from applied sampels and projecting of the technological process. Practical implications: Thanks to the created aplication we can analyze efficiency of technological process in aspect of nonmaterial values. By the use of neural networks we can verify particle indicators of process operation quality, evaluate the process efficiency, which can constitute the optimization basis of particular operation. Originality/value: Data effecting from this analisis allowed to optimize the technological process. They estimate influence of the analyzed parameters on the whole process and optimizethe conducting of any process.
EN
The experiments conducted are focused on natural organic substances, removal from water in ion-exchange process, ultrafiltration process and ion exchange-ultrafiltration integrated process. The water from the Odra River and model solution were investigated. In treatment processes, various doses of 5 anion-exchange resins as well as polyethersulphone membranes with different cut-offs were used. The efficiency of process was determined by measuring a decrease both in the colour intensity and the UV 254 nm absorbance. The results show that separation efficiency in integrated process depends on resin dose added to water before ultrafiltration and on the membrane cut-off as well. Among the resins tested the most efficient was MIEX ® resin. The ion-exchange process carried out prior to the ultrafiltration increased, especially for high cut-off membranes, NOM retention and resulted in the decrease of membrane fouling intensity.
PL
Usuwano naturalne substancje organiczne z wody w procesach: wymiany jonowej, ultrafiltracji i zintegrowanego procesu wymiany jonowej-ultrafiltracji. Do badań użyto wodę z Odry i roztwór modelowy będący mieszaniną wody wodociągowej i wody z torfowiska. Badania przeprowadzono dla 5 typów żywic jonowymiennych. Testy ultrafiltracji wykonano, używając membran z polietersulfonu 0 cut-off 5, 10 i 30 kDa. Skuteczność procesu określano, mierząc zmniejszanie się intensywności barwy i absorbancji UV 254 nm. Otrzymane wyniki pokazały, że dla membran o cut-off 30 kDa ultrafiltracja poprzedzona wymianą jonową zwiększa skuteczność usuwania naturalnych substancji organicznych oraz ogranicza intensywność blokowania membran. Spośród testowanych żywic najskuteczniejsza zarówno w procesie samodzielnym, jak i w układzie zintegrowanym była makroporowata żywica MIEX®.
15
Content available remote The automation of analysis of technological process effectiveness
EN
Purpose: Improvement of technological processes by the use of technological efficiency analysis can create basis of their optimization. Informatization and computerization of wider and wider scope of activity is one of the most important current development trends of an enterprise. Design/methodology/approach: Indicators appointment makes it possible to evaluate the process efficiency, which can constitute an optimization basis of particular operation. Model of technological efficiency analysis is based on particular efficiency indicators that characterize operation, taking into account following criteria: operation - material, operation - machine, operation - human, operation - technological parameters. Findings: From the qualitative and correctness of choose of technology point of view comprehensive technological processes assessment makes up the basis of technological efficiency analysis. Results of technological efficiency analysis of technological process of prove that the chosen model of technological efficiency analysis makes it possible to improve the process continuously by the technological analysis, and application of computer assistance makes it possible to automate the process of efficiency analysis, and finally controlled improvement of technological processes. Practical implications: For the sake of complexity of technological efficiency analysis one has created an AEPT computer analysis from which result: operation efficiency indicators with distinguished indicators with minimal acceptable values, values of efficiency of the applied samples, value of technological process efficiency. Originality/value: The created computer analysis of the technological process efficiency (AEPT) makes it possible to automate the process of analysis and optimization.
16
Content available remote Computer assistance in the technological process efficiency analysis
EN
Purpose: Technological process is a basic determinant of correctness of industrial company's functioning on the market. In this connection they should treat with the priority all activities connected with technology, technology management and controlling, that is with their continuous improvement. Design/methodology/approach: The created model made it possible to analyze the chosen technological processes for the sake of efficiency criteria, which describe the relationships: operation - material, operation - machine, operation - man, operation - technological parameters. Findings: in this thesis - conducted analysis includes hypothetical technological processes of producing typical machine pieces. Within their scope also the nonmaterial parameters of technological process have been taken into account, which resulted from arts of applied samples and projecting of the technological process. Practical implications: One has worked out an application that allows to analyze the efficiency of technological process in aspect of nonmaterial values and has used neural nets to verify particle indicators of quality of a process operation. Indicators appointment makes it possible to evaluate the process efficiency, which can constitute an optimization basis of particular operation. Originality/value: As a result of this analysis gained data enabled to optimize the technological process by estimating influence of the analyzed parameters on the whole of process and optimization conducting of any process.
PL
W pracy przedstawiono pomiar czynnika kształtu i współczynnika oporu cząstek nieizometrycznych takich jak zrębki wierzby energetycznej. W celu wyznaczenia powyższych parametrów zaprojektowano i zbudowano aparat, w którym dane eksperymentalne otrzymano metodą aerodynamiczną. Uzyskano eksperymentalne zależności pomiędzy współczynnikiem oporu a liczbą Reynoldsa dla wszystkich badanych zrębków i uzyskano uśrednioną wartość sferyczności dla badanej mieszanki. Dla wszystkich badanych frakcji mieści się ona w zakresie 0.612-0.676.
EN
The paper presents the results of experimental determination of the shape factor and drag coefficient of non-isometric particles like wood chips. In order to determine these parameters a specially constructed set-up was built. The experimental relationship between the drag coefficient and the Reynolds number for wood chips investigated was obtained altogether with the mean value of sphericity equals to 0.612-0.676.
18
EN
Purpose: Technological process is a basic determinant of correctness of industrial company’s functioning on the market. In this connection they should treat with the priority all activities connected with technology, technology management and controlling, that is with their continuous improvement. Design/methodology/approach: The basis for preparing the process analysis model are the indicators of fragmentary and technological efficiency, as well as standardized parameters of the technological process depending on the applied treatment. Findings: Thanks to the appropriate indicators it is possible to identify operations which need to be verified. Although interdisciplinary process control is very complex, it offers objective assessment. The assessment should include the influence of individual parameters on the process and enable good choice of the optimisation type. Practical implications: The process analysis with the use of immaterial parameters based on different types of processing and the design of the technological process involved assessment of technological process efficiency with the use of indicators of operational efficiency. Originality/value: Creating computer applications for calculating individual indicators, as well as final efficiency assessment used for planning optimisation of individual operations.
EN
Purpose: The paper presents an attempt of improving a productivity of the sleeve’s technological process by optimization times of machining operations. Design/methodology/approach: The optimization of times of turning operations was done by using the analytic and graphic method, which belongs to the linear programming. Findings: The optimization of times of turning operations by using the methods of linear programming caused shortening the total manufacturing time of a sleeve by 2%. The changes of times permitted on enlargement the volume of produced lots, what guarantees the growth of production about 5%. The calculated volume of optimum productive lot allows enlargement of the level of total productivity of studied process from 95 to 99%. Research limitations/implications: The methods of optimization such as linear programming depend on degree of complexity of physical and technical relations of the analysed machining processes. Practical implications: The work is an example of an analysis of chosen technological process in aspect of its productivity. It could be helpful to improve a level of total productivity of technological processes by using simple methods of linear programming. Originality/value: The paper presents some results of optimization of machining operations of the sleeve’s technological process, which caused enlargement of the volume of produced fabrications and growth of the level of total productivity.
20
Content available remote Analysis of technological process on the basis of efficiency criterion
EN
Purpose: Technological process is a basic determinant of correctness of industrial company’s functioning on the market. In this connection they should treat with the priority all activities connected with technology, technology management and controlling, that is with their continuous improvement. Design/methodology/approach: The created model made it possible to analyze the chosen technological processes for the sake of efficiency criteria, which describe the relationships: operation – material, operation – machine, operation – man, operation – technological parameters. Findings The in this thesis conducted analysis includes hypothetical technological processes of producing typical machine pieces. Within their scope also the nonmaterial parameters of technological process have been taken into account, which resulted from arts of applied samples and projecting of the technological process. Practical implications: One has worked out an application that allows to analyze the efficiency of technological process in aspect of nonmaterial values and has used neuronal nets to verify particle indicators of quality of a process operation. Indicators appointment makes it possible to evaluate the process efficiency, which can constitute an optimization basis of particular operation. Originality/value: As a result of this analysis gained data enabled to optimize the technological process by estimating influence of the analyzed parameters on the whole of process and optimization conducting of any process.
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