Showing papers in "Journal of Metallic Materials in 2022"

Application of icp-oes spectrometry for determination of high concentrations of silicon in cast iron and steel

Abstract: The study investigates the possibility of applying induced plasma atomic emission spectrometry (ICP-OES) to determine silicon content exceeding 0.5% in iron-based samples. ICP-OES spectrometry requires liquid samples. Solid samples must be dissolved prior to the analysis. Dissolution of some types of steel requires strongly oxidising mixtures of inorganic acids. In such conditions, higher silicon contents tend to form insoluble oxides. Silicon oxides, in the form of amorphous sediment, precipitate on the bottom and walls of laboratory vessels. As a result, silicon determinations are strongly underestimated. The article presents the preparation of iron matrix based solutions for the determination of silicon-high concentrations using ICP-OES spectrometry.

Study on the influence of sheet straightening process on residual stress distribution, mechanical properties and structure of deep-drawing steel sheets

Abstract: The article describes the impact of the stretch levelling process of DC03 and DC04 steel sheets on their quality in terms of further application for products formed in technologies used in the automotive industry. The straightening process was carried out in a demonstration line developed as part of a project carried out by DAR STAL Dariusz Zaława together with the Łukasiewicz Research Network – Institute for Ferrous Metallurgy. The study examined the influence of stretch levelling on waviness and the state of internal stresses of the sheets. It was found that the use of stretch levelling with a controlled elongation value results in obtaining a favourable and stable state of stress in the sheets. No significant influence of the straightening process on the structure and mechanical properties of the sheets was found.

Modelling of material flows in piercing technology

Abstract: The article summarises the modelling of the technological process of Mannesmann piercing in the configuration of the GreatMannesmann rolling mill in the Tube Mill of Třinecké Železárny using the approach of both mathematical modelling and numerical simulation. In accordance with the mathematical model of the given process, the formation of the cavity during the rolling in the numerical range is replaced by pre-drilling a billet of a specific size given by the mathematical model. The numerical simulations have shown an absolutely fundamental effect of the distribution of the initial temperature field of the billet on the actual piercing process. The billet with the initial inhomogeneous temperature field was subject to very strong transverse oscillations and significant spiral structures appeared in the distribution of all physical quantities. When simulating the piercing process on the Mannesmann piercer in the Tube Mill of Třinecké Železárny, parameterised by a mathematical model so as to take into account in the best possible approximation the influence of the cavity initiation sequence during the actual piercing, the simulation results were completely consistent with the predictions of the mathematical model of the submitted process calibration.

DETERMINATION OF CONDITIONS FOR MAXIMUM DEZINCIFICATION OF A MIXTURE OF FERROUS MATERIALS IN THE SINTERING PROCESS BASED ON NUMERICAL CALCULATIONS USING THE FactSage THERMOCHEMICAL PROGRAM

Abstract: Multi-million tons of sludge produced as a result of wet dedusting of blast furnace and converter gases have been deposited in landfills across the country. These materials are also created on an ongoing basis. Due to the high iron content, their potential as a ferrous raw material is significant. Unfortunately, in addition to components which are desirable from the point of view of metallurgical processes such as Fe, C and CO, they also contain many harmful elements such as Zn, Pb, Na and K. The article describes the sources and form of Zn found in post-production waste of steelworks and the methods of removing zinc from ferrous waste materials. The optimal conditions for zinc removal during the sintering process of galvanised ferrous materials were identified using thermochemical calculations carried out with the FactSage computer program.

The analysis of the rolls cooling at push bench in rolling mill plant žp a.s.

Abstract: This article deals with a comprehensive analysis at roll cooling of push bench on a rolling mill during the rolling process of semi-finished products used for the production of seamless tubes. An important issue that we deal with in this issue is the influence of the cooling parameters using special programmable nozzles of various types with the required flow and water pressure on the final surface temperature of the extruder rollers, at finish quality of shell. The experiment will address the problem of determining the cooling efficiency of different types of nozzles on an experimental device for testing the heat transfer coefficient during cylinder cooling. During experiments maintains development of deformation processes in stands of push bench.

Analysis and comparison of geometric dimensions of cold drawn tubes using fem simulation

Abstract: The paper focuses on the analysis and comparison of tube wall thickness after cold drawing. The tube wall thickness obtained by the experiment was compared with the wall thickness obtained using finite element method (FEM) simulation in the simulation software DEFORM-3D. For the experiment the tube sinking technology was performed and all tubes were made of steel E235. Tubes were the outer diameter of Ø14, Ø16, Ø18 mm and the tube wall thickness was 1 and 2 mm. All tubes were drawn by single-pass tube sinking technology to the final diameter of Ø12 mm. Tube sinking process is a tube drawing technology through a drawing die without the use of a mandrel. Tube sinking is used as a final drawing operation, especially in the production of precision tubes of smaller diameter. The resulting comparison showed that the tube wall thickness obtained by the simulation in the DEFORM software very well matches with tube wall thickness obtained in the experiments. Based on the results, it can be stated that in the future it will be possible to replace some of the real experiments with FEM simulation in the DEFORM software.

Incoloy 800ht iron-based superalloy – preliminary characterisation

Abstract: The article presents and characterises Incoloy 800HT iron-based superalloy in terms of: chemical composition, heat treatment, microstructure and properties, in its delivery condition. This material is commonly used in process lines in the petrochemical industry, e.g. into components called ‘pigtails’.

MICROSTRUCTURE OF CAST MgBi6X0.5 (X = Ca, Mn, Zn) ALLOYS IN PEAK-AGED CONDITION

Abstract: Cast magnesium alloys are characterised by the lowest density among commercially used structural metals. They are applied mainly in the transportation industry and small, lightweight electronic devices. Due to the low operating temperature of the most widely used alloys from the Mg-Al system, alloys containing rare earth elements with the maximum working temperature reaching 300°C have been developed. However, these alloys are extremely expensive due to the low availability of RE elements. The Mg-Bi system is a promising candidate for the new magnesium-based alloys, as it reveals limited solubility of Bi in Mg enabling precipitation hardening and a high melting point of the Mg3Bi2 phase. The paper presents the results of the analysis of MgBi6 and MgBi6X0.5 (X = Ca, Mn, Zn) alloys’ microstructure in the peak-aged condition. The microstructure of the analysed alloys in the as-cast condition consists of α-Mg solid solution dendrites and Mg3Bi2+α-Mg eutectic compound. Solutionising conducted at 525°C for 8 h, followed by water quenching leads to the dissolution of the intermetallic phases in all of the investigated alloys apart of the MgBi6Ca0.5 alloy. In this case, fine intermetallic phases containing Mg, Bi, and Ca have been found after solutionising. The ageing of the alloys at 200°C results in peak hardness after 120–144 h. The heat treatment leads to the formation of fine strengthening phases within the α-Mg solid solution, characterised by a variety of morphologies – needle, platelet- or lathlike and cuboid. The needle- and platelet- or lathlike phases are found in two sizes – large, with length reaching hundreds of nanometres, and smaller, not exceeding 100 nm. Cuboid particles are found with sizes not higher than 100 nm. The addition of Mn and Zn increases precipitate volume fraction after the heat treatment. Additionally, in the case of the MgBi6Zn0.5 alloy, particles forming an angle of 120° were found, which indicates their presence at the prismatic planes of α-Mg HCP crystal lattice.

Decarbonisation pathways of the steel industry

Abstract: The article was prepared on the basis of reports from the Green Steel for Europe (GREENSTEEL) project funded by the European Union as part of the implementation of the climate and energy goals for 2030 and the long-term strategy for a climate neutral Europe by 2050. A consortium of implementers composed of ten partners from EU countries, including Łukasiewicz – Institute for Ferrous Metallurgy in Gliwice, has identified promising technologies for the decarbonisation of the steel industry, defined technological pathways constituting process chains composed of these technologies, as well as scenarios of the decarbonisation process until 2030 and until 2050. The end result of the project is a set of insights and recommendations for effective clean steel manufacturing solutions suitable for the EU to achieve the EU’s climate and energy goals.

Łukasiewicz research network – institute for ferrous metallurgy – current and future research activities

Abstract: At the beginning of 2023, Łukasiewicz Research Network – Institute for Ferrous Metallurgy (Łukasiewicz – IMŻ) begins its activity in the structure of a new institute under the name of Łukasiewicz Research Network – Upper Silesian Institute of Technology, after consolidation with Łukasiewicz – Institute of Welding and Łukasiewicz – Institute of Electrical Drives and Machines KOMEL. On the eve of this change, this study presents the research achievements of Łukasiewicz – IMŻ in 2022 and the topics planned to be undertaken in 2023. It takes into account projects financed from the national and EU budget for science, as well as the significant involvement of the Institute in the implementation of applied projects that contribute to increasing the innovativeness of the domestic industry, including the energy and defence sectors. Attention was paid to the dynamically developing new hydrogen technologies in metallurgy, additive technologies and high-temperature material characteristics, important for the aerospace industry. At the same time, we would like to announce that the current issue of “Journal of Metallic Materials” is the last issue of our quarterly, publishing original research results in the field of metallurgy, materials engineering, chemistry, environmental protection and management in the iron and steel industry. Its traditions date back to 1949, when the first issue of the journal was published under the title “Prace Badawcze Głównego Instytutu Metalurgii i Odlewnictwa (Research Works of the Central Institute of Metallurgy and Casting)”. In 1976-2018, the quarterly was published under the title “Prace Instytutu Metalurgii Żelaza (Works of the Institute for Ferrous Metallurgy)”. The title changed to the current one in 2019. On behalf of the entire editorial team, we would like to thank all readers and authors of articles and reviewers for their cooperation. The establishment of the new Institute will certainly create conditions for the continuation of publishing activities in a broader substantive scope.

Influence of temperature and structure on the formability of steels for the production of seamless tubes

Abstract: The aim of the paper was to determine the temperature dependence of formability of investigated steels by uniaxial tensile fracture tests under thermomechanical conditions corresponding to punching (1340–1395 °C) and pilger rolling (800–1050 °C) in The Tube Mill TŘINECKÉ ŽELEZÁRNY a.s. The deformation behavior of N1 and 42CrMo4 steels was investigated. In both cases, the effect of the structure on formability was taken into account. In the case of high-temperature examination corresponding to the punching process, the tests were performed on samples taken from the area of the column crystals (i.e. closer to the outer surface of the continuously cast semi-finished product) and also from the area below the column crystals closer to the center. In the case of low-temperature tests corresponding to pilger rolling, the strength-plastic properties were evaluated from an area closer to the inner or closer to the outer surface of the roll after punching. Uniaxial tensile tests to the fracture were performed on the HDS-20 simulator.

Preparation of composite steel with using of hot rolling

Abstract: The paper deals with the unconventional issue of composite steel preparation by hot rolling. Various production possibilities of multilayer composite from austenitic stainless steel AISI 304 and tool high carbon steel AISI D2 were investigated. Samples with 5, 15 and 45 layers were prepared. Optical microstructural analysis were subsequently performed on these samples with the focus on the details of joint and evaluation of the thicknesses of individual layers. In addition, hardness measurements were performed on the prepared samples, including its comparison with the individual steels used. It was confirmed that the hardness increased with increasing number of layers, however in this case, the difference between 15 and 45 layers was only 8 HBW. In addition it was found that the hardness of the prepared 45-layer packet without quenching was higher than that of the base (used) steels.

Unconventional methods of manufacturing thin wires for application as input material in additive manufacturing. part 1: preparation of input material for wire drawing

Abstract: Part 1 of the article presents the technological path of producing semi-finished products for wires constituting input material in additive technologies. On the basis of the developed chemical compositions of experimental Fe-based alloys, laboratory ingots with a square section of 120×120 mm / 130×130 mm were produced, which were then hot rolled into flat bars. In order to select the physical parameters of the drawing tests, numerical modelling of the process was performed. As a result of the simulations, it was found that the calculated drawing force exceeds the capabilities of the experimental drawing machine and for this reason, hydrostatic extrusion was used to produce bars intended for drawing wires. The hydrostatic extrusion method was used to make bars with a diameter of 5 mm from three tested materials, while three experimental steels showed insufficient susceptibility to extrusion at high pressure and cracked at various strain values. An analysis of possible causes of bar breakage during extrusion was carried out on the basis of the results of microstructure examination.

The research of influence size strain and number of draws on dimensional accuracy of seamless tubes made of steel e235 and e355

Abstract: The die drawing process is used as a final drawing operation, especially in the production of precise tubes of smaller diameter, while the advantage of the mentioned technology is a reduction of the drawing force and thereby also the decrease of the risk of possible tube rupture during the drawing process. The paper is focused on the research of the influence of the strain size and the method drawing process on the final thickness of the wall and the outer diameter of the tube during die drawing. The sinking drawing experiment was performed by single-pass and two-pass drawing technology to the final tube diameter Ø12 mm without inter-operational annealing. The output of the paper are bar graphs that allows to compare the influence of the strain size and the method of tube drawing technology (single-pass and two-pass) on the dimensional accuracy of the final Ø12 mm tubes made of E235 and E355 steel. The advantage of the single-pass drawing technology when achieving the required wall thickness within the prescribed tolerance (±10 %) would be a reduction of the number of draws.It was found that only in one case of the two-pass drawing technology of E355 steel tube production, the permitted positive tolerance of the tube wall thickness was slightly exceeded, in the case of increasing the reduction (size strain R) from 24 % to 32 %.

Digital image correlation – method development, scope, principle of functioning, and future goals

Abstract: This paper presents the basics of the Digital Image Correlation System, its algorithm of operation, methods of data recording and implementation. In addition, the paper characterises in detail the standard bench instrumentation necessary for the implementation of this type of measurement. The paper also describes the procedure of sample preparation and classifies the main methods of applying a marker to the surface of the sample. The article highlights the main advantages of the system and the main difficulties associated with its operation, and indicates the important parameters affecting the quality of the measurement. The paper shows a wide range of applications of Digital Image Correlation (DIC) and the possibilities of cooperation with other measurement systems as well as extended versions of the system, such as Digital Volumetric Correlation. The article also outlines further directions for the development of the DIC research methodology including, among others, extending the temperature range in which the method can be applied, as well as increasing the speed of camera image recording. Such modifications will allow the image correlation method to be used for research where it has not yet been possible.

UNCONVENTIONAL METHODS OF MANUFACTURING THIN WIRES FOR APPLICATION AS INPUT MATERIAL IN ADDITIVE MANUFACTURING. PART 2: DRAWING OF Fe-BASED ALLOY WIRES

Abstract: The article presents the technology of drawing thin wires made from selected iron-based alloys for use in additive manufacturing using WAAM method. The final technology of wire production was developed with the use of a drawing bench, depending on the deformed material. Steel wires with a diameter of 1 mm and mechanical properties adapted to the 3D printer were produced.

Microstructure, mechanical properties and geometry of a model batch of semi-spherical steel liners intended for use in the extractive industry

Abstract: The article presents the results of investigation of the microstructure and mechanical properties of Fe-based materials intended for the production of semi-spherical liners for experimental shaped charges. The tests were carried out on samples taken in three directions in relation to the rolling direction: 0°, 45° and 90°, of the following materials: cold-rolled sheets made of DC04 steel, hot-rolled sheets made of 04J steel, and cold-rolled strips made of 004G steel developed at Łukasiewicz – IMŻ and annealed at 650°C. Semi-spherical drawpieces with a diameter of 106.4 mm, intended for liners, were made of the sheets with the use of cold stamping. Tests of the microstructure and HV hardness of samples taken from the test batch were carried out on cross-sections along the pressing direction and the model batch – on sections transverse to the stamping direction The geometry of the model batch drawpieces was also measured. The ferrite grain size evaluation was performed according to the ASTM E112 standard using μgrain software with a grain size evaluation module using counting the number of intersections of grain boundaries with a circle.

Influence of heat treatment on thermo-mechanical fatigue and high temperature creep properties for 316l steel

Abstract: The main purpose of the work was to develop the characteristics of high-temperature structure degradation processes under the synergistic effects of thermo-mechanical fatigue and high temperature creep for samples made of 316L steel in the delivery condition and after heat treatment. The use of heat treatment consisting of solution treatment at 1100°C for 45 minutes and water cooling improved the mechanical properties of 316L steel. Moreover, in fatigue tests, in every case, increasing the strain value in a single cycle leads to a faster sample rupture. An additional aim of the research was also to develop and verify a new innovative research methodology concerning the combination of fatigue cycles with the creep process at elevated temperature, the aim of which is to better reflect the behaviour of the material in real working conditions.

Formability of invar 36 alloy at high temperatures

Abstract: By using of hot tensile tests, which were performed on simulator HDS-20, the formability of Invar 36 alloy was investigated. By a special type of a tensile test, involving a continuous control heating of the tested specimens and their simultaneous load by a constant tensile force of 80 N, a nil-strength temperature of investigated alloy 1419 °C was determined. By continuous uniaxial tensile tests to rupture the strength and plastic properties of the Invar 36 alloy were determined in the wide range of deformation temperatures (from 800 °C to 1390 °C) and mean strain rates (from 0.09 s-1 to 75 s-1). On the basis of obtained results the 3D maps were constructed, expressing the dependence of the contractual hot ultimate tensile strength, hot ductility and hot reduction of area of the Invar 36 alloy on the deformation temperature and on the mean strain rate. Based on the determined plastic properties, the nil-ductility temperature of the investigated alloy of 1390 °C was also determined.

Mechanical properties of p91 and pb2 steel after long-term ageing at 620°c

Abstract: The article presents the results of research on mechanical properties of martensitic steels, X10CrMoVNb9-1 (P91) and X13CrMo- CoVNbNB9-2-1 (PB2), as-received and after 50,000 hours of ageing at 620˚C. The scope of the tests of mechanical properties included a Vickers hardness test, Charpy impact test, and static tensile test. As received, the investigated steels were characterised by relatively high mechanical properties. The long-term effect of temperature and time contributed to a relatively slight decrease in the strength properties and hardness of the tested steels. However, a considerable decrease in the ductility of these alloys was observed. The decrease in mechanical properties after long-term ageing was smaller in the case of the PB2 steel, which was attributed to the beneficial effect of microalloying boron.

Forming of a bimetallic element for the resistance element soldering method

Abstract: The joining of sheet metal parts produced in the material combination of Fe-Fe, Fe-Al as well as Fe-thermoplastic and Al-thermoplastic can be realized by the Resistance Element Soldering (RES). Extruded bimetallic elements were used to form the overlap joint. The semi-finished product for extrusions was a Cu 99.9 tube with dimensions φ6 × 0.5 mm and length 9 mm, filled with Sn60Pb40 solder. “T” shaped overprints were produced in two ways. Simulation in the ANSYS software environment was chosen to optimize, select the appropriate forming process, and design the geometry of the functional parts of the forming tool, allowing to use only one extrusion forming operation. The results of the simulations are the magnitudes of stresses and strains, and different head shape geometries of the bimetallic element extrusions of the three proposed forming methods. The task was to achieve extrusions without defects of the Cu tube shell, such as corrugations and wrinkles. The geometry was observed and compared by macroanalysis of extrusion sections made on a laboratory forming tool.

INFLUENCE OF 2% TITANIUM ADDITION ON MICROSCTRUCTURE AND SELECTED HIGH-TEMPERATURE PROPERTIES OF A NOVEL Co-BASED SUPERALLOY STRENGHTENED WITH L12 PHASE

Abstract: This paper contains selected results of primary microsctructure analysis of a novel superalloy, Co-20Ni-10Al-5Mo-2Nb-2Ti. Research on this class of superalloys was started by J. Sato in 2006, and further expanded by S.K. Makineni in 2015. It is implied that Co-based, W-free superalloys will resolve the issues that the aircraft industry currently faces with Ni-based γ/γ’ superalloys. It is believed that the addition of the Ti alloying element will help with γ’ stabilisation due to high Co3(Mo, Al, Nb) fragmentation. Ti content has to be carefully selected to avoid precipitation of harmful phases, such as Co(Ti, Al).