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PL
W ramach prac projektu międzynarodowego realizowanego w Instytucie Odlewnictwa w Krakowie we współpracy z Energy Industries of Ohio opracowano technologię topienia w otwartym piecu indukcyjnym i grawitacyjnego odlewania nadstopów niklu. Dotychczas nadstopy te stosowane były wyłącznie jako przerabiane plastycznie. Do kontroli jakości wykonanych odlewów ze stopu Haynes 282 (H282) zastosowano między innymi rentgenowską tomografię komputerową (ang. Computed Tomography, CT). Jest to metoda nieniszcząca, która łączy badania rentgenowskie z zaawansowaną technologią komputerową. W niniejszej pracy zaprezentowano wybrane przykłady uzyskanych wyników badań zrealizowanych za pomocą rentgenowskiego tomografu komputerowego firmy GE Phoenix typu v/tome/x l-450 będącego na wyposażeniu Instytutu Odlewnictwa. Wszystkie operacje związane z obróbką danych z CT były wykonywane za pomocą oprogramowania datos/x - reconstruction i VGStudio Max 2.0.
EN
As a part of the international project carried out at the Foundry Research Institute in Krakow in cooperation with Energy Industries of Ohio, anopen induction furnace melting technology and gravity casting of nickel superalloys have been developed. These alloys have been processed plastically so far. Quality control of Haynes 282 alloy (H282), was made with X-ray computed tomography (CT). CT is a non-destructive method that combines X-ray examinations with advanced computer technology. Selected results of the research obtained from the X-ray computer tomograph have been presented in the paper. Research were made by using the GE Phoenix v/ tome/x l-450 tompgraph type belonging to the Foundry Research Institute equipment. All operations related to the processing of CT data were performed using the datos/x-reconstruction and VGStudio Max 2.0 software.
EN
The main aim of this investigation was to determine the microstructural degradation of Inconel 713C superalloy during creep at high homologous temperature. The alloy in as cast condition was characterized by large microstructural heterogeneity. Inside equiaxed grains dendrite cores consisted of γ' precipitates surrounded by channels of matrix, whereas enrichment of interdendritic spaces in carbide formers, Zr and B resulted in the formation of additional constituents, namely M3B2, Ni7Zr2 and eutectic island γ/γ'. Directional coarsening of γ′ precipitates (rafting) under applied stress and decomposition of primary MC- type carbides accompanied by the formation of secondary carbides enriched in Cr and γ' phase was observed.
PL
Głównym celem badania było określenie degradacji mikrostruktury nadstopu Inconel 713C zachodzącej podczas badania pełzania w wysokiej temperaturze homologicznej. Badany nadstop bezpośrednio w stanie lanym charaktery- zuje się wysoką niejednorodnością mikrostrukturalną. Wewnątrz ziaren równoosiowych rdzenie dendrytów składają się z wydzieleń γ' otoczonych kanałami osnowy, natomiast wzbogacenie przestrzeni międzydendrytycznych w pier- wiastki węglikotwórcze, a także Zr i B, prowadzi do tworze- nia dodatkowych składników, mianowicie eutektyki γ/γ', wę- glików MC, borków M3B2 oraz fazy międzymetalicznej Ni7Zr2. W trakcie pełzania przy parametrach T = 982ºC i naprężeniu σ = 152 MPa zaobserwowano rafting typu N fazy międzymetalicznej γ'. W przestrzeniach międzydendrytycznych w wyniku częściowego rozpuszczenia węglików typu MC wydzieliły się węgliki M23C6 bogate w Cr.
EN
The effect of cobalt aluminate inoculant addition and melt-pouring temperature on the structure and mechanical properties of Ni-based superalloy was studied. The first major move to control the quality of investment cast blades and vanes was the control of grain size. Cobalt aluminate (CoAl2 O4 ) is the most frequently utilized inoculant in the lost-wax casting process of Ni-based superalloys. The inoculant in the prime coat of moulds and pouring temperature play a significant role in grain size control. The finest surface grains were obtained when the internal surface of shell mould was coated with cobalt aluminate and subsequently pouring was at 1480°C. The influence of selected casting parameters and inoculant addition on mechanical properties was investigated on the basis of tensile, creep and hardness testing. The effect of grain refinement on mechanical properties were consistent with established theories. Tests conducted at ambient temperature indicated a beneficial effect of grain refinement both on tensile strength and hardness. In contrast at elevated temperature during creep, the reverse trend was observed.
EN
The aim of this study is to investigate influence of selected parameters of gas tungsten arc welding on microstructure of MAR-M247 nickel based superalloy originating from turbine vane. MAR-M247 is a precipitation-strengthened superalloy which is widely used in aerospace engines. The main strengthening phase in this material is ordered L12 intermetallic γ' phase Ni3 (Al, Ti). The surface of alloy was modified by electric arc in order to present microstructural changes in weld and heat affected zone. Investigation of the heat affected zone revealed that constitutional liquation of γ' particles and primary carbides is responsible for the formation of a liquid grain boundary layer which finally contributed to cracking. Scanning electron microscopy indicated high susceptibility to cracking of MAR-M247 alloy which is connected with high content of γ'-formers aluminum and titanium.
EN
The aim of the present study was to characterize the repair weld of serviced (aged) solid-solution Ni-Cr-Fe-Mo alloy: Hastelloy X. The repair welding of a gas turbine part was carried out using Gas Tungsten Arc Welding (GTAW), the same process as for new parts. Light microscopy, scanning electron microscopy, transmission electron microscopy, microhardness measurements were the techniques used to determine the post repair condition of the alloy. Compared to the solution state, an increased amount of M6C carbide was detected, but M23C6 carbides, sigma and mu phases were not. The aged condition corresponds to higher hardness, but without brittle regions that could initiate cracking.
PL
Artykuł przedstawia wybrane formy składowania danych tj. Local Storage, Shared Preferences, pliki płaskie oraz SQLite w kontekście dwóch systemów mobilnych – Android oraz Windows Mobile. Opisuje on również sposoby, poprzez które możliwe jest połączenie z zewnętrznymi systemami bazodanowymi takimi jak Microsoft SQL Server, PostgreSQL czy MySQL i stara się odpowiedzieć na pytanie, użycie której z tych opcji ma największy sens w poszczególnych przypadkach. Całość argumentuje badaniami wydajności, którym poddane zostały wszystkie z wymienionych opcji.
EN
This publication presents chosen forms of data persistence such as: Local Storage, Shared Preferences, flat files and SQLite in the context of two widely used mobile operating systems – Android and Windows Mobile. It also describes ways to connect to external database engines such as Microsoft SQL Server, PostgreSQL or MySQL and tries to answer the question which one of these data persistence forms makes the most sense and when. The arguments are based on performance tests that all of the described solutions were participants of.
EN
The following paper investigates two model alloys simulating the quenched matrix of high-speed steels with an addition of 1.5% Ni, which was enriched with 1% and 2% of Nb to increase abrasion resistance. Based on the alloys’ composition comprising of W, Mo, V and Cr, the simulations of the quenched matrix of the high-speed steels indicate sufficiently high hardenability. The purpose of increasing the nickel content in the composition of such alloys was to increase their crack resistance, whereas the addition of the strongly carbide-forming niobium in amounts of 1% and 2%, balanced by an additional carbon content, was aimed at increasing the abrasion resistance of these steels. The authors of the above mentioned chemical composition concept expect that these types of alloys will be used in the production of tools (rolls) designed for the rolling of metallurgical products which are difficult to produce (flat bars, channel bars and tee bars). The quenching temperature of both alloys was optimised on the base of the so called quenching series. The accurate CCT diagrams and the tempering series for revealing the secondary hardness effect were also performed for these alloys. All investigation stages were accurately documented by metallographic tests.
PL
W pracy postanowiono wznowić badania na osnowie zahartowanej stali szybkotnącej, jednakże jej skład uzupełniono dodatkiem około 1,5% Ni oraz dodatkami odpowiednio około 1% i 2% Nb. Dodatki niobu, jeżeli tylko zostaną zbilansowane odpowiednimi dodatkami węgla, powinny dzięki utworzeniu stabilnych węglików Nb4C3 zwiększyć odporność na ścieranie stopu, a dodatki niklu powinny zwiększyć jego odporność na pękanie. Takie postępowanie powinno umożliwić uzyskanie materiału narzędziowego odpornego na ścieranie oraz odpornego na pękanie o właściwościach zahartowanej osnowy stali szybkotnących. Autorzy składu chemicznego nowych stopów i ich koncepcji spodziewają się, że będą one stosowane do wytwarzania narzędzi (walców) przeznaczonych do walcowania produktów hutniczych, które są trudne do wytworzenia (płaskowników, ceowników oraz teowników).
8
Content available remote Phase transformations in the precipitation hardened cast steel
EN
Purpose: The microstructure of the new ledeburitic, tool cast steel of the precipitation hardened matrix was designed. The concept of this microstructure was based on the microstructure of the steel-bonded carbides [1,2], in which a skeleton is built of sintered carbides. This skeleton is produced by the powder metallurgy methods and then filled with melted steel of the selected chemical composition. Design/methodology/approach: The new cast steel of the structure analogous to the steel-bonded carbides was conventionally melted in a furnace, however with omitting pressing and sintering operations of the powder metallurgy. The carbides skeleton in the new cast steel is formed by carbides of the MC type forming jointly ledeburite and its matrix constitutes steel hardened by precipitates of intermetallic compounds. This new material will be destined for tools of a moderate hardness (approximately 40 HRC), high abrasion resistance and high strength. Findings: Utilising hard carbides forming by elements of VB group of the Mendeleev’s table it is possible to design the tool material similar to the steel-bonded carbide of the selected matrix composition and primary carbides of MC type. Research limitations/implications: The chemical composition the matrix of designed material decides on its hardness and strength, the MC type carbides decide on the abrasion resistance and if they occur in the eutectic form they decide on a rather low fracture toughness. Therefore efforts should be undertaken to have non-ledeburitic materials. Practical implications: As a result of these investigations a new precipitation hardened cast steel have been worked out and a possibility of its industry applied was shown. Originality/value: The results of investigations of phase transformations in the new cast steel at its heating and cooling from the austenite range, are presented in the hereby paper.
PL
Młodzieńcza kifoza piersiowa (choroba Scheuermanna) prowadzi do zmian statyczno-dynamicznych w obrębie kręgosłupa, obręczy barkowej i biodrowej, a tym samym do powstania przykurczów mięśniowo-torebkowych oraz osłabienia rozciągniętych mięśni i więzadeł. Celem pracy jest przedstawienie możliwości wykorzystania metody PNF (torowanie nerwowo-mięśniowe - proprioceptive neuromuscular facilitation) i kinesiotapingu w leczeniu młodzieńczej kifozy piersiowej. Metody te pozwalają na przywrócenie prawidłowej równowagi mięśniowej poprzez rozciągnięcie i wzmocnienie przykurczonych i osłabionych mięśni. Poprawiają także zakres ruchomości stawów i ułatwiają naukę utrzymywania prawidłowej postawy ciała.
EN
Juvenile thoracic kyphosis leads to the static and dynamic changes within the spine and the pelvic girdle, musculo-capsu-lar spasms and adynamia in overextended muscles, as well as ligaments. This paper presents the potential applications of PNF (Proprioceptive Neuromuscular Facilitation) method and kinesiotaping in a treatment of the juvenile thoracic kyphosis (Scheuermann's disease). These therapeutic methods are useful in restoration of the normal muscular balance by stretching the contracted muscles and strengthening the impaired ones. Thus, the correct range of joint movement may be achieved and the patient is able to maintain the proper body posture.
PL
Od 2003 r. w laboratorium VIGO/WAT prowadzono badania nad wzrostem heterostruktur Hg1-xCdxTe o niemal dowolnych profilach składu i poziomie domieszkowania, niezbędnych dla zaawansowanych przyrządów fotoelektrycznych. MOCVD w zastosowaniu do Hg1-xCdxTe jest jedną znajtrudniejszych technologii epitaksjalnych. Omówiono zagadnienia związane ze wzrostem i charakteryzacją warstw Hg1-xCdxTe w technologii MOCVD. Dokonano pomiarów insitu względnego stężenia związków metaloorganicznych analizatorem gazu własnej konstrukcji. Podsumowano stan domieszkowania warstw Hg1-xCdxTe z uwzględnieniem ostatnich badań. Opracowana technologia MOCVD została zastosowana do otrzymywania wszystkich typów produkowanych w VIGO System detektorów podczerwieni pracujących w temperaturach pokojowych.
EN
Since 2003 VIGO System S.A. together with MUT (Military University of Technology) are doing joint efforts to improve MOCVD growth of Hg1-xCdxTe. Photodetectors optimized for any wavelength within 1-15 um spectral range requires complex heterostructures with multiple layers with homogeneous composition and doping, characterized by steep interfaces. Hg1-xCdxTe growth with interdiffused multilayer process (IMP) technique has been improved using self-made in-situ monitoring of gas delivery to the growth zone. The other issues addressed in this work were growth of heavy As-doped low-x and heavy l-doped high-x materials. Special modification to IMP process has been applied for in-situ control of stoichiometry. To maintain low vacancy concentration, special growth finish procedure has been developed. No post-growth thermal anneal was necessary for device-quality material. The MOCVD grown heterostructures have been successfully used for advanced uncooled infrared photodetectors such as multiple heterojunction photodiodes, multicolor and multiabsorber devices with specially shaped spectral response.
PL
Omówiono zagadnienia rozwoju małych firm zajmujących się zaawansowanymi technologiami elektronicznymi w Polsce. Na przykładzie firmy VIGO System S.A. pokazano możliwości skutecznego opanowania nisz w dziedzinie optoelektroniki na rynku światowym. Przedstawiono metody umacniania pozycji konkurencyjnej i wizerunku firmy na rynku.
EN
Some issues of development of small, high-tech electronics, enterprises in Poland are discussed. Based on an example of VIGO System S.A., the possibility of world niche market capturing, company competition position and image reinforcement has been shown.
14
Content available remote Growth of MOCVD HgCdTe heterostructures for uncooled infrared photodetectors
EN
In the paper recent progress at VIGO/MUT (Military University of Technology) MOCVD Laboratory in the growth of Hg1-xCdx Te (HgCdTe) multilayer heterostructures on GaAs/CdTe substrates is presented. The optimum conditions for the growth of single layers and complex multilayer heterostructures have been established. One of the crucial stages of HgCdTe epitaxy is CdTe nucleation on GaAs substrate. Successful composite substrates have been obtained with suitable substrate preparation, liner and susceptor treatment, proper control of background fluxes and appropriate nucleation conditions. The other critical stage is the interdiffused multilayer process (IMP). The growth of device-quality HgCdTe heterostructures requires complete homogenization of CdTe-HgTe pairs preserving at the same time suitable sharpness of composition and doping profiles. This requires for IMP pairs to be very thin and grown in a short time. Arsenic and iodine have been used for acceptor and donor doping. Suitable growth conditions and post growth anneal is essential for stable and reproducible doping. In situ anneal seems to be sufficient for iodine doping at any required level. In contrast, efficient As doping with near 100% activation requires ex situ anneal at near saturated mercury vapours. As a result we are able to grow multilayer fully doped (100) and (111) heterostructures for various infrared devices including photoconductors, photo electromagnetic and photovoltaic detectors. The present generation of uncooled long wavelength infrared devices is based on multijunction photovoltaic devices. The technology steps in fabrication of devices are described. It is shown that near-BLIP performance is possible to achieve at c.a 230 K with optical immersion. These devices are especially promising as 7.8-9.5-J-[mu]m detectors, indicating the potential for achieving detectivities above 10 do potęgi 9 cmHz1/2/W.
15
EN
We report here recent progress at VIGO/WAT MOCVD Laboratory in the growth of Hg₁₋xCdxTe (HgCdTe) multilayer heterostructures on GaAs/CdTe and other composite substrates for uncooled infrared photodetectors. The optimum conditions for the growth of single layers and complex multilayer heterostructures have been established. One of the crucial stages of the technology was CdTe nucleation on GaAs substrate. Successful composite substrates were obtained with suitable substrate preparation, liner and susceptor treatment, proper control of background fluxes and appropriate nucleation conditions. The other critical stage is the interdiffused multilayer process (IMP). The growth of device-quality HgCdTe heterostructures requires complete homogenization of CdTe-HgTe pairs preserving at the same time suitable sharpness of composition and doping profiles. This requires for IMP pairs to be very thin and grown in a short time. The practical implications for the IMP process are the CdTe/HgTe growth times that become comparable with transition times between the phases, characteristic for the MOCVD machine. The growth during transition stages is characterized by the non-optimum flow velocities and partial pressures that may induce poor morphology, reduce growth rate and cause other problems. This became especially acute for doped layers when large Cd/Te ratio is required for efficient incorporation and full activation of dopants. This has been solved by careful selection of hydrogen carrier gas and metaloorganics fluxes with suitable switching on and off times. Arsenic and iodine has been used for acceptor and donor doping. Suitable growth conditions and post growth anneal is essential for stable and reproducible doping. In-situ anneal seems to be sufficient for iodine doping at any required level. In contrast, efficient As doping with near 100% activation requires ex situ anneal at near saturated mercury vapors. As the result, we are able to grow multilayer fully doped (100) and (111) heterostructures for various infrared devices including photoconductors, photoelectromagnetic and photovoltaic detectors.
16
Content available remote Electromagnetic limit of the optical gain for long-wave IR diffractive optics.
EN
Focal plane collection optics consisting of arrays of microlenses may be used to reduce the physical size of an infrared detector without reduction of its apparent optical size and quantum efficiency. This results in reduction of the thermal generation rate in the detector, allowing improvement of performance of infrared devices operating at elevated temperatures. We report on calculations of the optical gain achievable with the use of diffractive microlenses for long-wave (8-22 mu m) infrared (LWLR) detectors. Fast diffractive lenses are required for this application, and binary optics is the most popular technology of their fabrication. A large fraction of the binary lens surface relief is built of staircase annular structures whose width is of wavelength-scale. Therefore, the electromagnetic theory of gratings has been applied in the paper to calculate the diffraction efficiency of the Fresnel zones for the multi-phase-level lenses. It is shown that electromagnetic effects limit the speed of the LWIR diffractive lenses.
17
Content available remote Detektory podczerwieni dla amunicji inteligentnej
PL
Przedstawiono tendencje rozwojowe detektorów promieniowania podczerwonego dla amunicji inteligentnej. Współczesne technologie umożliwiają otrzymywanie nieselektywnych detektorów termicznych oraz fotodetektorów śedniej i dalekiej podczerwieni, niezbędnych do pasywnej detekcji celów, o charakterystykach bliskich do teoretycznych granic. Podstawowe tendencje to rozwój matryc o dużej ilości elementów, zmniejszenie lub nawet pełne wyeliminowanie chłodzenia detektorów praz obniżenie kosztów produkcji. Przedstawiony został również stan prac nad detektorami podczerwieni w Polsce.
EN
Research and development studies carried out in a high-tech company VIGO-System Ltd are described. This company produces infrared detectors as well as various electronic and optical systems, based on the own original design and innovative technical solutions. An attempt is undertaken to enumerate those actions of management, which could make possible to adapt such a company to demands and needs of the international market.
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