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EN
The results of examinations of microstructure and an analysis of its impact on selected mechanical properties of austempered ductile iron (ADI) were presented in the paper. The ADI was produced from the ductile iron containing 1.56% Ni only alloying addition. The effect of the austempering time and temperature on the microstructure and mechanical properties of the examined cast iron was considered. Constant conditions of austenitizing were assumed and six variants of the austempering treatment were adopted. The studyof mechanical properties included a static tensile test, Charpy impact strength test and Brinellhardness measurement. This work complements the knowledge about alloying additions effect on microstructure and mechanical properties of ADI and focuses on the impact of a single alloying element (Ni).
EN
This work presents the qualitative and quantitative changes in the products of isothermal transformation (reaction) in a ductile cast iron austenite after supercooling to the temperature range Ar1. The austenitizing temperature considered in this work was 900, 960 or 1020°C. The eutectoid reaction was investigated by metallographic examination at a holding temperature right below Ar11 (820°C) or right below Ar12 (760°C). The quantitative metallographic examination was carried out with a light microscope (LM). The initial transformation stage products were identified with a transmission electron microscope (TEM). The selected samples were studied for chemical microsegregation of manganese, silicon, phosphorus, and carbon with an X-ray microanalyser (MAR). The tested cast iron material was found to predominantly feature a eutectoid reaction in the metastable system the ratio of which was increasing with the austenitizing temperature. The austenitizing temperature was found to be conducive to the evolution kinetics of individual phases and to the graphitization kinetics of the eutectoid cementite that was formed during the contemplated reaction.
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EN
Analyses based on FEM calculations have significantly changed the possibilities of determining welding strains and stresses at early stages of product design and welding technology development. Such an approach to design enables obtaining significant savings in production preparation and post-weld deformation corrections and is also important for utility properties of welded joints obtained. As a result, it is possible to make changes to a simulated process before introducing them into real production as well as to test various variants of a given solution. Numerical simulations require the combination of problems of thermal, mechanical and metallurgical analysis. The study presented involved the SYSWELD software-based analysis of GMA welded multipass butt joints made of duplex steel sheets. The analysis of the distribution of stresses and displacements were carried out for typical welding procedure as during real welding tests.
EN
A person is forced to travel constantly throughout its entire life. The more modern the society, the greater the pace of life, and the greater the need to be present in many places that are distant from each other. Rail transport occupies second place in this regard, after air transport. This means of transportation has many advantages, however the time of travel requires continuous improvement, in particular, to match the competition. One factor limiting the speed of travel is inter-operation between the wheels – rail kinematic pair. When rolling on a rail, a wheel is subject to wear, which unavoidably leads to its degradation. Frequent damage to both the wheel and the rail necessitates consideration of this problem. Because any changes to the rail are very expensive and time-consuming, this paper focuses on possible changes to the wheel. This paper is of an analytical nature and is based on sources in the literature, as well as on own simulations. The objective of the paper is to indicate the advantages of using ADI (Austempered Ductile Iron) as a material for the wheel of a railway rolling stock through analysis of available scientific materials and analysis based on a conducted simulation. The application of ADI on a large scale would certainly make a large impact on the development of railway engineering, significantly reducing the costs of manufacturing the product and its future exploitation.
PL
W publikacji zawarto informację dotyczące ogólnej charakterystyki mielników, ich zastosowania i klasyfikacji według obowiązujących norm. Technologia wytwarzania mielników z żeliwa białego została przedstawiona na przykładzie przemysłowej odlewni. Został zobrazowany cały proces produkcyjny od momentu przygotowania wsadu po otrzymanie gotowego produktu.
EN
The publication contains information on the general characteristics of grinding media, their use and classified according to current standards. The technology for producing white iron grinding media is exemplified by the foundry industry. It has been illustrated the manufacturing process after forming the feed in a finished product.
PL
W publikacji zawarto informację dotyczące sposobu poprawy parametrów pracy przekładni mechanicznej pracującej w ujemnej temperaturze. Przedstawiono również systemy rozwiązań dostępnych w sprzedaży dedykowanych do podgrzewania oleju przekładniowego.
EN
The publication contains information on how to improve the operating parameters mechanical transmission operating at a negative temperature. It also presents solutions systems available on the market dedicated to heat the gear oil.
7
PL
W pracy przedstawiono charakterystykę produktów otrzymanych podczas rozdrabniania ziarna pszenicy i kukurydzy za pomocą rozdrabniacza bijakowego. Jako parametry zmienne zastosowano zmienną długość roboczą bujaka: 173, 177, 181 mm.
EN
The characteristics of products obtained during grinding of wheat and corn using a hammer mill is presented in the paper. A variable working length of ram (173, 177, 181 mm) was used as a changeable parameter.
8
Content available remote Badania eksploatacyjne prototypowego rozdrabniacza bijakowego RRMB-803
PL
Celem pracy była ocena wydajności, energochłonności i poziomu hałasu podczas rozdrabniania prototypowym rozdrabniaczem bijakowym RRMB-803. Rozdrabnianiu poddano dwa rodzaje ziarna: pszenicę i kukurydzę. Podczas badań eksploatacyjnych parametrami zmiennymi procesu rozdrabniania były trzy różne długości bijaków, 173, 177, 181 mm oraz cztery średnice robocze otworów sitowych 3, 6,8, 10 mm.
EN
The aim of this study was to evaluate the process efficiency, energy intensity and noise level of the RRMB-803 prototype chopper flail during grinding. Two types of grain, namely wheat and corn were subjected to grinding. Three different beater lengths (173, 177 and 181 mm) and four working diameters of holes sieve (3, 6, 8 and 10 mm) were chosen as operating variable parameters of grinding during the research.
EN
This work presents continuous cooling transformation diagrams for different kinds of carbidic nodular cast iron. We investigated the cast iron, chemical composition of which in nodular cast iron allows the obtainment of a metal matrix which consists of: pearlite, upper bainite and its mixture with lower bainite, ausferrite and martensite when the casts were cooled in the mold. The influence of the rate of cooling on the obtained microstructure and hardness of the casts was shown. The work describes the influence of the alloy additives on the curves of austenite decomposition in the carbidic nodular cast iron. Diagrams were plotted which enable an understanding of the kinetics of the transformations of austenite in carbidic nodular cast iron. The diagrams also indicate the possibility of obtaining pearlite, bainite, martensite and ausferrite with the established chemical composition and the wall thickness of the cast.
PL
W pracy przedstawiono wykresy CTPc różnych rodzajów żeliwa sferoidalnego z węglikami. Zbadano żeliwo o składzie chemicznym zapewniającym uzyskanie w żeliwie sferoidalnym osnowy metalowej złożonej z: perlitu, bainitu górnego oraz jego mieszaniny z dolnym, ausferrytu i martenzytu przy studzeniu odlewów w formie. Pokazano wpływ szybkości studzenia na uzyskiwaną mikrostrukturę i twardość odlewów. Opisano wpływ dodatków stopowych na krzywe rozpadu austenitu w żeliwie sferoidalnym z węglikami. Opracowane wykresy umożliwią poznanie kinetyki przemian austenitu w żeliwie sferoidalnym z węglikami oraz ocenę możliwości uzyskania perlitu, bainitu, martenzytu i ausferrytu przy zadanym składzie chemicznym oraz grubości ściany odlewu.
10
PL
W publikacji podjęto próbę zbadania wpływu temperatury łamania w temperaturach 20°C, 0°C i – 20°C, na udarność żeliwa ADI. Do otrzymania żeliwa ADI użyto dwa wytopy żeliwa sferoidalnego różniące się składem chemicznym. Pierwszy zawierał oprócz pierwiastków podstawowych dodatkowo 0,48% Cu, drugi zaś 0,51% Cu i 0,72% Ni. Wariant obróbczy polegał na jednostopniowym austenityzowaniu w temperaturze tγ = 900°C, podchładzaniu do temperatury przemiany izotermicznej 375°C i wytrzymywaniu w czasie od 15 do 90 min.
EN
This scientific paper presents the research on influence of austenitizing temperature on kinetics and evolution of the spheroidal plain cast iron during eutectoid reaction in isothermal conditions. The cast iron has been austenitized in temperatures of 900, 960 or 1020°C. Therewere two temperature values of isothermal holding taken into consideration: 760 or 820°C. The order of creation of reaction products and their morphology have been analyzed. The particular attention has been paid to the initial stage of transformation. The qualitative research has been executed using the transmission electron microscope (TEM), as well as quantitative research (LM). The influence of austenitizing temperature has also been determined on transformation kinetics and structural composition. It was found that the increase of austenitizing temperature is conductive to the initial release of structures by metastable system. A reduction of time was observed of the initial stage of transformation at temperature close to Ar12 with its simultaneous elongation at temperature close to Ar11, with an increase of austenitizing temperature. The dependences obtained by the metallographic method confirm the prior results of dilatometric research of eutectoid reaction.
EN
One type of spheroidal cast iron, with additions of 0.51% Cu and 0.72% Ni, was subjected to precipitation hardening. Assuming that the greatest increase in hardness after the shortest time of ageing is facilitated by chemical homogenisation and fragmentation of cast iron grain matrix, precipitation hardening after pre-normalisation was executed. Hardness (HB), microhardness (HV), qualitative and quantitative metalographic (LM, SEM) and X-ray structural (XRD) tests were performed. The acquired result of 13.2% increase in hardness after ca. 5-hour ageing of pre-normalised cast iron confirmed the assumption.
13
Content available remote Zastosowanie stali dupleks w przemyśle spożywczym
PL
Stale dupleks, znajdujące zastosowanie w najbardziej agresywnych środowiskach przy produkcji żywności i leków, wykazują pewne trudności w przetwarzaniu (w porównaniu z popularnymi stalami austenitycznymi). Opisano problemy i utrudnienia występujące przy przetwarzaniu stali dupleks. Podano praktyczne wskazówki i wytyczne dotyczące cięcia, przeróbki plastycznej, obróbki mechanicznej oraz spawania stali dupleks.
EN
Duplex steels, used in the most aggressive environments in food and medicines production, reveal some difficulties during processing (in comparison with typical austenitic steels). Issues and obstacles occurring during duplex steel processing are described in the paper. Practical suggestions and guidelines for cutting, forming, mechanical treatment and welding of duplex steels are given.
14
Content available remote Kryteria wyboru technologii spawania zbiornika magazynowego
PL
Omówiono zagadnienie wyboru metody spawania zbiornika magazynowego w warunkach montażowych. Przeprowadzono analizę technologii wykonania dla 4 metod spawalniczych (111, 135, 136, 121). Wzięto pod uwagę następujące kryteria: jakość wykonania, koszt wykonania, wpływ procesu na środowisko, warunki atmosferyczne. Dla wielkogabarytowych cylindrycznych zbiorników magazynowych najefektywniejszą okazała się metoda spawania łukiem krytym pod topnikiem (121).
EN
The issue of selection of storage tank welding methods in assembly conditions is discussed. An analysis of 4 welding methods (111, 135, 136, 121) was performed. The following criteria were taken into account: quality and costs of welding, process impact on environment and weather conditions. The submerged arc welding flux method (121) was proved to be the most effective for the welding of large-sized cylindrical storage tanks.
15
Content available remote Analiza czasu i kosztów spawania zbiornika magazynowego
PL
W pracy przeprowadzono analizy czasu i kosztów wykonania cylindrycznego zbiornika magazynowego o objętości 25 tys. m3 do przechowywania produktów naftowych. Ocenie poddano trzy metody spawania: ręczną - MMA, półautomatyczną - MAG i automatyczną - SAW. Stwierdzono wyższość procesów MAG i SAW nad MMA.
EN
The aim of this study was to analyze time and costs of welding of a cylindrical tank for petroleum products' storage. Three methods of welding were evaluated: the manual - MMA, semiautomatic MAG and automatic - SAW. It was stated that the MAG and SAW processes were better than the MMA method.
EN
Ductile iron was quenched using two-variant isothermal transformation. The first treatment variant consisted of one-phase austenitization at a temperature t = 830, 860 or 900 C, cooling down to an isothermal transformation temperature of 300 or 400 C and holding from 8 to 64 minutes. The second treatment variant consisted of two-phase austenitization. Cast iron was austenitizied at a temperature t = 950 C and cooled down to a supercritical temperature t = 900, 860 or 830 C. Isothermal transformation was conducted under the same conditions as those applied to the first variant. Ferrite cast iron was quenched isothermally. Basic strength (Rp0.2 Rm) and plastic (A5) properties as well as matrix microstructure and hardness were examined. As a result of heat treatment, the following ADI grades were obtained: EN-GJS-800-8, EN-GJS-1200-2 and EN-GJS-1400-1 in accordance with PN-EN 1564:2000 having plasticity of 1.5-4 times more than minimum requirements specified in the standard.
17
Content available remote Charakterystyka fosforanowych powłok konwersyjnych
PL
Celem pracy jest przedstawienie produkcyjnych i użytkowych charakterystyk fosforanowych powłok ochronnych. Opisano wybraną metodę wytwarzania fosforanowej powłoki ochronnej oraz podano przykład jej zastosowania. Przedstawiono przykładową pracującą linię fosforanowania oraz opisano cechy uzyskiwanej powłoki.
EN
A main aim of the paper is to present the production and usable characteristics of phosphate conversion coatings. The paper describes a selected method of protective coating manufacture and gives an example of its application. An example of working phosphatizing process line is shown and the formation of coating after successive trials is described.
EN
Preliminary heat treatment, preceding continuous cooling of the iron casting, assumed in the research, complies with the applied in practice single normalization, double normalization or normalization with slow cooling. In each of these cases continuous cast iron cooling has been begun from the same temperature 925 C. CCT diagrams have been made with use of metallographic method. The mechanism, kinetics and the final structure of eutectoid change of the cast iron after such treatment have been traced.
EN
The article presents various methods for assessment of the austenite volume fraction in Austempered Ductile Iron (ADI). Tests were carried out on two types of ADI, i.e. unalloyed and alloyed with the addition of 0.72% Cu and 0.27% Mo, heat treated under different conditions of isothermal transformation to obtain different austenite volume fractions. The test material was then subjected to metallographic examinations, X-ray diffraction (XRD) analysis, an analysis using the author's genuine programme of artificial neural networks, image analysis and magnetic measurements. The results were compared with each other indicating the possibility of a quantitative measurement of austenite and other phases present in cast iron. It was found that different methods of measurement are not fully consistent with each other but show similar results of the austenite content.
EN
In this work the attempt at quantitative evaluation of the microstructure of ADI cast iron matrix has been made. The automatic analysis of the image of the microstructure of austempered spheroidal cast iron has been used for the evaluation. The treatment variant was a two-phase austenitization. First phase was carried out at a temperature t�Á = 950 0C and after cooling to a temperature t�Á�f = 900 0C. The isothermal process was carried out at a temperature tpi = 300 and 400 0C for 8 �€ 64 min. Ordinary cast iron was austempered. After it the microstructure images were recorded and subjected to automatic image analysis with the use of the NIS ELEMENTS 3,0 AR software.
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