Filters
total: 1447
-
Catalog
displaying 1000 best results Help
Search results for: cracks in welds
-
Friction stir welds (FSW) of aluminium alloy AW6082-T6
PublicationW pracy przedstawiono badania właściwości mechanicznych złącz stopu aluminium AW6082-T6 wykonanych metodą tarciowego zgrzewania z wymieszaniem zgrzeiny. Złącza wykonano z różnymi parametrami procesu technologicznego. Wykazano, że wytrzymałość złącz jest proporcjonalna do prędkości zgrzewania oraz, że spadek twardości SWC jest większy po stronie ''advancing'' złącz.
-
Mechanical properties and corrosion resistance of dissimilar stainless steel welds
PublicationW artykule przedstawiono właściwości mechaniczne oraz odporność korozyjną doczołowych złączy różnoimiennych stali odpornych na korozję, austenitycznej 316L oraz duplex 2205. Blachy o grubości 15 mm spawano automatycznie łukiem krytyn z różnymi energiami liniowymi. Wykazano, że właściwości mechaniczne złączy spełniają wymagania okrętowych towarzystw klasyfikacyjnych, natomiast najbardziej narażoną strefą złącza na działanie korozji...
-
Assessment of FSW Welds Made of Aluminum Alloy AW7075-T651.
PublicationThis paper summarizes the results of experimental studies in which the aluminum alloy AW7075-T651 was friction stir welded (FSW) using various combinations of process parameters (rotational - R and travel speed - T). Mechanical properties of the test welds were assessed by using static tensile test and Vickers hardness measurement. The temperature of the welded plates was monitored during welding by means of thermocouples placed...
-
Designate CTOD of Weld Metal of butt weld, No WOiO/II/108/2013
PublicationTypical (normative) testing of materials and/or welded joints do not answer on all questions about material or welded joint properties. In ship building and off-shore sectors, many strucures requires materials and joint with higher than typical fatigue resistance. Imact tests, which are carried out during welding technology qualification, gives answer about ductility, CTOD tests results about material or welded joint ability...
-
Effect of Storage Conditions of Rutile Flux Cored Welding Wires on Properties of Welds
PublicationThe influence of storage locations of two grades of rutile flux cored welding wires on their surface condition and the strength of the welds made with them were studied. Wires were stored in real urban conditions (Gdańsk and Katowice) for 1 month, simultaneously recording changes in conditions: temperature and relative humidity of the environment. Visual tests of wires in the delivered and stored condition as well as visual and...
-
Selection of Electrode Material for Inconel 617/P92 Steel SMAW Dissimilar Welds
PublicationThe present work aimed to investigate the microstructure and mechanical properties of the dissimilar shielded metal arc welded (SMAW) joint of Alloy 617 and P92 steel for advanced ultrasupercritical boilers. The SMAW joint was produced using three different types of electrodes, namely, ENiCrFe-3, ENiCrMo-3, and ENiCrCoMo-1. During microstructural observation of the welded joints, no possible cracking was detected in the weldments....
-
Clocks & Sleep
Journals -
INFLUENCE OF TACK WELDS DISTRIBUTION AND WELDING SEQUENCE ON THE ANGULAR DISTORTION OF TIG WELDED JOINT
PublicationIn this paper the influence of tack welds distribution and welding sequence on angular distortion of the Tungsten Inert Gas (TIG) welded joint was tested. Additionally, the effect of welding current on angular distortion was assessed. For research X2CrTiNb18 (AISI 441) stainless steel (2.5 mm thick) was chosen. During research specimens were prepared with different distributionsof tack...
-
Manufacturing Parameters, Materials, and Welds Properties of Butt Friction Stir Welded Joints–Overview
PublicationThe modern and eco-friendly friction stir welding (FSW) method allows the combination of even such materials that are considered to be non-weldable. The development of FSW technology in recent years has allowed a rapid increase in the understanding of the mechanism of this process and made it possible to perform the first welding trials of modern polymeric and composite materials, the joining of which was previously a challenge....
-
Continuous and discontinuous modeling of cracks in concrete elements
PublicationW artykule przedstawiono różne sposoby modelowania rys w elementach betonowych w warunkach mieszanego sposobu obciążenia przy zastosowaniu modeli ciągłych i nieciągłych. Symulacje wykonano przy zastosowaniu 3 różnych modeli ciągłych: modelu sprężysto-plastycznego, modelu w ramach mechaniki zniszczeniowej i modelu rys rozmytych z rysami obracającymi się oraz 1 modelu nieciągłego przy zastosowaniu stref kontaktu..
-
The determination of deformations and stresses of laser welds used for fatigue assessment of steel sandwich panel joints
PublicationPanele typu sandwich znajdują szerokie zastosowanie w wielu gałęziach przemysłu. W przypadku niektórych zastosowań wymagających ocenę ryzyka dużą rolę odgrywa ocena trwałości zmęczeniowej spoin laserowych paneli. W pracy prezentowane są metody wyznaczania lokalnych odkształceń i naprężeń w połączeniach spawanych w celu oceny trwałości zmęczeniowej według hipotez lokalnych naprężeń i odkształceń.
-
Analysis of Residual Stresses and Dislocation Density of AA6082 Butt Welds Produced by Friction Sir Welding
PublicationThe Friction Stir Welding (FSW) method was employed to join AA6082 sheets. The welds were produced with different tool traverse speed (200 and 250 mm/min), rotational speed (1000 and 1250 RPM) and tool tilt angle (0 and 2 deg). Based on the analysis of XRD patterns, the total precipitation volume fractions in the nugget zones and the base material were calculated. The FSW process resulted in a reduction in the fraction of precipitates...
-
Plasticity of Bead-On-Plate Welds Made with the Use of Stored Flux-Cored Wires for Offshore Applications
PublicationExtreme atmospheric conditions in the marine and offshore industry are harmful to engineering materials, especially to welded joints, and may cause degradation of their properties. This article presents the results of research on the plasticity of bead-on-plate welds made using two types of seamless, copper plated flux-cored wires. Before welding, spools with wire were stored for 1 month in two distinct locations with different...
-
Biodiversity of Weeds in Fields of Grain in South-Eastern Poland
Publication -
Mechanism of the fatigue cracks development in bearing slide layer
PublicationNa podstawie literatury przedstawiono wybrane problemy dotyczące powiązania wytrzymałości zmęczeniowej łożysk ślizgowych ze strukturą i charakterystyką materiału tworzącego warstwę ślizgową panwi.W szczególności analizowano mechanizm inicjacji i propagacji pęknięć zmęczeniowych jako zależną nie tylko od wzorca obciążenia dynamicznego, lecz również od geometrii i struktury warstwy ślizgowej.Wyróżniono dwa typy pęknięć: strukturalne...
-
The influence oil additives on spread cracks in silicon nitride
PublicationThe paper presents an experimental study of the influence of oil additives (Cl, S, P, cerium dioxide (CeO2)) on spread cracks in silicon nitride. The additives Cl, S, P are bound in molecules in liquid form soluble in the base oil. The CeO2 is purely in powder form in suspension. The use of CeO2 powder was made based on the good results of polishing of silicon nitride. A ceramic angular contact ball bearing was modelled using a...
-
Prediction of Weld Deformations by Numerical Methods - Review
PublicationThe welding process is the basic technique of joining in the shipbuilding industry. This method generates welding distortions that cause a lot of problems during the manufacturing process due to both the time and cost of straightening as well as their influence on later stages of production. Proper preparation of welding processes plays a growing role in the shipbuilding industry and the development of calculating tools is being...
-
Soils and Rocks
Journals -
Study on Microstructure-Property Relationship of Inconel 617 Alloy/304L SS Steel Dissimilar Welds Joint
PublicationWelding of Inconel 617 (IN617) alloy and austenitic 304L SS steel has been attempted using the autogenous Laser Beam Welding (LBW) process. Characterization of dissimilar weldments was performed on either side of the fusion boundaries. The metallographic results showed that the inhomogeneous microstructure formation for weld metal contained columnar and cellular dendrites near the interface, whilst the columnar, cellular and equiaxed...
-
Welds sample 2
Open Research DataIn this series of experimental data, videos of the stretching of welded parts will be presented. To watch movies in .cine format, you need to have Phantom's dedicated free software viewer installed.
-
Welds sample 1
Open Research DataIn this series of experimental data, videos of the stretching of welded parts will be presented. To watch movies in .cine format, you need to have Phantom's dedicated free software viewer installed.
-
Welds sample 1Z
Open Research DataIn this series of experimental data, videos of the stretching of welded parts will be presented. To watch movies in .cine format, you need to have Phantom's dedicated free software viewer installed.
-
Welds sample 1Hb
Open Research DataIn this series of experimental data, videos of the stretching of welded parts will be presented. To watch movies in .cine format, you need to have Phantom's dedicated free software viewer installed.
-
Welds sample 2CA1
Open Research DataIn this series of experimental data, videos of the stretching of welded parts will be presented. To watch movies in .cine format, you need to have Phantom's dedicated free software viewer installed.
-
Welds sample 1Ca
Open Research DataIn this series of experimental data, videos of the stretching of welded parts will be presented. To watch movies in .cine format, you need to have Phantom's dedicated free software viewer installed.
-
Welds sample 1Eb
Open Research DataIn this series of experimental data, videos of the stretching of welded parts will be presented. To watch movies in .cine format, you need to have Phantom's dedicated free software viewer installed.
-
Cracow Indological Studies
Journals -
Damage of a post-tensioned concrete bridge – Unwanted cracks of the girders
PublicationThe cracking of a post-tensioned T-beam superstructure, which was built using the incremental launching method, is analyzed in the paper. The problem is studied in detail, as specific damage was observed in the form of longitudinal cracks, especially in the mid-height zone of the girder at the interface of two assembly sections. The paper is a case study. A detailed inspection is done and non-destructive testing results of the...
-
Guided waves for monitoring of plate structures with linear cracks of variable length
PublicationDamage occurring at the work of plate structures may grow to a considerable size. The joint action – the detection of a defect at the earliest possible stage, the monitoring of its growth and the determination of its critical size in the context of structural reliability allows optimizing the cost of the maintenance and repair of structural elements. Thus the development of monitoring systems for permanent observation of fault...
-
J. FE modelling of cracks in concrete elements within continuum mechanics.
PublicationW artykule przedstawiono wyniki symulacji rys zakrzywionych w elementach betonowych w warunkach mieszanego sposobu obciążenia. Symulacje wykonano przy zastosowaniu 3 różnych modeli: modelu sprężysto-plastycznego, modelu w ramach mechaniki zniszczeniowej i modelu z rysami obracającymi się.
-
Formation and Growth of the Crack in Bonded Joints Under Mode I Fracture: Substrate Deflection at Crack Vicinity
PublicationAdhesive bonding is now commonly used in aircraft, cars, boats, etc. In these applications, thin panels are often bonded. In such thin structures, heterogeneous mechanical loading along the bondline edge (or potential crack front), is likely to arise due to 3D structural effects. The crack front and its vicinity is a special region, in that it is where structural properties of the adherend material meet those of the adhesive (discontinuity)....
-
On the crack front curvature in bonded joints
PublicationStandard tests of adhesively bonded specimens are likely to produce heterogeneous stress distribution along the crack front and its vicinity. High separation rate mode I dominated fracture test is performed.Observation of post mortem fractured surfaces with an optical microscope reveals characteristic features of mixed mode I/III fracture near the sides of the specimen but not in the middle. At first, finite elements calculations...
-
Ultralow lasing thresholds of VCSEL-type resonators with periodically structured quantum wells
Publication -
Wady powierzchniowe ceramicznych elementów tocznych = Surface cracks of ceramic rolling elements
PublicationMateriały ceramiczne posiadają kombinację optymalnych własności, które są niezbędne w zastosowaniach na wysoko obciążone elementy maszyn. Podstawowym problemem związanym z wytrzymałością zmęczeniową materiałów ceramicznych są wszelkiego rodzaju wady powierzchniowe będące efektem procesu wytwarzania lub wynikające z defektów struktury materiału ceramicznego. W artykule przedstawiono badania doświadczalne dwutlenku cyrkonu ze sztucznie...
-
Nondestructive methods complemented by FEM calculations in diagnostics of cracks in bridge approach pavement
PublicationNondestructive methods of road pavement diagnostics are an alternative to traditional approach to pavement failure investigation. The article presents a detailed multidisciplinary inspection carried out using ground-penetrating radar (GPR), laser scanning technology and finite element method (FEM) calculations. It was done in order to assess the factors that contributed to occurrence of premature cracks of a bridge approach pavement....
-
Analysis of ring cracks in ceramic rolling elements using the boundary element method
PublicationCeramic materials have been increasingly used in bearing technology for over a dozen years. This is due to the characteristic properties of ceramic materials such as: high hardness, corrosion resistance, the possibility of use in aggressive chemical environments, as well as due to the lower specific weight compared to steel materials. However, the use of ceramic materials is connected with many limitations. The main disadvantages...
-
A constitutive law for concrete with smooth transition from continuous into discontinuous cracks’ description
PublicationPaper presents a constitutive model for concrete that combines a continuous and discontinuous crack’s description to simulate the concrete under tensile dominated loads. In a continuum regime, two different constitutive laws were used. First, a plasticity model with the Rankine failure criterion and an associated flow rule was used. Second, a constitutive law based on isotropic damage mechanics was formulated. Both model alternatives...
-
Opinion about causes of framing of Kingston chest (box cooler) damage, on PSV vessel VS4411 DF-PSV (B-855)
PublicationThe subject of analysis is a damage of welded connection of box cooler framing segments, made as separate bars 50mm thickness, connected by the welds in corners. Studies of documents delivered by Customer shows cracks on the fusion of filet welds and twisting of box cooler frame. The subject of analysis is a damage of welded connection of box cooler framing segments, made as separate bars 50mm thickness, connected by the welds...
-
The Influence of Modelling Material Zones on Strains and Stresses at Weld Toe Notch
PublicationThe latest development in the field of welding technology enabled prefabrication of thin-walled sandwich structures in an industrial scale. Sandwich structures fabricated of steel, or aluminium alloy plates and stiffeners are welded with the use of hi-power CO2 lasers. Strength analysis of such structures with the use of finite element method needs proper material modelling.In this paper the material model of steel sandwich panel...
-
SPRINGER TRACTS IN MODERN PHYSICS
Journals -
Gaceta Medica de Caracas
Journals -
Simulations of Shear Zones and Cracks in Engineering Materials Using eXtended Finite Element Method
PublicationNumerical simulations of cracks and shear zones in quasi-brittle materials are presented. Extended Finite Element Method is used to describe both cracks and shear zones. In a description of tensile cracks, a Rankine criterion is assumed. A discrete Mohr-Coulomb law is adopted for simulations of shear zones. Results of simple numerical tests: unixial tension, bending and biaxial compression are demonstrated.
-
Crack propoagation in MgO-PSZ ceramic materials
PublicationThe properties of ceramic materials such as elevated hardness, high temperature capability, low coefficient of thermal expansion are of interest for rolling element materials. Widely used ceramic materials in engineering applications are silicon nitride, zirconia and alumina. The paper presents an experimental study of the fatigue life of MgO-PSZ ceramic material in lubricated contact with defined types of cracks. A ceramic angular...
-
Numerical analysis of crack propagation in silicone nitride
PublicationThe properties of ceramics, specifically low density, high hardness, high temperature capability and low coefficient of thermal expansion are of most interest to rolling element manufacturers. The influence of ring crack size on rolling contact fatigue failure has been studied using numerical fracture analysis. Such cracks are very often found on ceramic bearing balls and decrease fatigue life rapidly. The numerical calculation...
-
Hertzian Crack Propagation in Ceramic Rolling Elements
PublicationThe properties of ceramics are of most interest to rolling element manufacturers. The influence of ring crack size on rolling contact fatigue failure has been studied using numerical fracture analysis. Such crack are very often found on ceramic bearing balls and decrease fatigue life rapidly. The numerical calculations are based on a three dimensional model for the ring crack propagation. The stress intensity factors along crack...
-
Crack identification in cantilever beam using wavelets
PublicationPrzedstawiono metodę identyfikacji zniszczeń przy użyciu transformacji falkowej. Rozpatrzono przykład belki wspornikowej. Pokazano, że transformacja falkowa wykrywa miejsce zniszczenia.
-
Wave propagation in plate structures for crack detection.
PublicationW pracy przedstawiono analizę propagacji fali poprzecznej w płycie z pęknięciem. Do modelowania zagadnienia zastosowano metodę elementów spektralnych.
-
Wave propagation in plate structures for crack detection
Publication -
Propagation of in-plane waves in an isotropic panel with a crack
PublicationW pracy przedstawiono model tarczowego elementu spektralnego do analizy propagacji fali wzdłuznej w panelach z uszkodzeniami.
-
Evolutionary Planning of Safe Ship Tracks in Restricted Visibility
PublicationThe paper presents the continuation of the author's research on ship track planning by means of Evolutionary Algorithms (EA). The presented method uses EA to search for an optimal set of safe tracks for all ships involved in an encounter. Until now the method assumed good visibility – compliance with standard rules of the Convention on the International Regulations for Preventing Collisions at Sea (COLREGS, 1972). However, in restricted...
-
The Influence of Selected Parameters of Numerical Modelling on Strains and Stresses at Weld Toe Notch
PublicationLatest development in the field of welding technology and prefabrication enabled massive production of thin-walled sandwich structures. Multi-layered sandwich structures are fabricated with the use of high-power CO2 lasers, friction welding, arc welding, hybrid welding, or other technique designed for the special purpose. Steel or aluminium alloy plates with thickness between 1 and 5 mm are connected by internal stiffeners. Strength...
-
FEM modelling of stress and strain distribution in weld joints of steel sandwich panels
PublicationThe development of laser welding technology has enabled the mass production of thin-walled structures, including steel sandwich panels. The technology of joining plating panels with stiffeners by welding allows us to create joints with a specific geometry and material properties. In comparison with other types of joints, laser welds are characterized by their specific behaviour under cyclic load and, as a consequence, a different...
-
Size effect in concrete beams under bending – influence of the boundary layer and the numerical description of cracks
PublicationIn the paper the size effect phenomenon in concrete is analysed. The results of numerical simulations of using FEM on geometrically similar un-notched and notched concrete beams under bending are presented. Concrete beams of four different sizes and five different notch heights under three-point bending test were simulated. In total 18 beams were analysed. Two approaches were used to describe cracks in concrete. First, eXtended...
-
Crack identification using wavelets on experimental staticdeflection profiles
PublicationArtykuł prezentuje metodę lokalizacji uszkodzeń w belce wspornikowej za pomocą transformaty falkowej statycznej linii ugięcia. Efektywnośc proponowanej techniki jest sprawdzona na podstawie badań eksperymentalnych. Do pomiaru statycznej linii ugięcia proponuje się metodę fotogrametryczną.
-
Numerical assessment of the fatigue crack propagation in ship structuraldetails.
PublicationPrzedstawiono podejście teoretyczne pozwalające na modelowanie rozwoju pęknięcia w konstrukcji kadłuba okrętu. Omówiono założenia i procedurę realizacyjną. Pokazano wyniki badań rzeczywistych modeli konstrukcji kadłuba-skrzyżowanie wiązań ramowych o jednakowej wysokości. Dokonano porównania i krytycznej analizy wyników uzyskanych na drodze teoretycznej z wynikami badań rzeczywistych.
-
Genetic algorithm for fatique crack detection in Timoshenko beam.
PublicationW pracy przedstawiono metodę detekcji peknięć zmęczeniowych w początkowej fazie ich rozwoju. Algorytm detekcji wykorzystuje metodę algorytmów genetycznych połączoną z metodą gradientową. Funkcja celu oparta została o zmiany w propagujacej fali sprężystej.
-
On stress singularity near the tip of a crack with surface stresses
PublicationIn the framework of the simplified linear Gurtin–Murdoch surface elasticity we discuss a singularity of stresses and displacements in the vicinity of a mode III crack. We show that inhomogeneity in surface elastic properties may significantly affect the solution and to change the order of singularity. We also demonstrate that implicitly or explicitly assumed symmetry of the problem may also lead to changes in solutions. Considering...
-
Crack Resistance of Asphalt Concrete Subjected to Environmental Factors
PublicationThe paper presents an analysis of the influence of environmental factors on the cracking susceptibility of asphalt concrete resulting in a change in the durability of asphalt pavement. In order to assess the phenomenon, laboratory tests were carried out taking into account the destructive effects of moisture, freeze-thaw cycle and long-term ageing. The influence of both factors occurring simultaneously was also verified. Due to...
-
Analysis of geometrical layout of tram tracks based on the railway methods
Publication -
Optical fibers and photonics applications: topical tracks at Wilga Conferences
Publication -
Correction of determined coordinates of railway tracks in mobile satellite measurements
Publication -
Correction of determined coordinates of railway tracks in mobile satellite measurements
PublicationThis article examines one of the basic issues related to the technique of mobile satellite measurements in railway tracks. This problem concerns the correction of the determined coordinates of the track centerline. The need to perform this operation results from the GNSS receivers positioning at a certain height above the level of the existing track axis, leading to longitudinal and lateral shifts of antennas. The key problem here...
-
Calculations of notch stress factor of a thin-walled spreader bracket fillet weld with the use of a local stress approach
PublicationPresence of geometric notches in welded joints causes concentration of strains and stresses, therefore reducing fatigue strength of such joints. This article presents an analysis of stress concentrations in a fillet weld of a spreader mounting bracket on a small sailing yacht. The aim of this article is to direct the attention of designers, manufacturers and regulatory bodies to issues of fatigue cracks that form in brackets fastening...
-
Comparison of strain results at a laser weld notch obtained by numerical calculations and experimental measurements
PublicationIn the development of ship structures applying new materials and it’s purposeful placement play an important role. During the last years, especially in a construction of ro-ro type vessels, the usage of novel sandwich structures in cargo decks is profitable. Steel sandwich panel is an innovative solution which at a todays state of development can be used for the construction of any members not taking part in a global bending of...
-
Turning ability of hydrofoil crafts
PublicationPrzedstawiono metodę pozwalającą wyznaczać średnicę taktyczną, kąt przechyłu i kąt dryfu oraz siłę poprzeczną na sterze podczas ustalonej cyrkulacji wodolotu. W tym celu opracowano układ równań opisujących ruch wodolotu w płaszczyźnie poziomej. Współczynniki równań są wyznaczane na podstawie głównych parametrów geometrycznych jednostki oraz płatów. Przeprowadzono także szereg obliczeń dla różnych konfiguracji płatów oraz zespołu...
-
Crack identification using wavelets on experimental static deflection profiles
Publication -
Crack Mouth Opening Displacement for EH36 Shipbuilding Steel Measurements
PublicationThe dataset titled EH36 steel for shipbuilding (plate thicnkness 50mm) - CMOD - force record, a0/W = 0.6 contains CMOD (Crack Mouth Opening Displacement) - Force record which is the base for evaluation of fracture toughness of structural steel. Bend specimens witch Bx2B section (B= 50mm), and relative initial crack length a0 / W = 0.60 were used. The test was carried out at ambient temperature in accordance to ISO 12135 standard....
-
NONLINEAR VIBRATION ANALYSIS OF BEAM AND PLATE WITH CLOSED CRACK: A REVIEW
PublicationThe effect of nonlinearity is high sensitivity in damage detection, especially for closed cracks and delamination. This review illustrates the results of several researchers dealing with nonlinear effects caused by the closure of cracks in the structure, i.e., beam and plate structures. Early detection of damage is an important aspect for the structure and, therefore, continuous progress is being made in developing new and effective...
-
Longitudinal wave propagation. Part II—Analysis of crack influence
Publication -
Longitudinal wave propagation. Part II, Analysis of crack influence
PublicationW pracy analizowano wpływ pęknięć zmęczeniowych na propagacje fali wzdłużnej w prętach. Opracowano nowe typy element ów spektralnych oparte na teorii elementarnej, Love'a, Mindlina i trójpostaciowej.
-
Mesoscopic simulations of crack propagation in concrete using cohesive elements
PublicationThe paper presents results of two-and three-dimensional meso-scale simulations of fracture in notched concrete beams subjected to three-point bending test. Concrete was assumed as a 3-phase material composed of aggregate grains placed in the cement matrix with Interfacial Transitional Zones (ITZs) between then. In 2D simulations macro-voids were also taken into account. The particle distribution was taken from real concrete beams...
-
Fluorescent imaging of heavy charged particle tracks with LiF single crystals
Publication -
Luminescent properties of LiF crystals for fluorescent imaging of nuclear particles tracks
Publication -
The analysis of tram tracks geometrical layout based on Mobile Satellite Measurements
PublicationIn this article, the results of the research in a field of which uses active global navigation satellite system (GNSS) geodetic networks for the inventory of geodetic geometric tram tracks are presented. The applied measurement technique has been adapted for the designing of the geometric layout of tram tracks. Several configurations of receivers and settings of an active GNSS networks with the objective to increase the accuracy...
-
Fatigue life improvement using low transformation temperature weld material with measurement of residual stress
PublicationWelding processes often produce high levels of tensile residual stress. Low transformation temperature (LTT) welding wires utilise phase transformation strains to overcome the thermal contraction of a cooling weld. In this paper, the residual stress within each weld was quantified using the milling/strain gauge method, being the strain change measured as the weldment was milled away. The fatigue tests were conducted under uniaxial...
-
Designate CTOD Heat Affected Zone of butt weld, Report No: WOiO/II/76/2013
PublicationTypical (normative) testing of materials and/or welded joints do not answer on all questions about material or welded joint properties. In ship building and off-shore sectors, many strucures requires materials and joint with higher than typical fatigue resistance. Imact tests, which are carried out during welding technology qualification, gives answer about ductility, CTOD tests results about material or welded joint ability...
-
Effect of the Post-Weld Surface Condition on the Corrosion Resistance of Austenitic Stainless Steel AISI 304
PublicationSurfaces of welded elements made of corrosion-resistant (stainless) steels develop temper colours. The removal of thickened oxide layers off steels exposed to temperatures below 300°C is necessary and entails the restoring of high corrosion resistance of the stainless steel. The article presents tests concerned with the effect of a method applied to remove post-weld temper on the corrosion resistance of austenitic stainless steel...
-
P92 steel and inconel 617 alloy welds joint produced using ERNiCr-3 filler with GTAW process: Solidification mechanism, microstructure, mechanical properties and residual stresses
PublicationThe objective of the current study was to analyse the microstructure, mechanical characteristics, and residual stresses of a dissimilar welded joint (DWJ) made of P92 steel and the Inconel alloy 617 (IN617) using the gas tungsten arc welding (GTAW) method. The ERNiCr-3 filler was selected to produce the conventional V groove (VG) and narrow V groove (NVG) butt joint. The filler deficient zones in the weldments, such as the filler...
-
Comparison of low-temperature cracks intensity on pavements with high modulus asphalt concrete and conventional asphalt concrete bases
PublicationHigh modulus asphalt concrete (HMAC) base courses provide very good resistance to rutting and fatigue but they can increase the risk of low-temperature cracking as compared with conventional asphalt concrete (AC). The article presents the comparison of these two road materials in terms of low-temperature cracking. The statistical method based on the ordered logistic regression model was used. The analysis was based on results of...
-
Quantitative assessment of the influence of tensile softening of concrete in beams under bending by numerical simulations with XFEM and cohesive cracks
PublicationResults of the numerical simulations of the size effect phenomenon for concrete in comparison with experimental data are presented. In-plane geometrically similar notched and unnotched beams under three-point bending are analyzed. EXtended Finite Element Method (XFEM) with a cohesive softening law is used. Comprehensive parametric study with the respect to the tensile strength and the initial fracture energy is performed. Sensitivity...
-
Track-to-track fusion in tracking of multiple targets in clutter - a comparative study.
PublicationPrzedstawiono i porównano algorytmy rozproszone wyznaczania trajektorii obiektów dynamicznych na podstawie danych z wielu źródeł. Rozważono przypadek, w którym dane dotyczące pozycji obiektów są zakłócone przez dodatkowe fałszywe wykrycia niezwiązane z obserwowanymi obiektami. Algorytmy rozproszone i centralne to dwie podstawowe klasy algorytmów służące do wyznaczania trajektorii obiektów dynamicznych na podstawie danych z wielu...
-
Detection of Closing Crack in Beam Based on Responses Induced by Harmonic Excitation
PublicationThe non-linear contact model was chosen to simulate the closed crack in the cantilever beam. The study examines the shape and characteristics of the phase diagram of a cantilever beam with closed cracks. It investigates how various crack properties influence the geometry of the phase diagram and proposes a method for identifying cracks based on their features. The area of each closed curve in the phase diagram is determined using...
-
Geometry of cycling track
PublicationThe paper describes the problems related to shaping of the geometry of the cycling track. The method of selection of the angle at the track curve is presented. Issues related to the selection of the appropriate transition curve and the superelevation section along the transition curve are presented. Reference to the recommendations presented in the literature and scientific papers has been made. Special attention...
-
Impedance monitoring of fuel cell stacks
Publication -
Determination of CWR track's durability characteristics
PublicationW pracy przedstawiono wyniki badań nad wyznaczaniem sił osiowych w szynie kolejowej z zastosowaniem metody wymuszonych przemieszczeń poprzecznych. Badania przeprowadzone na stacjonarnym stanowisku badawczym wykazały, że siłę podłużną w szynie można znacznie dokładniej określić na podstawie zmiany nie pionowej, lecz poziomej siły poprzecznej. Pozwoliło to właściwie ukierunkować prace nad określaniem sił osiowych w szynach toru...
-
Impedance monitoring of fuel cell stacks
PublicationThis paper presents an innovative, electrochemical impedance method for monitoring of electrochemical behaviour of a multi-cell, direct methanol fuel cell (DMFC) device. This method not only provides classical voltage changes at successive cells but also allows their detailed impedance behaviour to be presented. Impedance characteristics of individual cells within a fuel cell stack (depending on actual operating conditions) are...
-
Photos and rendered images of LEGO bricks
PublicationThe paper describes a collection of datasets containing both LEGO brick renders and real photos. The datasets contain around 155,000 photos and nearly 1,500,000 renders. The renders aim to simulate real-life photos of LEGO bricks allowing faster creation of extensive datasets. The datasets are publicly available via the Gdansk University of Technology “Most Wiedzy” institutional repository. The source files of all tools used during...
-
Analysis of Ceramic Elements with Ring-Crack Defects in Lubricated Rolling Contact
PublicationThe properties of ceramics, specifically low density, high hardness, high temperature capability and low coefficient of thermal expansion are of most interest to rolling element manufacturers. Surface ring cracks on lubricating rolling contact fatigue failure has been studied using numerical fracture analysis. Such cracks are very often found on ceramic bearing balls and decrease fatigue life rapidly. The numerical calculations...
-
Crack Mouth Opening Displacement for EH36 Shipbuilding Steel Measurements Dataset
PublicationThe dataset titled EH36 steel for shipbuilding (plate thickness 50 mm) – CMOD – force record, a0/W=0.6 contains a CMOD (Crack Mouth Opening Displacement) – Force record which is the base for evaluation of the fracture toughness of structural steel. Bend specimens with a Bx2B section (B = 50 mm), and relative initial crack length a0/W=0.60 were used. The test was carried out at ambient temperature in accordance with the ISO 12135...
-
Assessment of crack resistance of ship steels according to SEP 1390 standard
PublicationThe aim of the study was to evaluate the weldability of E36 nd NVE-36 steels by bending test according to SEP 1390. In the case of the specimen from E36 steel 9 external cracks were found, 5 of which were stopped in the fusion line and 4 in heat affected zone. In the case of the specimen from NVE-36 steel 8 external cracks were found, 4 of which were stopped in the fusion line and 4 in heat affected zone. Results of bending test...
-
Detection and size estimation of crack in plate based on guided wave propagation
PublicationThe paper presents results of the comprehensive theoretical and experimental investigation of crack detection in metallic plate using guided wave propagation. The main aim of the paper is to develop the novel method which would allow for linear crack size estimation with the use of minimal number of the transducers. In general, there exists the relation between length of the propagation path and the wave amplitude value. However,...
-
Tyre/road noise measurements on ISO tracks using the modified CPX method
PublicationTyre rolling noise test method specified in the UNECE Regulation 117 is directly used in the Tyre Labelling Directive. Noise level specified on EU Tyre Label of each new tyre available on the European market was determined based on vehicle coast-by noise measurements performed on the standard reference road surface proscribed in the ISO 10844:2014. Available data from investigations by the vehicle and tyre industry and results...
-
Tyre/road noise measurements on ISO tracks according to the UNECE Regulation 117
PublicationWithin the Polish-Norwegian research project ELANORE, a limited Round Robin Test has been performed on 3 ISO tracks in Northern Europe. The basic objective of the project is to improve the EU directive on labelling of tyres for noise and rolling resistance, and this directive is based on the measurement procedures defined in the UN ECE Reg.117. The same test car, test tyres and measurement equipment as well as personnel were used...
-
Accuracy assessment of mobile satellite measurements in relation to the geometrical layout of rail tracks
PublicationThe paper presents the campaigns of mobile satellite measurements, carried out in 2009–2015 on the railway and tram lines. The accuracy of the measurement method has been analysed on the basis of the results obtained in both horizontal and vertical planes. The track axis deviation from the defined geometric shape has been analysed in the areas clearly defined in terms of geometry, i.e. on the straight sections and sections with...
-
Selecting wells for an optimal design of groundwater monitoring network based on monitoring priority map: A Kish Island case study
PublicationThis paper presents a novel approach, i.e. a combination of gamma test and monitoring priority map, for optimal design of groundwater monitoring network (GMN) by considering the cumulative effects of industries, human activities, and natural factors on the groundwater quality. The proposed method was successfully applied to design an optimal network for groundwater salinity monitoring on Kish Island, Persian Gulf. The priority...
-
The Impact of Homogeneity of High Modulus Asphalt Concrete Layer on Low-Temperature Cracking
PublicationDuring winter season of 2012 numerous transverse cracks developed in high-modulus asphalt concrete (HMAC) base of newly constructed motorway. Pavement cracked both in transverse joint locations and in the area between them. Research which was conducted during investigation of the causes and mechanisms of cracking consisted of: field examination, laboratory testing of specimens cored out of the existing pavement, computational analyses...
-
On the Application of Magnetoacoustic Emission for a Nondestructive Assessment of the Post Welding Heat Treatment of High Chromium Steel Weld Seams
PublicationThe paper analyses the possibility of post weld heat treatment (PWHT) quality assessment with the help of magnetoacoustic emission (MAE) signal measurements. Two welded superheater tubes, made of high chromium VM12 steel, were analysed—as welded and heat treated one. The analysed sample in the as welded state exhibited significantly higher hardness, accompanied by a big difference in the MAE signal intensity (of order of about...
-
Activated Tungsten Inert Gas Weld Characteristics of P91 Joint for Advanced Ultra Supercritical Power Plant Applications
PublicationActivated Tungsten Inert Gas (A-TIG) welding, a variant of tungsten inert gas (TIG) welding, was used for welding P91. In Generation IV power plants, P91 welds are prone to premature failure due to the presence and formation of brittle phases and creep at high temperatures. When performing A-TIG welding, the flux composition plays a role in the reversal of the Marangoni flow in the weld pool, which ultimately determines the level...
-
ICHNOS-AN INTERNATIONAL JOURNAL FOR PLANT AND ANIMAL TRACES
Journals -
Effect of Pendolino high-speed rail on the structure of buildings located the proximity of the railway tracks
PublicationThe following research focuses on the dynamic analysis of the impact of the high-speed train inducted vibrations on the structures located near railway tracks. The office complex chosen as the subject of calculations is located in the northern part of Poland, in Gdańsk, in the proximity of Pendolino, the high speed train route. The high speed trains are the response for the growing needs for more efficient railway system. However...