The article presents an analysis of the implementation of a selected element of the traveler safety system used in road transport. The results of metallographic tests were presented, and the state of stress introduced to the casting by means of forming the element by means of plastic forming was analyzed. An analysis of the manufacturing process was carried out indicating the risks that may lead to cracks in the material structure. Possible causes of founding defects were pointed out and possible technological solutions were pointed out in order to avoid them.
PL
W artykule przedstawiono analizę wykonania wybranego elementu wyposażenia systemu bezpieczeństwa podróżnych, stosowanego w transporcie samochodowym. Przedstawiono wyniki badań metalograficznych oraz dokonano analizy stanu naprężeń wprowadzanych do odlewu poprzez kształtowanie elementu metodą obróbki plastycznej. Dokonano analizy procesu wytwarzania wskazując na zagrożenia, które mogą prowadzić do powstawania pęknięć w strukturze materiału. Wskazano na możliwe przyczyny powstawania wad odlewniczych oraz wskazano możliwe rozwiązania technologiczne w celu ich uniknięcia.
The paper describes modification to Fm3 ̅m (space group no. 225) lattice of aluminium based α-solid solution observed in Zn-Al alloys required to properly correlate quantitative data from X-ray diffraction analysis with results obtained from quantitative scanning electron microscopy image analysis and those predicted from Zn-Al binary phase diagram. Results suggests that 14 at.% of Zn as a solute atom should be introduced in crystal lattice of aluminium to obtain correct estimation of phase quantities determined by quantitative X-ray diffraction analysis. It was shown that this modification holds for Cu mould cast as well as annealed and water-cooled samples of Zn-3wt.%. Al and Zn-5wt.% Al.
Zn-Al-Cu alloys are characterised by very good tribological properties: high resistances to abrasive wear and adhesive wear, resistance to dry friction, low friction coefficient. Important disadvantages of Zn-Al alloys include, among others low structural and dimensional instability in as-cast stage and during long-period after pouring into moulds. Studies carried out in recent years confirm the problem of dimensional instability of Zn-Al-Cu alloys may be reduced by replace copper partially with titanium. The goal of the studies carried out was to define the influence of heat treatment on the microstructure and phase composition of ZnAl40Cu(1-2)Ti(1-2) alloys. The scope of the investigations included analysis of the phase composition, tests using a scanning electron microscope and a scanning transmission electron microscope, and X-ray microanalysis. The studies carried out indicate a presence of the e-CuZn5 and Ti2ZnAl5, AlxCuyTiz phases in the ZnAl40Cu(1-2)Ti(1-2) alloys.
The aim of this paper was to determine the effect of heat treatment for the corrosion resistance of the ZnAl40Ti2Cu alloy under “acid rain” conditions. ZnAl40TiCu alloy after supersaturation and after supersaturation and aging was studied. Potentiodynamic studies, potentiostatic studies and studies on structure of the alloy top layer of samples after corrosion tests were carried out. These investigations indicated a significant influence of heat treatment on corrosion resistance of the ZnAl40Ti2Cu alloy. The highest increase in corrosion resistance comparing to the alloy in the as-cast condition may be obtained by supersaturation. A significant influence of the aging temperature and time on corrosion resistance was proved.
The main goal of the presented work was to determine the relationship between changes in the shape of the derivative curve and the microstructure of Zn-Al-Cu alloys before and after modification. To describe the phenomena that occur in the material during solidification as a result of the modification in the chemical composition, the thermal-derivative analysis method was applied. This method allows to describe and interpret the kinetics of crystallisation of the tested alloys. To describe the morph ology and phase composition, light and electron microscopy (SEM, TEM) was also used. The modification of the hypereutectic Zn-Al-Cu alloys with the addition of Ce causes a reduction in the size α' + η eutectics and change in the morphology of the α' phase precipitates from dendritic to “tweed”.
The paper is devoted to examinations of the refining efficiency of fluxes and refiners applied during melting of zinc and zinc-aluminium alloys. The content of gases, mainly hydrogen, in the alloys not protected during the charge melting and in the ones protected with the fluxes and/or refined is discussed. The performed examinations show that using the protecting fluxes and melt-refining before pouring leads to significant improvement of ductility in Zn and binary Zn-Al alloys as well as significant increase of the material clearness confirmed by increased density. Furthermore, the metallurgical yields are also increased.
PL
Praca poświęcona jest badaniom rafinacyjnej skuteczności żużli ochronnych i rafinatorów stosowanych w technologii przetapiania cynku oraz stopów cynk-aluminium. Wykonane badania wykazały, iż Zn i stopy podwójne Zn-Al przetapiane pod żużlami ochronnymi oraz przerafinowane przed odlaniem do formy wykazują zwiększoną plastyczność i zwiększoną czystość, potwierdzoną podwyższoną gęstością masy. Dodatkowo, wzrastają uzyski metalurgiczne.
7
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
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.
8
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
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.
9
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
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.
10
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
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.
11
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
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.
12
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
W artykule przedstawiono wyniki badań procesów krystalizacji stopów: aluminium – (AK9, AK65, AK132), miedzi – (MO5, B555) i cynku – Z41. Przebieg procesów krystalizacji zarejestrowano w postaci zapisu graficznego krzywych termicznych t = f(τ) i przewodności elektrycznej σ = f(τ) oraz ich pierwszych pochodnych. Opracowane programy komputerowe pozwalają określić – w charakterystycznych punktach (pikach) – na krzywych krystalizacji powstające fazy tworzące strukturę odlewu. Przeprowadzona analiza wartości liczbowych – zaznaczonych kursorami – umożliwia określenie stopnia uszlachetnienia badanych stopów.
EN
The paper presents the result of research on processes of crystallisation of alloys: aluminium – AK9, AK64, AK132; copper – MO59, B555 and zinc – Z41. The processes of crystallisation ware registered in graphical notation of thermal curves – t=f(τ) and electrical conductivity - σ = f(τ) as well as their first derivatives. Developed computer programs enable to determine – in characteristic points (peaks) of crystallisation curves – the phases building the structure of the cast. The carried out analysis of numerical values – marked with cursors – enables to determine the degree of purification of alloys.
13
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
W artykule przedstawiono wyniki badań krzepnięcia odlewów ze stopów AlSi8,6 i ZnA13,9 na podstawie analizy wykresów czasowych sumy zdarzeń emisji akustycznej. Z porównania wykre-sów czasowych sumy zdarzeń emisji akustycznej i krzywych stygnięcia wynika, że obserwacja emisji akustycznej pozwala określić koniec krzepnięcia badanego obszaru. Temperatura początkowa kokili i hamowanie skurcz liniowego w odlewie mają wpływ na wartość sumy zdarzeń emisji akustycznej, przy czym intensywność wpływu hamowania skurczu linowego jest większa w odlewach ze stopu AlSi8,6 niż ZnA13,9.
EN
The paper presents the results of investigation of time runs of sum of events of acoustics emission and cooling curves in solidification process of AlSi8,6 and ZnA13,9 alloys castings. Comparison the cooling curves and time runs of acoustics emission sums of events follows that it is possible to determine the end of solidification using the acoustics emission in studied domain. The initial temperature of permanent mould has the influence on the value of sums of events of acoustics emission. Hindering of linear shrinkage in castings has high influence on the value of sums of events of acoustics emission, the volume of that influence is higher in castings made of A1Si8.6 than ZnA13,9.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.