Applied sciences

Archives of Foundry Engineering

Content

Archives of Foundry Engineering | 2015 | No 3 |

Abstract

It is demonstrated that during secondary refining at the ladle furnace the carbon content of steel and the residence time of the metal in the

ladle exert a significant impact on the residual content of non-metallic inclusions (NMI) in steel. Mathematical calculations showed that

the dynamic forces have minor effect on the motion of small sized NMI, making it difficult to penetrate deep into the slag.

Go to article

Abstract

The production process of prosthetic restorations runs in two stages. In the first stage, the prosthetic foundation is produced of metal

alloys. In the second stage, a facing material is applied on the produced element. In both stages, the wettability is significantly important,

as well as the free surface energy relating to it. The quality of the obtained cast depends on the surface phenomena occurring between the

metal alloy and the material of which the casting mould is made. The performed examinations also point to a relation between the ceramics

joint and the base, depending on the wetting angle.

The aim of the presented paper was to examine influence of the composition of a Ti(C,N)-type coating on bases made of the Ni-Cr

prosthetic alloy on the wettability and the surface free energy.

The test material were disks made of the Ni-Cr alloy with the diameter of 8 mm. The disks were divided into five groups, which were

covered with Ti(C,N) coatings, with different amounts of C and N in the layer. In order to determine the surface free energy (����), the

wetting angle was measured. Two measure liquids were applied: distilled water and diiodomethane.

The obtained results of the measurements of the water-wetting angles suggest that together with the increase of the ratio of nitrogen to

carbon in the Ti(C,N) coating, the surface hydrophobicity increases as well. In all the samples, one can see a large difference between the

energy values of the polar and the apolar components. The high values of the polar components and the low values of the apolar ones make

it possible to conclude that these surfaces exhibit a greater affinity to the polar groups than to the apolar ones.

On the basis of the analysis of the surface free energy, one can state that covering the alloy with Ti(C,N)-type coatings should not decrease

the adhesion of the ceramics to the alloy, whereas TiC coatings should lead to the latter’s improvement. Due to their hydrophilicity, TiC

coatings should decrease the adhesion of bacteria to the surface and hinder the formation of a bacterial biofilm.

Go to article

Abstract

In current casting technology of cored, thin walled castings, the modifying coating is applied on the surface of wax pattern and, after the

removal of the wax, is transferred to inner mould surface. This way the modification leading to grain refinement occur on the surface of

the casting. In thin walled castings the modification effect can also be seen on the other (external) side of the casting. Proper reproduction

of details in thin walled castings require high pouring temperature which intensify the chemical reactions on the mould – molten metal

interface. This may lead to degradation of the surface of the castings. The core modification process is thought to circumvent this problem.

The modifying coating is applied to the surface of the core. The degradation of internal surface of the casting is less relevant. The most

important factor in this technology is “trough” modification – obtaining fine grained structure on the surface opposite to the surface

reproduced by the core.

Go to article

Abstract

Discusses an attempt to optimize the operation of an electric furnace slag to be decopperisation suspension of the internal recycling

process for the production of copper. The paper presents a new method to recover copper from metallurgical slags in arc-resistance electric

furnace. It involves the use of alternating current for a first period reduction, constant or pulsed DC in the final stage of processing. Even

distribution of the electric field density in the final phase of melting caused to achieve an extremely low content of metallic copper in the

slag phase. They achieved by including the economic effects by reducing the time reduction.

Go to article

Abstract

The paper, especially dealt with problems of reclamation of used furan sand, carried out in new, vibratory sand reclamation unit REGMAS

developed by researches from AGH-University of Science and Technology, Faculty of Foundry Engineering in Cracow (Poland).

Functional characteristics of reclamation unit as well as the results of reclamation of used sand with furfuryl resin are discussed in the

paper. The quality of reclaim was tested by means of the LOI and pH value, dust content in the reclaim and at least by the the quality of

the castings produced in moulds prepared with the use of reclaimed matrix.

Go to article

Abstract

The paper presents the results of studies of the effect of chromium concentration on the solidification process, microstructure and selected

properties of cast iron with vermicular graphite. The vermicular graphite cast iron was obtained by an Inmold process. Studies covered the

cast iron containing chromium in a concentration at which graphite is still able to preserve its vermicular form. The effect of chromium on

the temperature of eutectic crystallization and on the temperature of the start and end of austenite transformation was discussed. The conditions

under which, at a predetermined chromium concentration, the vermicular graphite cast iron of a pearlitic matrix is obtained were

presented, and the limit concentration of chromium was calculated starting from which partial solidification of the cast iron in a metastable

system takes place. The effect of chromium on the hardness of cast iron, microhardness of individual phases and surface fraction of carbides

was disclosed.

Go to article

Abstract

The paper presents results of Ti-addition to High Chromium Cast Iron (HCCI) on the structure and selected mechanical properties. For this

study casted two sets of cylinders with dimensions ø20 mm, ø15 mm x 250 mm, for the High Chromium Cast Iron (HCCI) and with the

4% by mass Ti-addition. Melts were performed in the induction furnace crucible capacity of 15 kg. During the heats the cup with installed

S type thermocouple was poured to record the cooling curves. The cylinders were subjected to the static bending strength test. Samples for

the test microstructure and Rockwell hardness were cut from the cylinders. The study shows that the addition of titanium had an impact on

the structure and thus the properties of High Chromium Cast Iron (HCCI). In subsequent studies, through an appropriate choice of

chemical composition and proper process control, it is planned to obtain in the structure the titanium carbides TiC and chromium carbides

with type (Cr, Fe)7C3.

Go to article

Abstract

The presented work describes the results of examination of the mechanical properties of castings made either of AlSi9Mg alloy matrix

composite reinforced with short carbon fibre or of the pure AlSi9Mg alloy. The tensile strength, the yield strength, Young’s modulus, and

the unit elongation were examined both for initial castings and for castings made of the remelted composite or AlSi9Mg alloy. After

preparing metallographic specimens, the structure of the remelted materials was assessed. A few non-metallic inclusions were observed in

the structure of the remelted composite, not occurring in the initial castings. Mechanical testing revealed that all the examined properties of

the initial composite material exceed those of the non-reinforced matrix. A decrease in mechanical properties was stated both for the metal

matrix and for the composite after the remelting process, but this decrease was so slight that it either does not preclude them from further

use or does not restrict the range of their application.

Go to article

Abstract

The paper presents the results of basic research on the influence of the properties of sand grains on electrical properties of water glass

moulding sands. It shows electrical properties of the main component – sand grains, crucial to the kinetics of moulding sands heating, such

as permittivity εr and loss factor tgδ. Measurements were carried out with the use of the perturbation method for silica, chromite and

olivine sands of different mineral, chemical composition and particle size distribution, as well as for moulding sands with water glass

grade 145. Analysis of the results of measurements of electrical properties shows that all moulding sands are characterized by a similar

permittivity εr and loss factor tgδ. It was found that the electrical properties and the quantity and quality of other components may have

a decisive influence on the effectiveness and efficiency of the microwave heating of moulding sands with sand grains. In determining the

ability to efficiently absorb the microwave radiation for mixtures which moulding sands are, the impact of all components influencing their

individual technological parameters should be taken into account.

Go to article

Abstract

In the dissertation the data modeling has been shown for the data that regards the damages, which value is above zero. With the use of

Weibull distribution, with prior regression and correlation analysis chosen parameters that defines the life time and failure level of two

populations of AlSi17Cu5 were defined. The calculation sheet of reliability allows to create so called survival diagram, and on the basis of

durability data the average warrantee can be determined, on the pre-exploitation period.

Go to article

Abstract

The work presents the results of the investigations of the effect of inhibitors coated on the internal walls of a ceramic mould on the quality

of the obtained casts made of the AM60 alloy containing additions of chromium and vanadium. In order to reduce the reactivity of

magnesium alloy cast by the technology of investment casting with the material of the mould and the ambient atmosphere, solid inhibitors

were applied in the form of a mixture of KBF4 and H3BO3 after the stage of mould baking and before the mould’s being filled with the

liquid alloy. For the purpose of examining the effect of the inhibitors on the surface quality of the obtained casts, profilometric tests were

performed and the basic parameters describing the surface roughness, Ra, Rz and Rm, were determined.

Go to article

Abstract

The paper presents the results of investigation into the technological possibility of making light-section castings of GX2CrNiMoN25-6-3

cast steel. For making castings with a wall thickness in the thinnest place as small as below 1 mm, the centrifugal casting technology was

employed. The technology under consideration enables items with high surface quality to be obtained, while providing a reduced

consumption of the charge materials and, as a result, a reduction in the costs of unit casting production.

Go to article

Abstract

The work presents the results of the examinations of silumin 226 as well as a silumin produced on its basis containing a W and Mo addition

introduced in the amount of 0.1; 0.2; 0.3 and 0.4% of both elements simultaneously. Investigations of the crystallization process of the

silumins by the TDA method were conducted. Also, a microscopic analysis of their microstructure was performed and their basic mechanical

properties were determined. Microstructure tests were made on casts produced in an TDA sampler as well as by the pressure method.

The investigations exhibited a change in the course of crystallization of the silumin containing 0.3 and 0.4% W and Mo with respect to

silumin 226 and the silumin with the addition of 0.1 and 0.2%. The presence of additional phases which did not occur in the case of lower

addition contents was established in the silumin containing 0.3-0.4% W and Mo, regardless of the applied casting technology. The tests

showed the possibility of increasing the tensile strength Rm, the proof stress Rp0,2 and the unit elongation A of the silumin as a result of a

simultaneous introduction of the W and Mo addition. The highest values of Rm, Rp0,2 and A were obtained in the silumins with the additions

of these elements within the range of 0.1-0.2% each.

Go to article

Abstract

As experience shows the practical, reliable assessment and optimisation of total costs of logistical processes implemented in supply chains

of foundry plants is a quite complex and complicated process, because it requires to enclose all, without exception, performed actions,

including them in various reference cross-sections, systematic activities and finally transforming them in a totally homogenous collection.

Only solid analysis and assessment of assortment management in logistical supply systems in foundry plants of particular assortment

groups allows to lower the supply costs significantly. In the article the analysis and assessment of the newest implemented optimising

algorithms are presented in the process stock management of selected material groups used in a production process of a chosen foundry

plant. A practical solution to solve a problem of rotary stock cost minimisation is given as well as of costs while creating a stock with the

usage of economical volume and value of order.

Go to article

Abstract

Directionally solidified sample of Fe-Fe3C eutectic alloy were produced under an argon atmosphere in a vacuum Bridgman-type furnace to

study the eutectic growth with v = 167 μm/s pulling rate and constant temperature gradient G = 33.5 K/mm. Since how the growth texture

of eutectic cementite is related to its growth morphology remains unclear, the current study aims to examine this relationship. The technique

such as X-ray diffraction, have been used for the crystallographic analysis of carbide particles in white cast irons.

Go to article

Abstract

The main scope of the article is the development of a computer system, which should give advices at problem of cooper alloys

manufacturing. This problem relates with choosing of an appropriate type of bronze (e.g. the BA 1044 bronze) with possible modification

(e.g. calcium carbide modifications: Ca + C or CaC2) and possible heat treatment operations (quenching, tempering) in order to obtain

desired mechanical properties of manufactured material described by tensile strength - Rm, yield strength - Rp0.2 and elongation - A5. By

construction of the computer system being the goal of presented here work Case-based Reasoning is proposed to be used. Case-based

Reasoning is the methodology within Artificial Intelligence techniques, which enables solving new problems basing on experiences that

are solutions obtained in the past. Case-based Reasoning also enables incremental learning, because every new experience is retained each

time in order to be available for future processes of problem solving. Proposed by the developed system solution can be used by

a technologist as a rough solution for cooper alloys manufacturing problem, which requires further tests in order to confirm it correctness.

Go to article

Abstract

The paper presents the results of the crystallization process of silumin by the TDA thermographic method and the results of the cast

microstructure obtained in the sampler TDA-10, that was cooling down in ambient air. The study was conducted for silumin AlSi11

unmodified. The work demonstrated that the use of thermal imaging camera allows for the measurement and recording the solidification

process of silumin. Thermal curve was registered with the infrared camera and derivative curve that was calculated on the base of thermal

curve have both a very similar shape to adequate them TDA curves obtained from measurements using a thermocouple. Test results by

TDA thermographic method enable quantitative analysis of the kinetics of the cooling and solidification process of neareutectic silumin.

Go to article

Abstract

In paper is presented results of studies concerning ingot of Al with a purity of 99.5% cast with use of stand of horizontal continuous

casting. Mainly together with casting velocity was considered influence of electromagnetic stirrer, which was placed in continuous casting

mould on refinement of ingots structure and theirs usability to plastic deformation. Effect of structure refinement and usability to plastic

deformation obtained by influence of electromagnetic stirring was compared with refinement obtained by use of traditional inoculation,

which consists in introducing of additives i.e. Ti and B to metal bath. On the basis of obtained results was affirmed that inoculation

realized by electromagnetic stirring in range of continuous casting mould guarantees improvement in structure refinement and usability to

rolling of pure Al continuous ingots.

Go to article

Abstract

This paper presents the findings of a study of gas emissivity and the volumetric gas flow rate from a patented modified cellulose mix used

in production of disposable sand casting moulds. The modified cellulose mix with such additives as expanded perlite, expanded

vermiculite and microspheres was used as the study material. The results for gas emissivity and the gas flow rate for the modified cellulose

mix were compared with the gas emissivity of the commercial material used in gating systems in disposable sand casting moulds. The

results have shown that the modified cellulose mix is characterized by a lower gas emissivity by as much as 50% and lower gas flow rate

per unit mass during the process of thermal degradation at the temperature of 900°C, compared to the commercial mix. It was also noted

that the amount of microspheres considerably affected the amount of gas produced.

Go to article

Abstract

The article discusses the weldment to casting conversion process of rocker arm designed for operation in a special purpose vehicle to

obtain a consistency of objective functions, which assume the reduced weight of component, the reduced maximum effort of material

under the impact of service loads achieved through topology modification for optimum strength distribution in the sensitive areas, and the

development of rocker arm manufacturing technology. As a result of conducted studies, the unit weight of the item was reduced by 25%,

and the stress limit values were reduced to a level guaranteeing safe application.

Go to article

Editorial office

CHIEF EDITORS
Editor
J. Szajnar
Deputy Editor
J. Jezierski

SUBJECT EDITORS
Theoretical Aspects of Casting Processes
K. Eigenfeld – Freiberg, Germany
E. Guzik – Kraków, Poland
T. G. Mathia - Lyon, France
W. Wołczyński – Kraków, Poland
Innovative Foundry Technologies and Materials
T. Elbel – Ostrava, Czech Republic
Z. Ignaszak – Poznań, Poland
O. P. Pandey – Punjab, India
A. Pereira - Vigo, Spain
Foundry Processes Computer Aiding
B. Mochnacki – Częstochowa, Poland
J. Roučka – Brno, Czech Republic
J.S. Suchy – Kraków, Poland
Mechanization, Automation and Robotics in Foundry
J. Bast – Freiberg, Germany
R. Wrona – Kraków, Poland
Transport Systems in Foundry
J. Dańko – Kraków, Poland
Z. Li – Shijiazhuang, China
Castings Quality Management
D. Bolibruchova– Żilina, Slovak Republic
J. D. B. de Mello - Santa Monica, Brazil
M. Perzyk – Warszawa, Poland
Environment Protection
M. Holtzer – Kraków, Poland
H. Polzin – Freiberg, Germany
J. Sobczak – Kraków, Poland
I. Volchok – Zaporizhzhya, Ukraine

EDITORIAL ADVISORY BOARD
J. Braszczyński – Częstochowa, Poland
B. K. Dhindaw – Rupnagar, India
L. A. Dobrzański – Gliwice, Poland
W. A. Hufenbach – Dresden, Germany
P. Jelínek – Ostrava, Czech Republic
L. Jeziorski – Częstochowa, Poland
J. Lacaze – Toulouse, France
V. L. Naydek – Kiev, Ukraine
A. Passerone – Genova, Italy
I. Riposan – Bucharest, Romania
F. Romankiewicz – Zielona Góra, Poland
A. Sládek – Żilina, Slovak Republic

INTERNATIONAL SCIENTIFIC REVIEW COMMITTEE
S. A. Argyropoulos – Toronto, Canada
M. Azadi – Tehran, Iran
Y. Babaskin – Kiev, Ukraine
K. Bako – Miskolc, Hungary
E. Bayraktar – Paris, France
L. Bechný – Zilina, Slovak Republic
V. Bednarova - Ostrava, Czech Republic
F. Bińczyk – Katowice, Poland
A. Bokota – Częstochowa, Poland
G.P. Borisov – Kiev, Ukraine
A. Bydałek – Kraków, Poland
C. H. Cáceres – Brisbane, Australia
J. Čech – Brno, Czech Republic
L. Q. Chen – Shenyang, China
A. Chojecki – Kraków, Poland
M. Cholewa – Gliwice, Poland
I. A. Dibrov – Moscow, Russia
D. Dispinar – Istanbul, Turkey
S. M. Dobosz – Kraków, Poland
V. I. Dubodelov – Kiev, Ukraine
A. Fedoryszyn – Krakow, Poland
J. Głownia – Kraków, Poland
K. Granat – Wrocław, Poland
J. Hampl – Ostrava, Czech Republic
J. Helber – Düsseldorf, Germany
M. Hetmańczyk – Katowice, Poland
M. Horáček – Brno, Czech Republic
M. Kaczorowski – Warszawa, Poland
W. Kapturkiewicz – Kraków, Poland
R. Kawalla – Freiberg, Germany
Z. Konopka – Czestochowa, Poland
D. Kopyciński – Kraków, Poland
W. K. Krajewski – Kraków, Poland
Z. Libo – Beijing, China
P. Lichy – Ostrava, Czech Republic
Y. P. Lim – Setapak, Malaysia
T. Lipiński – Olsztyn, Poland
E. Majchrzak – Gliwice, Poland
A. Mityayev - Zaporizhzhya, Ukraine
M. Murgaš – Trnava, Slovak Republic
I. Nová – Liberec, Czech Republic
W. Orłowicz – Rzeszów, Poland
T. Pacyniak – Łódź, Poland
B. Piekarski – Szczecin, Poland
A. Rimmer – West Bromwich, United Kingdom
S. Samavedam – Hyderabad, India
P. Schumacher – Leoben, Austria
N. Sczygiol – Częstochowa, Poland
P. Skočovský – Żilina, Slovak Republic
M.S. Soiński – Częstochowa, Poland
J. Sokolowski – Ottawa, Kanada
K. V. Sudhakar – Butte, USA
B. G. Thomas - Champaign, USA
M. Trbižan – Ljubljana, Slovenia
J. Vuorinen – Tampere, Finland
E. Ziółkowski – Kraków, Poland
J. Zych – Kraków, Poland

ASSOCIATE EDITORS
D. Bartocha – Gliwice, Poland, - editorial secretary
J. Suchoń – Gliwice, Poland - editorial secretary
J. Szymszal – Katowice, Poland, Statistic Editor
A. Dulska – Gliwice, Poland
M. Kondracki – Gliwice, Poland
C. Borek –Chicago, USA, Language Editor

 

Contact

ul. Towarowa 7,
44-100 Gliwice, Poland
e-mail: kikm@polsl.pl

This page uses 'cookies'. Learn more