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Number of results: 14
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Abstract

This article discusses issues related to continuous casting of brass. The tested material was CuZn39Pb2 brass with the use of continuous casting and different parameters of the process. The position consists of a melting furnace with a graphite refining pot of about 4000 cm3 chuting capacity, a graphite crystallizer of 9,5 mm nominal diameter, a primary and secondary cooling system and an extracting system as well. The analysis was carried out in terms of technological parameters of the process and type of charge. Highlighted: feedrate ingot, number of stops, and technological temperatures. The surface quality of the obtained ingots and the structure were analyzed. The most favorable conditions were indicated and technological recommendations indicated. They have been distinguished for ingots for plasticity and other technologies. Favorable casting conditions are low feed and low temperature. Due to the presence of impurities coming from the charge it is disadvantageous to have Ni greater than 0.053% by mass, and Fe more than 0.075% by mass. It is recommended to maintain a high zinc content in the melt which is associated with non-overheating of the metal during casting and earlier melting.

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Authors and Affiliations

P. Kwaśniewski
K. Najman
W. Wołczyński
A.W. Bydałek
P. Schlafka
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Abstract

In this paper results of microstructural observations for series of CuZn39Pb2 alloys produced from qualified scraps are presented. The individual alloy melts were differentiated in terms of thermal parameters of continuous casting as well as refining methods and modifications. Structural observations performed by SEM and TEM revealed formation of different types of intermetallic phases including “hard particles”. EDS results show that “hard particles” are enrich in silicon, phosphorus, iron, chromium and nickel elements. Additionally, formation of Al-Fe-Si and Al-Cr in alloy melts was observed as well. It was found that quantity and morphology of intermetallic phases strongly depends upon the chemical composition of raw materials, process parameters, modifiers and refining procedure applied during casting. It was observed that refining process results in very effective refinement of intermetallic phases, whereas modifiers, particularly carbon-based, results in formation of large particles in the microstructure.

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Authors and Affiliations

A.W. Bydałek
A. Kula
L. Błaż
K. Najman
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Abstract

A comparative analysis of brasses alloys, namely lead-free CuZn (CB771) and lead containing CuZn (CB770), was conducted in this article. The results of the comparative analysis and experimental investigations aimed to provide comprehensive knowledge about the thermophysical properties and solidification characteristics of these alloys. Thermodynamic simulations using Thermo-Calc software and modifications in the chemical composition of the CB771 alloy were employed to approximate its characteristics to those of the lead containing CuZn alloy. Thermal-derivative analysis of the alloys and a technological trial were carried out to determine their solidification characteristics, fluidity, and reproducibility. The casting trials were conducted under identical conditions, and the results were compared for a comprehensive analysis. Additionally, a solidification process simulation was performed using MagmaSoft software to match the thermophysical properties. The aim of this research was to achieve maximum consistency between the simulation results and experimental investigations.
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Bibliography

[1] Zoghipour, N., Tascioglu, E., Celik, F. & Kaynak, Y. (2022) - The influence of edge radius and lead content on machining performance of brass alloys. Procedia CIRP. 112, 274-279. https://doi.org/10.1016/j.procir.2022.09.084 .
[2] Hansen, A. (2019). Bleifreier rotguss als armaturen-undinstallationswerkstoff in der trinkwasserinstallation. METALL Forschung. 73(11), 452-455.
[3] Stavroulakis, P., Toulfatzis, A., Pantazopoulos, G. & Paipetis, A. (2022). Machinable leaded and eco-friendly brass alloys for high performance manufacturing processes: a critical review. Metals. 12(2), 246, 1-31. https://doi.org/10.3390/met12020246.
[4] Schultheiss, F., Johansson, D., Bushlya, V., Zhou, J., Nilsson, K. & Ståhl, J-E. (2017). Comparative study on the machinability of lead-free brass. Journal of Cleaner Production. 149, 366-377. https://doi.org/10.1016/ j.jclepro.2017.02.098.
[5] Johansson, J., Alm, P., M’Saoubi, R., Malmberg, P., Ståhl, J-E. & Bushlya, V. (2022). On the function of lead (Pb) in machining brass alloys. Journal of Advanced Manufacturing Technology. 120, 7263-7275. https://doi.org/10.1007/s00170-022-09205-0.
[6] Acceptance of metallic materials used for products in contact with drinking water, 4MS Common Approach Part B “4MS Common Composition List” Retrieved July, 12, 2022 from http://www.umweltbundesamt.de/en/topics/water/drinking-water/distributing-drinking-water/guidelines-evaluation-criteria.
[7] Directive (EU) 2020/2184 of the European Parliament and of the Council of 16 December 2020 on the quality of water intended for human consumption, Dz.U.L 435/1 of 23.12.2020.
[8] Podrzucki, C. (1991). Cast iron. STOP. (in Polish).
[9] Cholewa, M., Suchoń, J., Kondracki, M. & Jura, Z. (2009). Method of thermal derivative gradient analysis (TDGA). Archives of Foundry Engineering. 9(4), 241-245. ISSN (1897-3310).
[10] Bruna, M. & Sladek, A. (2011). Hydrogen analysis and effect of filtration on final quality of castings from aluminium alloy AlSi7Mg0,3. Archives of Foundry Engineering. 11(1), 5-10.
[11] Ignaszak, Z. (2007). Validation problems of virtual prototyping systems used in foundry for technology optimization of ductile iron castings. Advances in Integrated Design and Manufacturing in Mechanical Engineering II, Springer, 57-79. https://doi.org/10.1007/978-1-4020-6761-7_4.
[12] Fajkiel, A., Dudek, P., Walczak, W. & Zawadzki, P. (2007). Improvement of quality of a gravity die casting made from aluminum bronze be application of numerical simulation. Archives of Foundry Engineering. 7(2), 11-14. ISSN (1897-3310).
[13] Persson, P-E., Ignaszak, Z., Fransson, H., Kropotkin, V., Andersson, R. & Kump, A. (2019). increasing precision and yield in casting production by simulation of the solidification process based on realistic material data evaluated from thermal analysis (Using the ATAS MetStar System). Archives of Foundry Engineering. 19(1), 117-126. DOI: 10.24425/afe.2019.127104.
[14] Ignaszak, Z. & Wojciechowski, J. (2020). Analysis and validation of database in computer aided design of jewellery casting. Archives of Foundry Engineering. 20(1), 9-16. DOI: 10.24425/afe.2020.131275.

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Authors and Affiliations

Grzegorz Radzioch
1 2
Dariusz Bartocha
1
ORCID: ORCID
Marcin Kondracki
1
ORCID: ORCID

  1. Department of Foundry Engineering, Silesian University of Technology, 7 Towarowa Str. 44-100 Gliwice, Poland
  2. Joint Doctoral School, Silesian University of Technology, 2A Akademicka Str. 44-100 Gliwice, Poland
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Abstract

Trial series of cast alloy MO59 obtained from qualified scrap was investigated. SEM and TEM of resulting precipitates were conducted.

The SEM analysis demonstrated the dependence of silicon, phosphorus, iron, chromium and nickel in the composition of the so-called

hard precipitates. TEM analysis showed the formation of phase AlFeSi and AlCr. Made studies have shown the important role of the

composition of the batch melts brass CuZn39Pb2 type. The analysis of SEM and TEM resulting precipitates pointed to the formation of

various forms of divisions, only one of which was described in the literature character of the so-called hard inclusions. The SEM studies

demonstrated the dependence of the occurrence of inclusions rich in silicon, phosphorus, iron, chromium and nickel. In contrast, additional

TEM analysis indicated the formation of AlFeSi phase type and AlCr. The results of the analyses referred to the structure of the batch. Due

to the difficulty of obtaining recycled materials that do not contain these elements necessary to carry out further analyzes in the direction

of defining the role of phosphorus in the formation of the so-called hard inclusions.

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Authors and Affiliations

K. Najman
W. Wołczyński
A.W. Bydałek
S. Biernat
L. Błaż
A. Kula
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Abstract

The article presents the results of research on the finishing of M63 Z4 brass by vibratory machining. Brass alloy was used for the research due to the common use of ammunition elements, cartridge case and good cold forming properties on the construction. Until now, the authors have not met with the results of research to determine the impact of abrasive pastes in container processing. It was found that the additive for container abrasive treatment of abrasive paste causes larger mass losses and faster surface smoothing effects. The treatment was carried out in two stages: in the first stage, the workpieces were deburred and then polished. Considerations were given to the impact of mass of workpieces, machining time and its type on mass loss and changes in the geometric structure of the surface. The surface roughness of machining samples was measured with the Talysurf CCI Lite optical profiler. The suggestions for future research may be to carry out tests using abrasive pastes with a larger granulation of abrasive grains, and to carry out tests for longer processing times and to determine the time after which the parameters of SGP change is unnoticeable.

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Authors and Affiliations

D. Bańkowski
ORCID: ORCID
S. Spadło
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Abstract

Source/filter models have frequently been used to model sound production of the vocal apparatus and musical instruments. Beginning in 1968, in an effort to measure the transfer function (i.e., transmission response or filter characteristic) of a trombone while being played by expert musicians, sound pressure signals from the mouthpiece and the trombone bell output were recorded in an anechoic room and then subjected to harmonic spectrum analysis. Output/input ratios of the signals’ harmonic amplitudes plotted vs. harmonic frequency then became points on the trombone’s transfer function. The first such recordings were made on analog 1/4 inch stereo magnetic tape. In 2000 digital recordings of trombone mouthpiece and anechoic output signals were made that provide a more accurate measurement of the trombone filter characteristic. Results show that the filter is a high-pass type with a cutoff frequency around 1000 Hz. Whereas the characteristic below cutoff is quite stable, above cutoff it is extremely variable, depending on level. In addition, measurements made using a swept-sine-wave system in 1972 verified the high-pass behavior, but they also showed a series of resonances whose minima correspond to the harmonic frequencies which occur under performance conditions. For frequencies below cutoff the two types of measurements corresponded well, but above cutoff there was a considerable difference. The general effect is that output harmonics above cutoff are greater than would be expected from linear filter theory, and this effect becomes stronger as input pressure increases. In the 1990s and early 2000s this nonlinear effect was verified by theory and measurements which showed that nonlinear propagation takes place in the trombone, causing a wave steepening effect at high amplitudes, thus increasing the relative strengths of the upper harmonics.

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Authors and Affiliations

James W. Beauchamp
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Abstract

This article contains information concerning of the analysis the possibility of defining refinery qualities of the slag based thermophysical and thermodynamical data. The paper presents a model of slag refining processes and a method of determining the reduction capability of slag solutions. Slag was analysed with the use of the DTA methods for the brass melting conductions. The study of computer program including the satisfactory number of data there are used in to the design a modern device rotating head used for gas-slag refining. It was achieved that the refining gas and fluxes were distributed ever by the rotating head. High effectiveness of the gas-slag refining processes was proved for the brass.

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Authors and Affiliations

A. Bydałek
S. Biernat
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Abstract

The article describes the optimization of the melting brass. Brasses, as one of the most popular alloys of copper, deserve special attention

in the context of the processes of melting, which in turn would provide not only products of better quality, but also reduce the cost of their

production or refining. For this purpose, several studies carried out deriatographic (DTA) and thermogravimetric (TG) using

derivatograph. The results were confronted with the program SLAG - PROP used to evaluate the physicochemical properties of the

coatings extraction. Based on the survey and analysis of the program can identify the most favorable physico - chemical properties, which

should be carried out treatments. This allows for slag mixtures referred configurations oxide matrix containing specific stimulators of the

reaction. Conducted empirical studies indicate a convergence of the areas proposed by the application. It should also be noted that the

program also indicates additional areas in which to carry out these processes would get even better, to optimize the melting process, the

results.

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Authors and Affiliations

A.W. Bydałek
S. Biernat
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Abstract

The article presents an integrated analytical and measurement system for evaluation of the properties of cast metals and alloys. The presented platform is an extension of the SLAG - PROP application with new modules, which allow to use information on metallurgical processes in an even more effective way, as well as to evaluate the finished product. In addition, the construction of a measuring station for the analysis of thermal processes taking place in a metal bath allows for precise observation of phenomena together with their appropriate interpretation. The article presents not only the cooling curves of certain copper alloys. The analysis also covered mechanical properties related to hardness, finished products depending on the mold in which the products were cast. In the literature one can find information about the mechanical properties of products in the improved state, usually after plastic or thermal treatment, omitting their properties obtained as a result of a naturally made casting. The article also presents the method of placing information in the database using a convenient graphical tool.

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Authors and Affiliations

S. Biernat
A.W. Bydałek
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Abstract

An innovative method for determining the structural zones in the large static steel ingots has been described. It is based on the

mathematical interpretation of some functions obtained due to simulation of temperature field and thermal gradient field for solidifying

massive ingot. The method is associated with the extrema of an analyzed function and with its points of inflection. Particularly, the CET

transformation is predicted as a time-consuming transition from the columnar- into equiaxed structure. The equations dealing with heat

transfer balance for the continuous casting are presented and used for the simulation of temperature field in the solidifying virtual static

brass ingot. The developed method for the prediction of structural zones formation is applied to determine these zones in the solidifying

brass static ingot. Some differences / similarities between structure formation during solidification of the steel static ingot and virtual brass

static ingot are studied. The developed method allows to predict the following structural zones: fine columnar grains zone, (FC), columnar

grains zone, (C), equiaxed grains zone, (E). The FCCT-transformation and CET-transformation are forecast as sharp transitions of the

analyzed structures. Similarities between steel static ingot morphology and that predicted for the virtual brass static ingot are described.

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Authors and Affiliations

A.A. Ivanova
B. Kania
P. Kwapisiński
W. Wołczyński
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Abstract

The article deals with ultrasonic testing possibilities of the copper alloy centrifugal casts. It focused on the problems that arise when testing

of castings is made of non-ferrous materials. Most common types of casting defects is dedicated in theoretical introduction of article.

Ultrasonic testing technique by conventional ultrasound system is described in the theoretical part too. Practical ultrasonic testing of

centrifugal copper alloy cast - brass is in experimental part. The experimental sample was part of centrifugally cast brass ring with

dimensions of Ø1200x34 mm. The influence of microstructure on ultrasonic attenuation and limitations in testing due to attenuation is

describes in experimental part. Conventional direct single element contact ultrasound probe with frequencies of 5 MHz, 3.5 MHz and 2

MHz were used for all experimental measurements. The results of experimental part of article are recommendations for selecting

equipment and accessories for casting testing made of non-ferrous metals.

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Authors and Affiliations

R. Konar
M. Mician
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Abstract

Some metallographic studies performed on the basis of the massive forging steel static ingot, on its cross-section, allowed to reveal the

following morphological zones: a/ columnar grains (treated as the austenite single crystals), b/ columnar into equiaxed grains

transformation, c/ equiaxed grains at the ingot axis. These zones are reproduced theoretically by the numerical simulation. The simulation

was based on the calculation of both temperature field in the solidifying large steel ingot and thermal gradient field obtained for the same

boundary conditions. The detailed analysis of the velocity of the liquidus isotherm movement shows that the zone of columnar grains

begins to disappear at the first point of inflection and the equiaxed grains are formed exclusively at the second point of inflection of the

analyzed curve. In the case of the continuously cast brass ingots three different morphologies are revealed: a/ columnar structure, b/

columnar and equiaxed structure with the CET, and c/ columnar structure with the single crystal formation at the ingot axis. Some

forecasts of the temperature field are proposed for these three revealed morphologies. An analysis / forecast of the behavior of the

operating point in the mold is delivered for the continuously cast ingot. A characteristic delay between some points of breakage of the

temperature profile recorded at the operating point and analogous phenomena in the solidifying alloy is postulated.

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Authors and Affiliations

W. Wołczyński
A.W. Bydałek
Z. Lipnicki
A.A. Ivanova
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Abstract

Experimental observations of the steel morphology as well as measurements of the solutes concentration in the macro-scale were made on the basis of the vertical cut at the mid-depth of the 15-tons steel forging ingot serially produced in one of the steel plant in Poland. Experimental observations of the morphology accompanied by the measurements of the Peclet Number were also made on the cross-section of the continuously cast brass ingots serially produced in the copper / brass industry in Poland. The performed measurements allowed to work out some maps of the alloying elements segregation for the longitudinal section of the steel static ingot and a Growth Law for the columnar grains formation in the brass ingots. The marginal stability criterion has been applied to the last mentioned development / description. Some suggestions for the micro-segregation measurement mode in the columnar structure are derived.

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Authors and Affiliations

W. Wołczyński
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Abstract

The Structural Peclet Number has been estimated experimentally by analyzing the morphology of the continuously cast brass ingots. It

allowed to adapt a proper development of the Ivantsov’s series in order to formulate the Growth Law for the columnar structure formation

in the brass ingots solidified in stationary condition. Simultaneously, the Thermal Peclet Number together with the Biot, Stefan, and

Fourier Numbers is used in the model describing the heat transfer connected with the so-called contact layer (air gap between an ingot and

crystallizer). It lead to define the shape and position of the s/l interface in the brass ingot subjected to the vertical continuous displacement

within the crystallizer (in gravity). Particularly, a comparison of the shape of the simulated s/l interface at the axis of the continuously cast

brass ingot with the real shape revealed at the ingot axis is delivered. Structural zones in the continuously cast brass ingot are revealed: FC

– fine columnar grains, C – columnar grains, E – equiaxed grains, SC – single crystal situated axially.

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Authors and Affiliations

A.A. Ivanova
Z. Lipnicki
P. Kwapisiński
W. Wołczyński

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