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1
Content available remote Gazy osłonowe do spawania tytanu, cyrkonu i ich stopów
PL
W artykule mówiono rodzaj i skład gazów używanych podczas spawania tytanu, cyrkonu i ich stopów, jak również opisano wpływ poszczególnych gazów na proces spawania i jakość złączy spawanych.
XX
The type and composition of gases used in welding of titanium, zirconium and their alloys are discussed, as well as the influence of shielding gases on welding process and quality of welded joints are described.
2
Content available remote Gazy osłonowe do spawania niklu, kobaltu i ich stopów
PL
W artykule omówiono rodzaj i skład gazów używanych podczas spawania niklu, kobaltu i ich stopów, jak również opisano wpływ poszczególnych gazów na proces spawania i jakość złączy spawanych.
EN
The type and composition of gases used in welding of nickel, cobalt and their alloys are discussed, as well as the influence of shielding gases on welding process and quality of welded joints are described.
EN
Ni55.8Ti shape memory alloys (SMAs) find applications in different fields of medical and engineering. In every field, surface integrity greatly affects the functional performance of shape memory alloy parts. In the present work, wire spark erosion machining of Ni55.8Ti shape memory alloys has been conducted and surface integrity parameters of the machined specimens have been evaluated. Experiments are designed using Taguchi L16 robust design of experiment technique. Effect of important process parameters, i.e. voltage, pulse-on time and pulse-off time on maximum surface roughness has been studied. Deterioration in surface integrity at various combinations of pulse-on and pulse-of time which produced high discharge energy has been observed. Scanned electron microscopic investigation, energy dispersive spectroscopy and XRD analyses, roughness measurement, and micro-hardness testing results are presented, analyzed and discussed. Optimization of process parameters resulted in surface integrity enhancement with low roughness (Rt – 7.78 mm and Ra – 1.45 mm) and very thin recast layer (4–6 mm) along with minimum subsurface defects.
4
Content available remote The influence of laser alloying of Ti13Nb13Zr on surface topography and properties
EN
The laser alloying is a continually developing surface treatment because of its significant and specific structuration of a surface. In particular, it is applied for Ti alloys, being now the most essential biomaterials` group for load-bearing implants. The present research was performed on the Ti13Nb13Zr alloy subject to laser modification in order to determine the treatment effects on surface topography and its some mechanical properties like nanohardness, Young's modulus, roughness. A pulse laser Nd:YAG was applied at three different laser pulse regimes: either 700 W, 1000 W or 1000 W treatment followed by 700 W modification at a pulse duration of 1 ms. The surface topography and morphology were examined using light microscopy and scanning electron microscopy with spectroscope of X-ray energy dispersion. The mechanical properties were determined by nanoindentation tests and surface roughness with a use of profilograph. The wettability was tested with a goniometer. The obtained results demonstrate complex behavior of the material surface: decrease in penetration distance and increase in hardness after first laser treatment, maintenance of this trend when machining using a higher laser pulse power, followed by an increase in penetration and decrease in hardness after additional laser treatment at lower power input, due to which a surface with fewer defects is obtained. The change in Young`s modulus follows the change in other mechanical properties, but not a change in roughness. Therefore, the observed hardening with the increase of the laser pulse power and then a small softening with the use of additional treatment with lower power can be attributed to some processes of remelting, diffusion and crystallization, sensitive to the previous surface state and heat energy flux. Despite that, the laser treatment always caused a significant hardening of the surface layer.
5
Content available remote Morphology of aluminium with nickel addition on sand casting process
EN
Purpose: This research aimed to examine the morphology, elemental changes, and phase in the aluminium cast alloys with variations in nickel addition of 1%, 2% and 3%. Design/methodology/approach: Aluminium 98% was melted in sand casting process. The sand casting process was operated at 7000C and atmospheric pressure. The addition of nickel contain of 92.19% of its element. Specimens consist of 4 pieces Al-Ni with the size of 1 x 1 x 0.5 cm for morphological testing, while for phase identification testing consist of 4 pieces Al-Ni with the size of 1 x 1 x 2 cm. The morphological testing was performed using FEI Inspect S50 Scanning Electron Microscope (SEM) and the phase characterisation was conducted using Nikon ME5 Optical Microscope. Findings: The results showed that the addition of 1% nickel in the aluminium cast product could affect the morphology in granular shape with as similar size, at 2% nickel addition also has granular shape, while at 3% of nickel addition, the morphology of Al-Ni was in elongated shape. Phase identification of Al-Ni cast alloy shows that there were Al matrix with nickel that spread in grain boundary of Al. By increasing the percentage of nickel, it shows that the nickel dominated the grain boundary of Al. These results shows that Al-Ni alloy can be produced at simple route on sand casting process. Research limitations/implications: Sand casting process with 80% silica sand, 10% bentonite, 5% water. Raw material of aluminium contains of 92-99% of purity. Nickel as addition element contain of 90-92% purity. Practical implications: The addition of nickel should be prepared wisely in term of the calculation of alloying treatment because it will effect the mechanical properties of Al alloy itself. This research can be improved by varying the temperature of casting process, variation of nickel percentage, and observation of mechanical properties of Al-Ni alloy. Originality/value: Simple route of making Al-Ni alloy using sand casting method in laboratory and also the observation of nickel addition in aluminium matrix as the result of casting product.
6
EN
Treatment of metal alloys is one of the ways to affect the properties of the material. The article describes an experiment realized at FPTM UJEP when was experimentally studied the influence of alloys AlSi9CuMnNi calcium modification on some of its properties. The alloy was modified with various amounts of calcium and subsequently machining. Also hardness was measured in the resulting alloys. Machining was performed under certain cutting conditions. After machining the obtained chip was evaluated. Chip was evaluated for its shape, length and amount of chips per 100 g. Devices in FPTM laboratories were used to prepare experimental casts and to evaluate hardness and chips, like the melting furnace LAC K70/13, hardness tester Ernst AT 250X or microscope Olympus SZX 10. Experimental quantities of calcium was 0.05, 0.1 and 0.15 wt. %. Presented experiments are part of the extensive research undertaken at Faculty of Production Technologies and Management at Jan Evangelista Purkyně University in Ústí nad Labem.
PL
W pracy omówiono podstawowe metody badawcze, wykorzystujące koncepcję pręta Hopkinsona, wykorzystywane do wyznaczania krzywych ściskania materiałów konstrukcyjnych w warunkach obciążeń udarowych. Ponadto zaprezentowano opracowane i wykonane w Instytucie Transportu Samochodowego stanowisko stosowane do badania charakterystyk mechanicznych materiałów przy dużych szybkościach odkształcania. Opisana aparatura posłużyła do wyznaczenia charakterystyk naprężenia w funkcji odkształcenia wybranych stopów. Na podstawie otrzymanych wykresów można ocenić wrażliwość badanych materiałów na szybkość odkształcania.
EN
Basic experimental methods based on the Hopkinson bar concept were discussed in this paper. The methods are used to determine compressive curves of materials under impact loading conditions. Moreover, the testing stand designed and fabricated in the Motor Transport Institute was introduced. The testing stand is used to analyse mechanical behavior of a materials at a high strain rates. Described equipment was applied to estimate stress-strain curves of selected structural materials. On the basis of the obtained characteristics strain rate sensitivity may be investigated.
EN
Microstructures of superalloys have dramatically changed throughout the years, as modern technology of its casting or forging has become more sophisticated. The first superalloys have polyedric microstructure consisting of gamma solid solution, some fraction of gamma prime and of course grain boundaries. As demands on higher performance of aero jet engine increases, the changes in superalloys micro-structure become more significant. A further step in microstructure evolution was directionally solidified alloys with columnar gamma prime particles. The latest microstructures are mostly monocrystalline, oriented in [001] direction of FCC gamma matrix. All microstructure changes bring necessity of proper preparation and evaluation of microstructure. Except for the already mentioned structures have gamma double prime and various carbides form can be seen. These structural parameters have mainly positive influence on important mechanical properties of superalloys. The paper deals with a microstructural evaluation of both groups of alloys – cast and as well as wrought. Micro-structure evaluation helps to describe mechanism at various loading and failure of progressive superalloys. Such an example where micro-structure evaluation is employed is fractography of failure surfaces after fatigue tests, which are examples of metallography evaluation de-scribed in this paper as a secondary objective.
PL
Praca dotyczy badań nad anodowym utlenianie galwanicznych powłok stopowych Zn-Ni w kąpielach alkalicznych. Stanowiły je nasycone wodne roztwory trzech wodorotlenków metali ziem alkalicznych, tj.: Ca(OH)2, Sr(OH)2 i Ba(OH)2. W ramach pracy wykonano badania struktury powierzchni anodowanych powłok Zn-Ni za pomocą elektronowej mikroskopii skaningowej (SEM) oraz ich składu chemicznego metodą spektroskopii fotoelektronów (XPS). Przeprowadzono także badania odporności korozyjnej w roztworze chlorku sodu metodą potencjodynamiczną (LSV). Na podstawie przeprowadzonych badań stwierdzono, że proces anodowego utleniania w tych roztworach prowadzi do powstawania powłok o charakterze tlenkowo-wodorotlenkowym wpływających na poprawę odporności korozyjnej.
EN
This work is connected with anodic oxidation of galvanic Zn-Ni alloy coatings in alkaline baths which were saturated hydrous solutions of three hydroxides of alkaline earth metals, i.e.: Ca(OH)2, Sr(OH)2 i Ba(OH)2. Investigation of surface structure of the anodized Zn-Ni coatings by means of scanning electron microscopy (SEM) as well as their chemical composition by X-ray photoelectron spectroscopy (XPS) have been done within the framework of the studies. The corrosion resistance studies in sodium chloride solution by potentiodynamic method (LSV) have been also made. On the basis of the obtained results it was found that the process of anodic oxidation in the solutions leads to formation of oxide and hydroxide character coatings which influence the corrosion resistance improvement.
PL
Awarie systemów spowodowane wyładowaniami atmosferycznymi, jak i przepięciami są dosyć powszechne – nowa rodzina produktów, na którą składają się kompleksowe urządzenia zabezpieczające, zapewnia skuteczną ochronę właśnie przed takimi niepożądanymi zjawiskami. Firma Phoenix Contact opracowała technologię Safe Energy Control (SEC), aby ochrona maszyn i instalacji elektrycznych przed wyładowaniami atmosferycznymi i przepięciami była jeszcze bardzie efektywna i długotrwała. W praktyce oznacza to m.in. łatwiejsze zastosowanie, w tym brak konieczności stosowania dodatkowych dobezpieczeń obwodów ograniczników.
PL
Mikrostrukturę stopu A359 i kompozytu na bazie stopu A359 zbrojonego cząsteczkami SiC poddano metalograficznej ocenie ilościowej. Przedstawiono charakterystyki mechaniczne tych materiałów wyznaczone w oparciu o oryginalną zmodyfikowaną próbę niskocyklową. Zaproponowano wielokrotny przetop jako alternatywę dla innych metod recyklingu.
EN
The microstructure of alloy A359 and A359-based composite reinforced with SiC particles was quantitatively assessed. The mechanical characteristics determined by means of the modified low cycle fatigue method on these materials were disclosed. The multiple remelting process was proposed as an alternative for the other recycling methods.
12
Content available remote Brazeability of Grade 2 titanium and AZ31B magnesium alloy under flux cover
EN
The article presents the basic issues related to brazing of poorly brazeable materials such as titanium and magnesium alloys. The text contains exemplary chemical compositions of fluxes used in brazing of poorly brazeable materials and presents the results of composition and technological process-related tests concerning fluxes used for brazing of Grade 2 titanium and AZ31B magnesium alloy. The article also presents the brazing properties of fluxes and test results concerning the mechanical properties of brazed joints as well as the results of metallographic examination utilising light and electron microscopy.
PL
Artykuł stanowi przegląd literatury oraz wyników badań eksperymentalnych na temat możliwości wykorzystania roztworów kwaśnych w procesach roztwarzania cyny ze stopów lutowniczych i odzysku tego metalu w procesie elektrolizy. Przedstawiono wyniki badań laboratoryjnych procesów anodowego roztwarzania syntetycznego stopu cyny ze srebrem, stanowiącego układ dwufazowy. W roztworach HCl stop roztwarza się nierównomiernie, przy czym jedynie cyna przechodzi do elektrolitu, a następnie wydziela się na katodzie w postaci osadu o budowie dendrytycznej. Szlam anodowy stanowi nieroztwarzalna faza Ag3Sn. Wydajność procesu anodowego wynosiła 107 ±2 %, niezależnie od warunków elektrolizy. Wydajność procesu katodowego mieściła się w zakresie 68÷91 %, przy czym malała ze wzrostem stężenia HCl i spadkiem gęstości prądu. Całkowity odzysk metalicznej cyny ze stopu wynosił 84÷89 %. Procesy katodowej redukcji jonów cyny(II) i jonów wodorowych badano metodą woltamperometrii cyklicznej.
EN
The paper contains a review of the literature and laboratory studies on the recovery of tin from solders using acid solutions and electrowinning. The results of the anodic dissolution of two-phase tin-silver alloy were discussed. The alloy dissolved selectively in HCl solutions, where only tin ions were transferred to the electrolyte and then were reduced on the cathode producing dendritic deposits. Anode slime consisted of insoluble Ag3Sn phase. Anodic current efficiency was 107 ±2 % regardless of the electrolysis conditions. Cathodic current efficiency was in the range of 68÷91 %; it decreased with both increased HCl concentration and decreased current density. Total recovery of metallic tin from the alloy was 84÷89 %. Cathodic reduction of tin(II) and hydrogen ions was also investigated using cyclic voltammetry.
PL
W pracy przedstawiono wyniki badań strukturalnych oraz magnetycznych kompozytów otrzymanych na bazie stopu o składzie chemicznym Fe67Co10Ni1W2B20 i żywicy epoksydowej. Badane próbki miały kształt walców oraz posiadały ten sam udział objętościowy żywicy epoksydowej (klej Epidian 100). Wytworzony stop o składzie chemicznym Fe67Co10Ni1W2B20 został niskoenergetycznie rozkruszony w moździerzu, a następnie poddany analizie sitowej i podzielony na trzy frakcje: 20-50 µm, 50-100 µm oraz 100-200 µm. Tak otrzymane proszki stopów zostały połączone z żywicą epoksydową. Określono wpływ wielkości cząstek proszku i osnowy na właściwości magnetyczne kompozytów.
EN
The paper presents the results of the structural and magnetic studies of composites obtained on the Basic of the alloy Fe67Co10Ni1W2B20 and epoxy resin (glue Epidian 100). The resulting alloy with chemical composition Fe67Co10Ni1W2B20 was low-energy crushed in a mortar, and then subjected to a sieve analysis and divided into three fractions: 20-50 microns, 50-100 microns and 100-200 microns. The thus obtained alloy powders were combined with an epoxy resin. Were identified: powder particle size and the magnetic properties of the matrix composites.
EN
Fe–23wt.%Mn–3wt.%Si–3wt.%Al alloy was cast, homogenized at 1150ºC, hot-rolled at temperatures between 1200ºC and 900ºC and next cold-rolled from 5% up to 40% reductions in thickness. Microstructure and texture of this alloy, which has a low stacking fault energy, were defined after cold-rolling. Investigation of transmission electron microscopy and X-ray diffraction showed that mechanical twinning and martensitic transformations (γfcc→εhcp and γfcc→εhcp→α′bcc) took place during cold-rolling. The crystallographic Shoji-Nishiyama (S-N) {00.2}ε║{111}γ, <11.0>ε ║ <110>γ and Kurdjumov-Sachs (K-S) {111}γ║{101}α’, <101>γ║<111>α’ relations between martensite (ε, α’) and austenite (γ), were found in the coldrolled material.
PL
W artykule zamieszczono wyniki badań mikrostruktury i tekstury otrzymane dla stopu Fe–23%Mn–3%Si–3%Al (% masowe). Po odlaniu wlewek homogenizowano przy temperaturze 1150ºC, walcowano na gorąco w zakresie temperatur 1200ºC-900ºC i następnie walcowano na zimno do odkształceń od 5% do 40%. Wyniki badań uzyskane przy użyciu transmisyjnej mikroskopii elektronowej i metod dyfrakcyjnych wskazują, że podczas odkształcenia plastycznego na zimno w stopie zachodzi mechaniczne bliźniakowanie i przemiana martenzytyczna. Występują zależności krystalograficzne pomiędzy austenitem (faza γ) i martenzytem (faza ε i faza α’), które opisują zależności: Shoji-Nishiyama {00.2}ε || {111}γ, <11.0>ε || <110>γ i Kurdjumowa-Sachsa {111}γ || {110}α, <110>γ || <111>α.
16
Content available Comparative characteristics of endodontic drills
EN
The work concerns the analysis of influence of the wear process of endodontic instruments on the mechanical and physico-chemical properties of the materials from which they are made. A detailed study of the microstructure, mechanical properties and corrosion resistance in the environment simulating work of the tool was conducted. The research was done for the new Mtwo endodontic files and after six times of use. In addition, the observations with a scanning electron microscope in order to reveal possible damage caused by the impact of a corrosive environment were carried out. The results showed that use of the tool by six times revealed damage at the edges of the blades and may cause a lack of continuity of the cutting line resulting in the uneven distribution of the resistive force which acts on the tool during operation.
PL
Przeprowadzono próby otrzymywania powłok kompozytowych Ni-P/SiC na stopach magnezu AZ91D. Jako warstwy pośrednie naniesiono: powłokę cynkową metodą cementacyjną oraz powłokę Ni-P w procesie autokatalitycznym. Powłoki scharakteryzowano pod względem składu i morfologii. Określono mikrotwardość poszczególnych warstw oraz przeprowadzono testy szczelności układu wielowarstwowego.
EN
Ni-P/SiC composite coatings were deposited on AZ91D magnesium alloys. Two interlayers were used: zinc was deposited by cementation, while Ni-P layer was obtained by electroless deposition. Zinc and nickel plating solutions should contain fluoride ions in order to protect the alloy against corrosion due to the formation of a sparingly soluble magnesium fluoride. Composition and morphology of the individual layers were described. The presence of SiC significantly increased the microhardness of the alloy surface, but porosity of the coatings and large potentials differences between the individual layers and the alloy substrate lead to the galvanic corrosion of magnesium.
PL
W artykule wskazano możliwość ekonomicznego konstruowania bezpiecznych w eksploatacji ścian szczelnych z wyciskanych rur kształtowych. Konstrukcja taka zmniejsza czterokrotnie liczbę spoin i wielokrotnie zmniejsza naprężenia własne. Przedstawiono liczne zalety takiego rozwiązania, zmniejszającego awaryjność kotłów.
EN
The work presents the possibility of economical construction of safe in exploitation leak tight walls that are made of extruded pipes of dedicated shape. The suggested construction process reduces the number of welds fourfold and reduces significantly residual stresses. The work presents the numerous advantages of the solution that increase the reliability of boilers.
19
Content available Machinability of modified AlSi7Mg0,3 alloy
EN
Al Alloys have an important position in the industry, mainly in the automotive and aerospace industries. One important group is silumins (Al-Si alloys). Al-Si alloys are the leading casting alloys based on aluminum. Machining of aluminum alloys is currently frequently used and it is an important area of production. This paper deals with an experiment that was conducted at the Faculty of Production Technology and Management, University of Jan Evangelista Purkyně in Ústí nad Labem, where alloy AlSi7Mg0,3 was experimented upon. Samples were made for processing from the master alloy AlSi7Mg0,3, subsequently unmodified and modified of Sr, Ca and Sb. This paper describes the evaluation of hardness, chip and tool wear in terms of how modification by Sr, Ca and Sb may affect analytical values.
EN
The effects of cycling on LaNi4.5Co0.5 hydrogen storage material oxidation (during electrode discharge) and reduction of its corrosion products (during charge process) are discussed. The time periods of the Ni and Co oxidation considerably decrease, whereas corresponding oxide phases reduction somewhat increase with electrode cycling. As a result, material corrosion rate increases with cycling with apparent tendency to settle down for final cycles.
PL
Dyskutowany jest wpływ cyklowania materiału wodorochłonnego LaNi4.5Co0.5 na jego utlenianie (podczas rozładowywania elektrody) i redukcję powstałych (podczas procesu ładowania) produktów korozji. Przedziały czasu odpowiadające utlenianiu Ni i Co maleją wyraźnie, natomiast czasy redukcji odpowiednich faz tlenkowych wzrastają w niewielkim stopniu wskutek cyrklowania elektrody. W efekcie, szybkość korozji materiału wzrasta z numerem cyklu, z pewną tendencją do ustalenia na stałym poziomie dla cykli końcowych.
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