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1

Analysis of the linear expansion coefficient of S355J2 and C45 steel specimens welded by MIG, MMA and TIG techniques

Kud Bartłomiej, Fejkiel Romuald

Advances in Mechanical and Materials Engineering

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2026

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Vol. 43, nr 1

179--189

EN

Knowledge of the linear expansion coefficient of steel is crucial for ensuring the safety, durability, and proper functioning of welded structures. The aim of this study is to investigate the coefficient of linear expansion of S355J2 structural steel and C45 carbon steel, welded using various techniques: metal inert gas welding, tungsten inert gas welding and manual metal arc welding. Linear expansion tests of steel samples were conducted using a dilatometer. The results allowed for an assessment of the effect of the welding technique and the chemical composition (carbon content) of the steel on the thermal properties of the test materials. The reference samples (materials in as-received state) achieved the highest level of thermal expansion. All welding techniques reduced the temperature-induced elongation, with the magnitude of this effect dependent on the welding technique used. The results have practical implications for the design of structural components exposed to variable temperature conditions. Understanding the effect of individual welding techniques on the properties of S355J2 and C45 steels can support the selection of material welding technologies where dimensional stability is an important quality parameter.

PL

Znajomość wartości współczynnika rozszerzalności liniowej stali ma kluczowe znaczenie w zapewnieniu bezpieczeństwa, trwałości i poprawnego działania konstrukcji spawanych. Celem niniejszej pracy jest zbadanie współczynnika rozszerzalności liniowej stali konstrukcyjnej S355J2 oraz stali węglowej C45, spawanych różnymi metodami: elektrodą topliwą w osłonie gazów obojętnych, nietopliwą elektrodą wolframową w osłonie gazów obojętnych oraz metodą łukowego spawania elektrodą otuloną. Badania rozszerzalności liniowej przeprowadzono z wykorzystaniem dylatometru. Wyniki pozwoliły na ocenę wpływu metody spawania oraz składu chemicznego (zawartości węgla) stali na właściwości termiczne badanych materiałów. Próbka referencyjna (materiał w stanie dostawy) osiągnęła najwyższy poziom rozszerzalności cieplnej. Wszystkie zastosowane metody spawalnicze prowadziły do zmniejszenia wydłużenia wywołanego zmiana temperatury, przy czym skala tego efektu była uzależniona od użytej techniki spawania. Uzyskane wyniki mają praktyczne znaczenie w kontekście projektowania elementów konstrukcyjnych narażonych na zmienne warunki temperaturowe. Zrozumienie wpływu poszczególnych metod spawania na właściwości stali S355J2 i C45 może wspomagać wybór technologii łączenia materiałów tam, gdzie stabilność wymiarowa jest ważnym parametrem jakościowym.

2

Influence of corrosion on the fatigue resistance of a carbon steel with Ti and Cr nitrides based coatings

Vicen Martin, Zatkalíková Viera, Bokůvka Otakar, Nový František, Belan Juraj, Nikolic Ružica

System Safety : Human - Technical Facility - Environment

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2025

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Vol. 7, iss. 1

295--304

EN

The quality of components and structures is directly related to degradation processes such as corrosion and fatigue that are concomitant phenomena during their operation. One of the options for increasing the quality of components and structures is the use of appropriate surface coating. In this paper is presented an experimental investigation of the corrosion influence on the fatigue resistance of the carbon steel with coatings based on Ti and Cr nitrides. The experimental work included determination of the chemical composition of the base material, heat treatment, microstructure evaluation, mechanical properties measurement, coating depositions, corrosion test and the fatigue tests by rotation bending of the deposited layers. The corrosion and fatigue tests have shown that the coating provides improvement of the corrosion resistance and that there was no reduction of the fatigue resistance.

3

Structure and mechanical properties of cermet Ni-Al/MSZ thick coating prepared by flame spraying technique

Saleh Mahmood M., Khemakhem Hamadi, Jassim Ismel K., Al-Saqa Read Hashim

Ochrona przed Korozją

|

2024

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nr 1

9--14

EN

The aim of this study was to obtain a thick protective cermet coating on API 5L (carbon steel) pipes, used in the oil industry. A new method involving flame spray coating has been selected to produce thick ceramic-metal coatings of Ni-Al/MgO-ZrO2 under optimal spraying parameters. Structural properties were measured by X-ray diffraction (XRD). Morphology was determined by means of scanning electron microscopy (SEM). The elemental composition in the cermet coating was confirmed by energy dispersive spectroscopy (EDS). Deposition efficiency was found to be an important factor as demonstrated by adhesion force results obtained using the pull-out tensile test. The results show that the best spray distance is 20 cm, as it ensures good interaction between the layers, a high adhesion force value of 8.4 MPa, a uniform microstructure, low porosity, a hardness of 166.4 HV, and a coating thickness of approximately 1.85 mm. X-ray results clearly show that the cermet coating consists of numerous phases, such as tetragonal (T), monoclinic, and face center cubic (FCC). SEM images revealed that the typical particle-containing microstructures consisted of spherical shapes with elongated agglomerations. Finally, based on the results obtained, it can be concluded that flame spray coating provides a significant improvement in performance.

PL

Celem pracy było uzyskanie grubej ochronnej powłoki cermetalowej na rurach API 5L (ze stali węglowej), stosowanych w przemyśle naftowym. Wybrano nową metodę natryskiwania płomieniowego w celu wytworzenia grubych powłok ceramiczno-metalowych Ni-Al/MgO-ZrO2 przy optymalnych parametrach natryskiwania. Właściwości strukturalne zostały zmierzone za pomocą dyfrakcji rentgenowskiej (XRD). Morfologię określono za pomocą skaningowej mikroskopii elektronowej (SEM). Skład pierwiastkowy powłoki cermetalowej ustalono, używając spektroskopii dyspersji energii (EDS). Stwierdzono, że wydajność osadzania jest ważnym czynnikiem, o czym świadczą wyniki pomiaru siły adhezji uzyskane w próbie rozciągania. Z badań wynika, że najlepsza odległość natryskiwania wynosi 20 cm – zapewniona jest wówczas dobra interakcja między warstwami, wysoka wartość siły adhezji: 8,4 MPa, jednolita mikrostruktura, niska porowatość, twardość wynosi 166,4 HV, a grubość powłoki ok. 1,85 mm. Badania rentgenowskie pozwoliły ustalić, że powłoka cermetalowa składa się z wielu faz: tetragonalnej (T), jednoskośnej i FCC. Obrazy SEM ujawniły, że typowe mikrostruktury zawierające cząstki składały się z kulistych struktur tworzących wydłużone aglomeracje. Na podstawie uzyskanych wyników można stwierdzić, że zastosowana metoda natryskiwania płomieniowego zapewnia znaczną poprawę właściwości ochronnych.

4

Study on the microstructure and technological properties of clad plates made of steels S235jR and X20Cr13 and S235jR and X5CrNi18-10 after hot rolling

Walnik Bartłomiej, Woźniak Dariusz, Adamczyk Mariusz, Palus Rafał, Bagińska Aleksandra

Materials Science and Welding Technologies / Technologie Materiałowe i Spawalnicze

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2024

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Vol. 68, No. 3

art. no. 1

EN

The article presents the results of physical experiments consisting in the rolling of layered plates (clad plates). The experiments involved two types of two-layered flat bars, i.e. S235JR and X20Cr13 as well as S235JR and X5CrNi18-10. The experiment resulted in the development of a technology for the fabrication of layered flat bars made of structural steel S235JR, corrosion-resistant steel X20Cr13 and austenitic acid-resistant steel X5CrNi18-10. Microstructural observations were performed using a light microscope (LM) and a scanning electron microscope (SEM). The observations revealed the possibility of obtaining permanent joints through hot rolling and the possibility of applying steel grades S235JR, X20Cr13 and X5CrNi18 in the fabrication of layered plates.

PL

W artykule omówiono wyniki fizycznych eksperymentów walcowania blach warstwowych. Eksperymenty wykonano na dwóch rodzajach płaskowników dwuwarstwowych S235JR – X20Cr13 i S235JR – X5CrNi18-10. Wynikiem eksperymentów było opracowanie technologii wytwarzania płaskowników o budowie warstwowej, złożonych ze stali konstrukcyjnej S235JR oraz ze stali odpornej na korozję X20Cr13 i stali kwasoodpornej austenitycznej X5CrNi18-10. Badania mikrostruktury przeprowadzono przy użyciu techniki mikroskopii świetlnej i skaningowej mikroskopii elektronowej, SEM. Wyniki pracy wskazują, że dobrane parametry walcowania na gorąco pozwoliły na wytworzenie trwałego połączenia pomiędzy blachami w wyniku ich walcowania na gorąco i na możliwość zastosowania stali z gatunków S235JR, X20Cr13 i X5CrNi18 na blachy warstwowe.

5

Optimization of mechanical performance in arc and TIG welding joints via advanced thermal treatment techniques

Ali Aenas L., Obaid Zuhair H.

Archives of Engineering Knowledge

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2024

|

T. 10, Nr 1

109--113

EN

Welding is one of the most important industrial processes, and many techniques have been developed to achieve efficient and low cost welding of various metals. This research aims to compare two common welding methods, conventional arc welding (Arc Welding) and shielding gas arc welding (TIG Welding), when applied to low carbon steel. Mechanical tests were conducted, including tensile testing and hardness measurement, in addition to microstructure analysis through photographic documentation. The results showed that the maximum tensile strength of the arc-welded sample was 25.5% higher than that of the unwelded metal, while the tensile strength of the TIG-welded sample was 9.5% lower. In terms of hardness, the highest value of TIG welding was about 300 HV, compared to 250 HV for conventional arc welding, indicating that TIG welding produces a microstructure with higher hardness but at the expense of tensile strength. It was also found that post-welding heat treatment improved the mechanical properties of both methods, enhancing their strength and operational characteristics. These results provide important guidance for selecting the appropriate welding method based on mechanical requirements, with arc welding being preferred when high tensile strength is required, while TIG welding is more suitable for applications requiring higher hardness and greater corrosion resistance.

6

Strong strain‑hardening capability in plain carbon steel through cold rolling and heat treatment of lamellar structure

Talebi Fatemeh, Jamaati Roohollah, Hosseinipour Seyed Jamal

Archives of Civil and Mechanical Engineering

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2024

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Vol. 24, no. 1

art. no. e44, 2024

EN

In the current research, strong strain-hardening capability in 1045 carbon steel was achieved by cold rolling and heat treatment of the lamellar structure. After 60% cold rolling, the proeutectoid ferrite and pearlite were severely elongated along the rolling direction. Cementite layers with brittle nature were fragmented under the action of stress and also by shear band formation during rolling. The lamellar heterogeneous microstructure of the heat-treated samples was formed by the proeutectoid ferrite as the soft domain and the pearlite as the hard domain. Increasing the heat treatment duration promoted the spheroidization transformation of cementite, and the spheroidization degree of cementite increased. With the increase in the time of heat treatment, the number of recrystallized grains is increased. Heat treatment led to weakening the deformation texture (⟨100⟩‖ND or θ fiber) and strengthening the recrystallization texture (⟨110⟩‖ND or ζ fiber). The heat-treated steels revealed an average microhardness value much higher than its macrohardness due to changes in the texture of ferrite grains. Heat treatment decreased the strength and hardness, and increased the ductility and toughness of steel compared to the cold-rolled sample owing to the annihilation of dislocations and the strengthening transition from strain hardening to grain refinement. The heat-treated samples exhibited a wider range of uniform plastic deformation and a larger strain hardening rate than the cold-rolled sample owing to the occurrence of the recovery of strain hardening rate phenomenon. The appropriate collocation of the fine spherical cementite and the soft/hard domains (with a large difference in mechanical properties) was beneficial to obtaining excellent strength-ductility balance in plain medium carbon steel. After heat treatment, the extent of ductile fracture considerably increased. With increasing the time of heat treatment from 1 to 3 h, the number of lamellar dimples decreased owing to the creation of more fine spherical cementite

7

Effects of incorporation of nanotitania in magnesium phosphate cement for the protection of carbon steel in harsh environments

Sujitha V. S., Ramesh B., Xavier Joseph Raj

Archives of Civil and Mechanical Engineering

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2024

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Vol. 24, no. 2

art. no. e79, 2024

EN

Corrosion is a major challenge to ensuring the durability and structural integrity of steel structures, particularly under harsh environmental conditions. In this work, we explored the possibility of incorporating nanotitania (TiO2) into magnesium phosphate cement (MPC) coatings to improve the corrosion resistance of low-carbon steel (LCS). Magnesium phosphate cement (MPC) has great potential to replace conventional organic coatings because of its corrosion resistance and sustainability. Titanium dioxide (TiO2) nanoparticles are included in the MPC coating to protect steel structures from corrosion because of their effectiveness in preventing them from decreasing the lifespan of steel. The material characterization of the MPC/TiO2 coatings was conducted using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) methods. Tafel polarization and electrochemical impedance spectroscopy (EIS) were used to assess the corrosion resistance of the coated and uncoated samples in a 3.5% NaCl solution. EIS measurements revealed that the MPC/TiO2 coatings, particularly those containing 10% TiO2, exhibited superior anti-corrosion properties. The resistance (Rcoat) measured for this coating was 1.22E10 Ω cm2, and the charge transfer resistance (Rct) reached 1.50E12 Ω cm2, demonstrating remarkable corrosion protection. The accelerated corrosion test proves that the inclusion of 10% nanotitania in the MPC controls the delamination of the coating. Additionally, the adhesion strength of 18.1 MPa for the MPC/10TiO2 coating confirms the durability of the coating. Only a small percentage of weight loss and adhesion loss were observed after 28 days of immersion in a corrosive NaCl environment, demonstrating the long-term durability of the MPC/TiO2 coatings. The findings of this study indicate that adding 10% TiO2 to MPC coatings has enormous potential for improving the corrosion resistance of LCSs. This cementitious coating material offers an effective way to reduce early oxidation in steel buildings, making it a useful tool in construction projects intended to ensure the prolonged lifespan of LCS components.

8

Application of regression models on the prediction of corrosion degradation of a crude oil distillation unit

Varbai Balázs, Wéber Richárd, Farkas Balázs, Danyi Péter, Krójer Antal, Locskai Roland, Bohács György, Hős Csaba

Advances in Materials Science

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2024

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Vol. 24, nr 1(79)

72--85

EN

The crude distillation unit is the most critical elements in the refining process. Moreover, most of the equipment in the distillation unit are made of general carbon steels. Data analysis models, machine learning techniques can predict corrosion degradation rates. We used Pearson’s correlation coefficient and multiple linear regression, to predict the impact of process parameters. Altogether, we have analysed 84 channels of technological parameters, and 22 different types of crude oils. Among the corrosion agents, the chloride content strongly affected the weight loss of coupons, where the highest coefficient was 0.68. The most influential parameter is found to be the pH value. Thus, an estimation method of the pH value is set up to predict the corrosion degradation rate. The regression correlation for estimating the pH value is 0.53 if the corrosion agents are not used, which can be improved to 0.76 if the corrosion agents are also used in the regression analysis.

9

Influence hot plastic deformation on the structure and properties of carbon steel of the railway wheel

Vakulenko Igor, Plitchenko Sergey, Bolotova Dariy, Asgarov Khangardash

Zeszyty Naukowe. Transport / Politechnika Śląska

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2023

|

z. 121

257--266

EN

The study is devoted to the explanation of the influence of hot plastic deformation on the properties of railway wheels. The shape of individual elements of the wheel provides for a different degree of hot compression, which determines the mechanism for the development of the recrystallization at austenite. With a decrease in the degree of the hot deformation, a certain proportion of grains with a low energy of linear stretching are formed in austenite. As a result, of the low mobility of such boundaries, the likelihood of preservation of part of the substructural state of the austenite increases, which should affect the formation of a colony of perlite during the cooling of the carbon steel. Against background preservation and a dependence of strength properties on the dispersion of the pearlite colony, the appearance in austenite of grain boundaries with a low energy of linear tension leads to a qualitative change in the plastic properties of railway wheel steel. The increase in plasticity of carbon steel with an increase in dispersion of the pearlite colony is due to a decrease in the effect of solid solution hardening and an increase in the role of the ferrite-cementite interface in the development processes of strain hardening carbon steel. The results obtained can be useful for improving the technology of manufacturing all-rolled railway wheels.

10

Influence structure on the plasticity of carbon steel of the railway wheel rim in operation

Vakulenko Igor Alex, Vakulenko Leonid, Bolotova Dariy, Kurt Bulent, Asgarov Hangardash, Çölova Ömer

Zeszyty Naukowe. Transport / Politechnika Śląska

|

2022

|

z. 115

183--192

EN

When simulating the operating conditions of the rim of a railway wheel, an analysis of change in the structural state from the possible degree of plastic deformation and the heating temperature of steel near the rolling surface was carried out. The development processes of spheroidization and coalescence of cementite during heating of the cold-worked steel change its ability to strain hardening. Substructure changes during heating to temperatures of 500-550°C deformed steel are accompanied by a simultaneous decrease in its ability to strain hardening and the level of plasticity. When heated above 500-550°C, the development of ferrite recrystallization processes provides a gradual transition of the metal from substructure hardening to hardening from grain boundaries with large angles of disorientation. It is shown that regardless of the nature of the main structural element, the ability of steel to strain hardening and the level of plasticity after heating are related by a proportional relationship.

11

Joining of carbon steel AISI 1006 to aluminum alloy AA6061-T6 via friction spot joining technique

Ridha Munaf Hashim, Saad Mursal Luaibi, Abdullah Isam Tareq, Barrak Osamah Sabah, Hussein Sabah Khammass, Hussein Abbas Khammas

International Journal of Applied Mechanics and Engineering

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2022

|

Vol. 27, no. 4

1--12

EN

This work aims to join sheets of carbon steel to aluminum alloy AA6061. A lap joint arrangement was used with a joint lap area of dimensions *25 25 mm . The joining procedure was carried out using a rotating tool of 10 mm shoulder diameter. Three process parameters, with three levels for each parameter, were selected to investigate their effects on joints quality. The parameter’s levels for each experiment were designed using the design of the experiment method (DOE). The results indicated that the two materials were joined by a mechanical interlock at an interface line, without formation of intermetallic compounds. The shear force of the joint reached an ultimate value of .4 82kN . The shear force of the joint improved by increasing plunging depth of the tool. Samples of minimum shear force value failed by a pull-outing aluminum metal from the carbon steel specimen. Samples of higher shear force value exhibited a shear mode of fracture. Increasing the rotating speed and decreasing pre-heating increased the process temperature.

12

Friction spot lap joining of aluminum alloy AA6061 to pre-holed and threaded carbon steel AISI 1006

Ibrahim H. K., Hussein S. K., Jadee K. J.

International Journal of Applied Mechanics and Engineering

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2022

|

Vol. 27, no. 1

67--77

EN

This work addresses to joining aluminum alloy AA6061 to carbon steel AISI 1006 sheets using the friction spot joining technique. The steel sheets were pre-holed and threaded with an internal M6 thread. The joining process was carried out by extruding the aluminum through the steel hole and thread using a rotating tool with friction between the tool and aluminum. Three process parameters were used: pre-heating time, rotating speed and plunging depth of the tool, with four levels for each parameter. The results indicated that the two materials joined by a micro-scale mechanical interlock at an interface line of a width ranged between 0.7 to ~ 2.5 mm. The joint’s shear force reached a minimum and maximum value of 2000 and 2500 N, respectively. The plunging depth was the most effective factor affecting the amount of the extruded aluminum and the joint’s shear force.

13

Model wymiany ciepła w procesie ciągłego odlewania stali z uwzględnieniem lokalnego warunku brzegowego

Rywotycki Marcin, Hadała Beata, Malinowski Zbigniew

Hutnik, Wiadomości Hutnicze

|

2021

|

Vol. 88, nr 3-4

19--22

PL

W pracy przedstawiono obliczenia symulacyjne pola temperatury wykonane dla wlewka płaskiego ze stali węglowej. Modelowano proces ciągłego odlewania pasma o szerokości 1500 mm i wysokości 225 mm. W symulacjach numerycznych założono trzy warianty warunku brzegowego wymiany ciepła. W pierwszym wariancie współczynnik wymiany ciepła w każdej strefie chłodzenia zależał od temperatury powierzchni i gęstość strumienia wody bez uwzględnienia istnienia rolek. Drugi model warunku brzegowego definiował współczynnik wymiany ciepła wokół każdej dyszy natryskowej również bez uwzględnienia wymiany ciepła z rolkami. Ostatnim wariantem obliczeń był model, w którym uwzględniono lokalny współczynnik wymiany ciepła wynikający z zastosowanego układu chłodzenia oraz kontaktu z rolkami podtrzymującymi i ciągnącymi. Analizie poddano pole temperatury otrzymane w wyniku obliczeń dla trzech przyjętych wariantów warunków brzegowych. Warunek brzegowy, który uwzględnia ułożenie dysz oraz rolek pozwolił uzyskać bardziej nierównomierne, bliższe rzeczywistemu pole temperatury. Zastosowanie modelu najbardziej rozbudowanego pozwala z dużą dokładnością wyznaczyć pole temperatury na powierzchni krzepnącego pasma w maszynie COS.

EN

The calculations of ingot temperature field, which was made for carbon steel slabs were presented. The dimension of the ingot was 1500 mm wide and 225 mm high. In the numerical simulations, three models of the boundary condition of the heat transfer were used. In the first one, the heat transfer coefficient in the secondary cooling zones was calculated as a function of surface temperature and water jet density. In the second model the heat transfer coefficient is defined around each spray nozzle. In the first and second model contact with the rolls was neglected. The last variant of the calculations has been done for local heat transfer coefficient (model 2) and the contact with rolls was included. The simu-lation results for three models have been analysed. Model with the boundary condition, which takes into account the position of nozzles and rolls, has given the most accurate results of temperature fields in the continuous casting process. The calculations have been performed using self-developed software which uses the inverse method and FEM.

14

Insights into factors of damage of surface rolling of railway wheels during operation

Aaskerov Hangardas, Vakulenko Igor, Grischenko Nikolaji

Zeszyty Naukowe. Transport / Politechnika Śląska

|

2019

|

z. 105

27--33

EN

The systematization results of microstructure studies of carbon steel has made it possible to explain the mechanism of formation of certain damages to the rolling surface of railway wheels during operation. The evaluation ability of metal to strain hardening was used to explain the nature of the influence compactly located non-deformable dispersed particles on the strength properties steel during cold plastic deformation. In the process of the interaction of a railway wheel with a rail, successively occurring heterogeneities in the distribution of the plastic flow metal are one of the main reasons for the formation of defects on the rolling surface of the wheel.

15

Laser forming of steel tubes

Radek Norbert, Kurp Piotr, Pietraszek Jacek

Technical Transactions

|

2019

|

Vol. 116, iss. 1

223--229

EN

The paper presents a study on microstructure and microhardness changes obtained in the spun carbon steel tube after shaping by a laser beam. The surface of a pipe was machined circumferentially using a 1500 W CO2 laser beam at various diameters (distance from the focus). As a result, plastic deformations such as convex and narrowing shape changes were observed. The conducted research, including microhardness measurements, shows that, in comparison to the unprocessed material, the microstructure was significantly changed, both in the convex and narrowed layer.

PL

W pracy przedstawiono badania zmian mikrostruktury i mikrotwardości warstwy wierzchniej wyoblonej i przewężonej rury ze stali węglowej po laserowym kształtowaniu. Powierzchnia rury była skanowana po obwodzie wiązką lasera CO2 o mocy 1500 W przy różnych średnicach (odległościach od ogniska). W efekcie uzyskano odkształcenia plastyczne, takie jak wyoblenie i przewężenie rury. Przeprowadzone badania, w tym pomiary mikrotwardości, wykazują, że mikrostruktura uległa istotnej zmianie w stosunku do materiału rodzimego, zarówno w warstwie wyoblonej, jak i przewężonej.

16

Badania właściwości mechanicznych i mikrostruktury eksperymentalnych blach warstwowych walcowanych na gorąco

Walnik Bartłomiej, Woźniak Dariusz, Adamczyk Mariusz

Hutnik, Wiadomości Hutnicze

|

2019

|

Vol. 86, nr 10

309--314

PL

W artykule przedstawiono wyniki prób walcowania na gorąco blach warstwowych w linii do badań w skali półprzemysłowej (LPS), z zastosowaniem jednego przepustu z gniotem względnym około 40%. Próby technologiczne wykonano na blachach warstwowych, będących połączeniami stali: S235JR, S355J2, 42CrMo4 i X5CrNi18-10. Wykonano próby wytrzymałościowe na zginanie i ścinanie z uzyskanych połączeń. Badania mikrostruktury przeprowadzono przy użyciu mikroskopu świetlnego. Wyniki pracy wskazują na możliwość wytworzenia unikatowych wyrobów łączących w sobie cechy stali z gatunków S235JR, S355J2, 42CrMo4 i X5CrNi18-10 bezpośrednio w procesie walcowania na gorąco.

EN

The article presents the results of experiments of one pass rolling of layered sheets with relative reduction ~40%. The experiments were carried out in the semi industrial line to simulation of hot rolling process (LPS)on layered plates from steels: S235JR, S355J2, 42CrMo4 and X5CrNi18-10. Bending and shearing strength tests were carried out. Microstructure investigation was carried out with the use of a light microscope. The results of the work indicate the possibility of creating unique products composed of different types of steels: S235JR, S355J2, 42CrMo4 and X5CrNi18-10 in hot rolling process.

17

Assessing the condition of the material of pressure vessel after their long-lasting operation in the petrochemical industry using non-destructive acoustic methods and structural stress field analysis

Lyasota Igor, Sarniak Łukasz, Kustra Piotr

Biuletyn Instytutu Spawalnictwa w Gliwicach

|

2019

|

Vol. 63, No. 3

53--60

EN

The article discusses complex tests of an actual pressure vessel after its long-lasting operation in a petroleum distillation system. As a result of exposure to extreme conditions, the structural material of the vessel degraded and corroded significantly. The corrosion damage was identified and imaged using a Phased Array technique-based ultrasonic method. The subsequent stage of investigation involved hydraulic tests and the recording of acoustic emission signals. Stress concentration fields in damaged areas were identified using the FEM-based simulation method. The test results will be used to develop the complex methodology enabling the evaluation of the technical condition of pressure vessels used in the petrochemical industry. The above-named objective constitutes the primary goal of Programme LEADER VII, funded by the National Centre for Research and Development.

PL

Wykonano kompleksowe badania stanowiskowe rzeczywistego zbiornika ciśnieniowego poddanego wieloletniej eksploatacji w instalacji destylacji ropy naftowej. Na skutek pracy w warunkach ekstremalnych materiał elementów konstrukcji urządzenia uległ degradacji oraz zawierał liczne uszkodzenia korozyjne, które zostały zidentyfikowane i odwzorowane za pomocą szczegółowych badań metodą ultradźwiękową z wykorzystaniem techniki Phased Array. Na dalszym etapie badań wykonano próby hydrauliczne z rejestracją sygnałów emisji akustycznej. W celu określenia stref o koncentracji pola naprężeń w obszarach uszkodzeń dodatkowo wykonano symulację metodą elementów skończonych. Wyniki wykonanych badań stanowią bazę do opracowania złożonej metodyki oceny stanu technicznego urządzeń ciśnieniowych przemysłu rafineryjnego – głównego celu projektu badawczego Programu LIDER VII sfinansowanego przez Narodowe Centrum Badań i Rozwoju.

18

Identification of the tensile damage of degraded carbon steel and ferritic alloy-steel by acoustic emission with in situ microscopic investigations

Lyasota Igor, Kozub Barbara, Gawlik Józef

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 1

274--285

EN

The paper presents results obtained from the destructive laboratory investigation conducted on materials from pressure vessels after long-term operation in the refinery industry. Tested materials contained structural defects, which arose from improper heat treatment during steel plate manufacturing. Detailed metallographic and chemical composition tests and static tensile tests were conducted. Next, complex tensile tests were conducted with simultaneous acoustic emission (AE) monitoring while observing microstructural changes by light microscopy. From the laboratory tests, the correlations between the AE signal parameters and material microstructural damage during the tensile tests were developed. The results will be used as a basis of new algorithms for the structural condition assessment of in-service pressure equipment.

19

Structure and properties of the steel railway wheel disc after forced cooling

Vakulenko I., Grischenko N., Vakulenko L., Efremenko V., Proiydak S., Perkov O.

Zeszyty Naukowe. Transport / Politechnika Śląska

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2018

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z. 98

173--180

EN

The technological use of accelerated cooling makes it possible to improve the carbon steel properties of the all-rolled railway wheel disc. The properties’ complex depends on the temperature of the accelerated cooling termination. This is determined by the ratio of the carbon atoms emitted from the supersaturated solid solution to the crystal structure defects and dispersion strengthening from carbide phase particles. If the cooling stops at a temperature above 350°C, the decline rate of the strength properties increases. This is caused by the excessive softening effect of the solid solution breakdown and cementite spheroidization during the processes of dispersion hardening.

20

Model wymiany ciepła w procesie ciągłego odlewania stali z uwzględnieniem lokalnego warunku brzegowego

Rywotycki M., Hadała B., Malinowski Z.

Przegląd Mechaniczny

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2018

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nr 3

40--43

PL

W pracy przedstawiono obliczenia symulacyjne pola temperatury wykonane dla wlewka płaskiego ze stali węglowej. Modelowano proces ciągłego odlewania pasma o szerokości 1500 mm i wysokości 225 mm. W symulacjach numerycznych założono trzy warianty warunku brzegowego wymiany ciepła. W pierwszym wariancie współczynnik wymiany ciepła w każdej strefie chłodzenia zależał od temperatury powierzchni i gęstości strumienia wody bez uwzględnienia istnienia rolek. Drugi model warunku brzegowego definiował współczynnik wymiany ciepła wokół każdej dyszy natryskowej również bez uwzględnienia wymiany ciepła z rolkami. Ostatnim wariantem obliczeń był model, w którym uwzględniono lokalny współczynnik wymiany ciepła wynikający z zastosowanego układu chłodzenia oraz kontaktu z rolkami podtrzymującymi i ciągnącymi. Analizie poddano pole temperatury otrzymane w wyniku obliczeń dla trzech przyjętych wariantów warunków brzegowych. Warunek brzegowy, który uwzględnia ułożenie dysz oraz rolek, pozwolił uzyskać bardziej nierównomierne, bliższe rzeczywistemu pole temperatury.

EN

The calculations of ingot temperature field, which was made for carbon steel slabs were presented. The dimension of the ingot was 1500 mm wide and 225 mm high. In the numerical simulations, three models of the boundary condition of the heat transfer were used. In the first one, the heat transfer coefficient in the secondary cooling zones was calculated as a function of surface temperature and water jet density. In the second model the heat transfer coefficient is defined around each spray nozzle. In the first and second model contact with the rolls was neglected. The last variant of the calculations has been done for local heat transfer coefficient (model 2) and the contact with rolls was included. The simulation results for three models have been analysed. Model with the boundary condition, which takes into account the position of nozzles and rolls, has given the most accurate results of temperature fields in the continuous casting process.