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1
Content available remote Metoda hybrydowa jako innowacyjne rozwiązanie nanoszenia powłok ochronnych
PL
W opracowaniu przedstawiono innowacyjną metodę hybrydową (HM – hybrid method) jako modyfikację procesu natryskiwania z naddźwiękową strugą materiału powłokowego, którą stworzono w celu ograniczenia sumarycznych kosztów natryskiwania ujmujących aspekty czasu wykonania powłoki oraz zużycia materiałów i energii w procesie wykonania powłoki. Metoda ta umożliwia wytworzenie powłok ochronnych o właściwościach eksploatacyjnych zbliżonych do uzyskiwanych klasyczną metodą HVOF. Zaprezentowano wyniki badań odporności na utlenianie powłok wytworzonych metodą HM przeprowadzone w warunkach laboratoryjnych. Prezentowany test korozyjny miał charakter cykliczny. Przeprowadzono go w temperaturze 650oC i czasie 500 godzin. Przedstawiono wybrane wyniki badań strukturalnych produktów korozji tworzących się na powłokach w trakcie trwania testu. Na wysoką odporność korozyjną badanych materiałów ma wpływ zarówno ich skład chemiczny i fazowy jak i otrzymana zwarta struktura powłoki. Wyniki badań wskazują, że dobrane parametry procesu innowacyjnego procesu natryskiwania są właściwe i potwierdzają jej możliwości w zakresie wytworzenia zwartej, gęstej powłoki o znacznej odporności korozyjnej.
EN
The paper presents an innovative hybrid method (HM) as a modification of the supersonic spraying process of coating material, that was designed to limit the total spraying costs of the coating including material and energy consumption in the spraying process. This method makes it possible to produce protective coatings with similar operating characteristics to the classic HVOF method. In the paper the results of the oxidation resistance of HM coatings were presented. The presented oxidation test was carried out in laboratory conditions. The test was cyclical. It was run at 650oC and 500 hours. The results of structural studies on corrosion products formed on the coatings during the test are presented. The high resistance of the tested materials is determined by their chemical and phase composition and the obtained compact structure of coating. The results show, that the chosen parameters of spraying in the innovative method are correct and the results confirm its ability to produce a compact, density coatings with significant corrosion resistance.
EN
Weld metal deposit (WMD) was carried out for standard MMA welding process. This welding method is still promising mainly due to the high amount of AF (acicular ferrite) and low amount of MAC (self-tempered martensite, retained austenite, carbide) phases in WMD. That structure corresponds with good impact toughness of welds at low temperature. Separate effect of these elements on the mechanical properties of welds is well known, but the combined effect of these alloy additions has not been analyzed so far. It was decided to check the total influence of nickel with a content between 1% to 3% and molybdenum with content from 0.1% up to 0.5%.
EN
The paper offers mathematical equations of the influence of micro-jet cooling on structure and impact toughness properties of metal weld deposit. Weld metal deposit (WMD) was carried out for standard MIG welding and for MIG welding with micro-jet cooling. This new method is very promising mainly due to the high amount of AF (acicular ferrite) and low amount of MAC (selftempered martensite, retained austenite, carbide) phases in WMD. That structure corresponds with very good mechanical properties ie. good impact toughness of welds at low temperature. Micro-jet cooling after welding can find serious application in automotive industry very soon. Until that moment only argon, helium, nitrogen and gas mixtures of argon were tested for micro-jet cooling after welding. The best results of mechanical properties of WMD in presented welding method correspond with micro-jet argon cooling.
EN
The aim of this paper is to analyse the mechanical properties of the weld steel structure of car body truck frames after laser welding. The best welding conditions involve the use of proper materials and alloy elements in steel and filer materials, in addition to welding technology, state of stress and temperature of exploitation. We present for the first time the properties of steel track structures after laser welding with micro-jet cooling. Therefore, good selection of both welding parameters and micro-jet cooling parameters is very important to achieve a proper steel structure. In this study, the metallographic structure, tensile results and impact toughness of welded joints have been analysed in terms of welding parameters.
EN
Thermally spraying with micro-jet cooling is an innovate technology. It is possible to get fine dispersive structure of coatings during the shorter time in comparable to the classical high velocity oxygen fuel process (HVOF). It corresponds with good corrosion-erosion properties of structure. In the paper the parameters of the spraying with micro-jet cooling process are presented. The selected properties of coatings obtained by hybrid method are presented. The results of wear tests for hybrid and HVOF coating are compared. Results of investigation are very optimistic. The presented technology should be adapted to the actual production of protective coating for machines and construction working in wear conditions.
EN
The paper focuses on low alloy steel after innovate welding method with micro-jet cooling. Weld metal deposit (WMD) was carried out for welding and for MIG and MAG welding with micro-jet cooling. This method is very promising mainly due to the high amount of AF (acicular ferrite) and low amount of MAC (self-tempered martensite, retained austenite, carbide) phases in WMD. That structure corresponds with very good mechanical properties, ie. high impact toughness of welds at low temperature. Micro-jet cooling after welding can find serious application in automotive industry very soon. Until that moment only argon, helium and nitrogen were tested as micro-jet gases. In that paper first time various gas mixtures (gas mixtures Ar-CO2) were tested for micro-jet cooling after welding.
EN
The article presents results of investigations on autogenous laser welding of new grade STRENX 1100 MC steel. The modern Disk laser was applied for of 5.0 mm thick butt joints welding. The influence of laser welding parameters, mainly the energy input of laser welding on the penetration shape, weld quality, structure and mechanical performance was investigated. It was found that the investigated steel has surprisingly low carbon equivalent CET just 0.328, and also relatively high temperature of martensitic transformation Ms at 430.6°C. Despite very rapid cooling times t8/5 in a range from 0.6 to 1.3 s, thus rapid solidification there was no tendency to cracking of weld metal or HAZ. Significant drop of microhardness in the HAZ resulted in a decrease of tensile strength of joints, compared to the base metal. Impact toughness of test joints was at only 50÷60% of the base metal.
8
Content available Impact Toughness of Steel WMD after TIG Welding
EN
The material selected for this investigation was low alloy weld metal deposit after TIG welding with various amount of oxygen in weld metal deposit (WMD). After TIG process it is difficult to get proper amount of oxygen in WMD on the level much lower than 350 ppm. The highest impact toughness of low alloy WMD corresponds with the amount of oxygen in WMD above 350 ppm. In the paper focuses on low alloy steel after innovate welding method with micro-jet cooling that could be treated as a chance on rising amount of oxygen in weld. Weld metal deposit (WMD) was carried out for TIG welding with micro-jet cooling with various amount of oxygen in WMD. In that paper various gas mixtures (gas mixtures Ar-O2 and Ar-CO2) were tested for micro-jet cooling after TIG welding. An important role in the interpretation of the results can give methods of artificial intelligence.
EN
The goal of this paper is to analyze the exploitation and safety conditions of weld steel structure of car body truck frames after welding repairs made by covered electrodes. The main role of conditions in connected with materials, alloy elements in steel and filer materials, welding technology, state of stress and temperature. Because of that, good selection of steel and choice of welding method for proper steel structure repairs are very important. For responsible steel, structures like truck frames and low alloy steel are used, very often with small amounts of carbon and some amounts of alloy elements such as Ni and Mo in low alloy steel and their welds. To study the frame’s flexibility and resistance, welded joints have been analyzed. Samples have been welded by steel electrodes with various amounts of Ni.
PL
Celem artykułu jest analiza właściwości eksploatacyjnych oraz bezpieczeństwa naprawianych ram pojazdów ciężarowych z użyciem spawania. Ważną rolę odgrywają połączenia materiałów, pierwiastki stopowe, materiały dodatkowe, technologia spawania, stan naprężeń oraz temperatura. Bardzo istotne są odpowiedni dobór stali oraz metody spawalniczej. Na odpowiedzialne konstrukcje stalowe, jak np. ramy pojazdów ciężarowych, jest używana niskostopowa stal, często z niską zawartością węgla oraz dodatkiem pierwiastków stopowych, takich jak Ni oraz Mo. Do oceny elastyczności oraz wytrzymałości połączeń spawanych w ramach pojazdów ciężarowych, analizowano właściwości połączeń wykonanych elektrodami o różnej zawartości Ni.
EN
This paper presents results of experimental research concerning the impact of an innovative method of micro-jet cooling on the padding weld performed with MAG welding. It enables to steer the parameters of weld cooling in a precise manner. Micro-jet cooling is a novel method patented in 2011. In addition, various elements, which may e.g. enhance hardness or alter tribological properties, can be entered into its top surface, depending on the applied cooling gas. The micro-jet welding method is the innovative method, which reduces the intensity of abrasive wear. The method can be used as a basic finishing or a regeneration method. An innovative technology for micro-jet is used to cool the weld surface that is, using a micro-welding jet cooling. This allows accurate and complete control of the surface structure of the deposit. The material under study was steel 16MnCr5, which was subject to the welding process with different gases of micro-jet cooling. Nitrogen and air was used as a cooling gas. The main parameter of weld assessment was wear intensity. The tests were conducted in a tribological pin-on-disc type position. T-11 pin-on-disc tester allows for indicating basic wear parameters (wear intensity, wear coefficient, wear force). Based on results of experiment the application of nitrogen in micro-jet cooling of the padding weld in the welding process of steel 16MnCr5 beneficially affects resistance to abrasive wear.
EN
In order to improve the tribological properties of titanium alloy Ti6Al4V composite surface layers Ti/TiN were produced during laser surface gas nitriding by means of a novel high power direct diode laser with unique characteristics of the laser beam and a rectangular beam spot. Microstructure, surface topography and microhardness distribution across the surface layers were analyzed. Ball-on-disk tests were performed to evaluate and compare the wear and friction characteristics of surface layers nitrided at different process parameters, base metal of titanium alloy Ti6Al4V and also the commercially pure titanium. Results showed that under dry sliding condition the commercially pure titanium samples have the highest coefficient of friction about 0.45, compared to 0.36 of titanium alloy Ti6Al4V and 0.1-0.13 in a case of the laser gas nitrided surface layers. The volume loss of Ti6Al4V samples under such conditions is twice lower than in a case of pure titanium. On the other hand the composite surface layer characterized by the highest wear resistance showed almost 21 times lower volume loss during the ball-on-disk test, compared to Ti6Al4V samples.
EN
The material selected for this investigation was low alloy steel weld metal deposit (WMD) after MIG welding with micro-jet cooling. The present investigation w*as aimed as the following tasks: obtained WMD with various amount of acicular ferrite and further analyze impact toughness of WMD in terms of acicular ferrite amount in it. Weld metal deposit (WMD) was first time carried out for MIG welding with micro-jet cooling of compressed air and gas mixture of argon and air. Until that moment only argon, helium and nitrogen were tested as micro-jet gases for MIG/MAG processes. An important role in the interpretation of the results can give methods of artificial intelligence.
EN
The innovative technology, like thermal spraying with a micro-jet cooling is one of the important modification of classical ultrasonic spraying methods. Using of micro-stream with gases like argon or nitrogen allows to cool the coating immediately after spraying, and thereby reduce the time of transition during the injection of each layer. As a result of the process, the fine dispersive structure of coatings is obtained during the shorter time in comparable to the classical high velocity oxygen fuel process (HVOF). The parameter of process and the type of stream equipment determine the quality of the obtained structure and thermal stress in the coating. The article presents the relationship between selected parameters of hybrid process and properties of the coatings. The presented technology should be adapted to the actual production of protective coating for machines and construction working in wear conditions.
EN
The paper provides a comprehensive presentation of the influence of operating parameters on the tribological properties of the wheel-rail couple. Apart from wear and a friction coefficient, the tribological properties also comprise stereological parameters of flaky wear products. The tribological tests were carried out according to an experimental plan, which took account of the complex influence of operational factors on the size and shape of flaky wear products. This enabled defining the type and intensity of wear, depending on the variable operational parameters. In order to explain the wear mechanism, quantitative, qualitative, and profilographometric metallographic examinations were made.
EN
Low carbon steel weld structures generally exhibit a very linear stress-strain relationship. In the study of strength of materials, the compressive strength is the capacity of a material or structure to withstand loads tending to reduce size of structure. It is mainly measured by plotting applied force against deformation in a testing machine. Compressive strength is a main key value for design of welded structures.The main goal of that paper was analysing of plastic properties of frame welds which were made with various parameters of micro-jet cooling. New technology of micro-jet welding could be regarded as a new way to improve plastic properties of welds. It allows to obtain welds with better mechanical properties in comparison to ordinary welding method. Furthermore it is possible to steering of weld structure and properties of the weld. There were given main information about influence of various micro-jet gases on metallographic and properties of structure steel welds.
EN
This paper presents results of experimental research concerning the impact of an innovative method of micro-jet cooling on the padding weld performed with MIG welding. Micro-jet cooling is a novel method patented in 2011. It enables to steer the parameters of weld cooling in a precise manner. In addition, various elements which may e.g. enhance hardness or alter tribological properties can be entered into its top surface, depending on the applied cooling gas. The material under study was steel 20MnCr5, which was subject to the welding process with micro-jet cooling and without cooling. Nitrogen was used as a cooling gas. The main parameter of weld assessment was wear intensity. The tests were conducted in a tribological pin-on-disc type position. The following results exhibit growth at approximately 5% in wear resistance of padding welds with micro-jet cooling.
17
EN
The material selected for this investigation was low alloy steel weld metal deposit (WMD) after MAG welding with micro-jet cooling. The present investigation was aimed as the following tasks: analyze impact toughness of WMD in terms of micro-jet cooling parameters. Weld metal deposit (WMD) was first time carried out for MAG welding with micro-jet cooling of compressed air and gas mixture of argon and air. Until that moment only argon, helium and nitrogen and its gas mixture were tested for micro-jet cooling.
EN
The paper presents thermal images of an elbow joint area after it was loaded with three series of 40 push ups. The rises in the skin surface temperature were analysed, and measurement points on four sides of the joint were selected. The temperature rises were determined along with the reasons why they occurred in these points. Then the heat and mass transfer model was described, and the energy balance of the heat given off by the skin surface was made.
PL
Przedstawiono obrazy termowizyjne powierzchni łokcia po tym, jak został obciążony trzema seriami 40 pompek. Wybrano punkty pomiarowe dla czterech stron stawu łokciowego i przeanalizowano w nich wzrosty temperatury powierzchni skóry. Wzrosty temperatury wyznaczono wraz z uzasadnieniem, dlaczego wystąpiły w tych punktach. Następnie opisano model wymiany ciepła i masy oraz wykonano bilans energii ciepła oddawanego przez powierzchnię skóry.
19
Content available Badania termowizyjne obciążonego stawu biodrowego
PL
W artykule przedstawiono wyniki badań obciążonego stawu biodrowego. Staw biodrowy obciążano cyklami ćwiczeń gimnastycznych. Temperaturę w okolicach stawu monitorowano przy użyciu kamery termowizyjnej. Określono zmiany temperatury powierzchni skóry w wybranych miejscach.
EN
The article presents the results of the load of the hip. The hip joint is loaded cycle exercise. The temperature in the vicinity of the joint were monitored using a thermal imaging camera. Changes of skin surface temperature at selected locations are analyzed.
EN
The paper presents results of research tribological properties laser hardened steel 42CrMo4. Parameter influencing on the quality of the hardened surface was laser head speed. The study was conducted on friction tester pin-on-disc type T-11, and a counter sample disc was silicate. Parameter determining the quality of the surface layer is the intensity of wear. Based on the results we obtain information about the laser head speed to temper steel 42CrMo4 so as to maintain a high resistance to wear.
PL
W pracy przedstawiono wyniki badań właściwości tribologicznych stali 42CrMo4 poddanej hartowaniu laserowemu. Parametrem wpływającym na jakość hartowanej powierzchni była prędkości głowicy lasera. Badania tarciowe przeprowadzono na testerze typu trzpień-tarcza T-11, a przeciwpróbkę stanowiła tarcza silikatowa. Parametrem wyznaczającym jakość uzyskanej warstwy była intensywność zużycia. Na podstawie wyników badań uzyskujemy informację, z jaką prędkością głowicy możemy hartować stal 42CrMo4 tak aby zachować wysoką odporność na zużycie ścierne.
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