Partner: D. Kaliński


Recent publications
1.Nosewicz Sz., Rojek J., Pietrzak K., Chmielewski M., Kaliński D., Modelowanie procesu spiekania materiałów dwufazowych metodą elementów dyskretnych, RUDY I METALE NIEŻELAZNE, ISSN: 0035-9696, Vol.57, No.9, pp.599-603, 2012
Abstract:

W niniejszym artykule zostały przedstawione nowe wyniki modelowania procesu spiekania metodą elementów dyskretnych. W sformułowaniu teoretycznym dla części sprężystej zastosowano model kontaktu Hertza w celu lepszego odwzorowania oddziaływania elementów kulistych w trakcie prasowania. Sformułowanie i implementację modelu rozszerzono na przypadek spiekania materiałów dwufazowych. Na podstawie badań literaturowych wyznaczono parametry materiałowe procesu, które zostały następnie zweryfikowane za pomocą wyników eksperymentalnych. Wyniki numeryczne ewolucji gęstości próbki porównano z wynikami doświadczalnymi otrzymując dużą zgodność.

Keywords:

materiały dwufazowe, metalurgia proszków, spiekanie, metoda elementów dyskretnych

Affiliations:
Nosewicz Sz.-IPPT PAN
Rojek J.-IPPT PAN
Pietrzak K.-IPPT PAN
Chmielewski M.-Institute of Electronic Materials Technology (PL)
Kaliński D.-other affiliation
2.Rojek J., Pietrzak K., Chmielewski M., Kaliński D., Nosewicz S., Discrete Element Simulation of Powder Sintering, COMPUTER METHODS IN MATERIALS SCIENCE / INFORMATYKA W TECHNOLOGII MATERIAŁÓW, ISSN: 1641-8581, Vol.11, No.1, pp.68-73, 2011
Abstract:

This paper presents numerical modelling of powder sintering. The numerical model introduced in this work employs the discrete element method which assumes that material can be modelled by a large assembly of discrete elements (particles) of spherical shape interacting among one another. Modelling of sintering requires introduction of the cohesive interaction among particles representing inter-particle sintering forces. Numerical studies of sintering have been supplemented with experimental studies which provided data for calibration and validation of the model. In the laboratory tests evolution of microstructure and density during sintering have been studied. Comparison of numerical and experimental results shows a good performance of the numerical model developed.

Keywords:

powder sintering, powder metallurgy, simulation, discrete element method

Affiliations:
Rojek J.-IPPT PAN
Pietrzak K.-IPPT PAN
Chmielewski M.-Institute of Electronic Materials Technology (PL)
Kaliński D.-other affiliation
Nosewicz S.-IPPT PAN
3.Węglewski W., Chmielewski M., Kaliński D., Pietrzak K., Basista M., Thermal residual stresses generated during processing of Cr/Al2O3 composites and their influence on macroscopic elastic properties, Advances in Science and Technology, ISSN: 1662-0356, DOI: 10.4028/www.scientific.net/AST.65.27, Vol.65, pp.27-32, 2010
Abstract:

This work is focused on the modeling of thermal stresses induced during the fabrication of the metal/ceramic composites. On example of Cr-Al2O3 composite processed by powder metallurgy, thermal stresses after fabrication are determined by FEM model for different contents of metal and ceramic phases. Numerical model of microcracking induced by thermal stresses is then proposed and applied to compute the overall elastic properties of the damaged composite. Comparison of the model predictions with the measur ed data for Young's modulus is presented.

Keywords:

Cr-Al2O3 composite, mechanical properties, thermal stress modeling, microcracking, Young’s modulus modeling

Affiliations:
Węglewski W.-IPPT PAN
Chmielewski M.-Institute of Electronic Materials Technology (PL)
Kaliński D.-other affiliation
Pietrzak K.-IPPT PAN
Basista M.-IPPT PAN
4.Chmielewski M., Pietrzak K., Kaliński D., Strojny A., Processing and thermal properties of Cu-AlN composites, Advances in Science and Technology, ISSN: 1662-0356, DOI: 10.4028/www.scientific.net/AST.65.100, Vol.65, pp.100-105, 2010
Abstract:

Heat transfer by conduction is involved in the use of heat sinks dissipitating heat from electronic devices. Effective transfer of heat requires using materials of high thermal conductivity. In addition, it requires appropriate values of thermal expansion, matched to the semiconductor materials, high purity of materials used and good contact between bonded elements across which heat transfer occurs. The conventional materials are not able to fulfil still raising and complex requirements. The solutions of this problem could be using the composites materials, where the combinations of different properties is possible to use. This study presents the technological tests and the analysis of correlation between processing parameters and the properties of copperaluminium nitride composites. Composite materials were obtained by mixing in planetary ball mill and then densified using the sintering under pressure or hot pressing method. The microstructure of obtained composite materials using optical microscopy and scanning electron microscopy were analyzed. Coefficient of thermal expansion (CTE) and thermal conductivity (TC) were investigated depending on the process conditions

Keywords:

Composite Material, Hot-Pressing, Sintering, Thermal Conductivity (TC), Thermal Diffusivity, Thermal Expansion Coefficient

Affiliations:
Chmielewski M.-Institute of Electronic Materials Technology (PL)
Pietrzak K.-IPPT PAN
Kaliński D.-other affiliation
Strojny A.-Institute of Electronic Materials Technology (PL)

Conference papers
1.Pietrzak K., Kaliński D., Chmielewski M., Chmielewski T., Włosiński W., Choręgiewicz K., Processing of intermetallics with Al2O3 or steel joints obtained by friction welding technique, ECerS XII, 12th Conference of the European Ceramic Society, 2011-06-19/06-23, Stockholm (SE), pp.1-4, 2011
Abstract:

The development of technologies for joining advanced materials is connected with an introduction of new materials and new applications of their bonds, to work in ever more difficult conditions. One of possibilities of obtaining this type of joints is using the friction welding technique. This paper presents the results of joining intermetallics (Fe-Al and Ni-Al type) with steel (S235JR) and ceramics (Al2O3) using friction welding technique. The focus of the investigations was selecting: appropriate rotational speed (10000-25000rpm) of joining elements, welding pressure and time (1500-4500ms) of its application and swelling time (1000-7000ms). The paper presents the results of microstructure investigations, investigations of microhardness (perpendicularly to joint surface) and mechanical properties (tensile strength).

Keywords:

friction welding, intermetallics, microstructure of joints, microhardness, tensile strength

Affiliations:
Pietrzak K.-IPPT PAN
Kaliński D.-other affiliation
Chmielewski M.-Institute of Electronic Materials Technology (PL)
Chmielewski T.-other affiliation
Włosiński W.-other affiliation
Choręgiewicz K.-other affiliation
2.Pietrzak K., Jach K., Kaliński D., Chmielewski M., Morgiel J., Processing and Microstructure of Al2O3-Cu Composite Material Interpenetrating Network Type, Euro PM2011 Congress and Exhibition, 2011-10-09/10-12, Barcelona (ES), Vol.2, pp.1-6, 2011
Abstract:

Alumina/copper composites have been used where high thermal conductivity, high absorption and dissipation of heat, high resistance to thermal fatigue and good frictional wear resistance are required. This kind of composites may be applied in medicine, electronic and automotive industry. Both the physical and mechanical properties of this type of composites are strongly influenced by the properties of its individual constituents and, also, by the properties of interface layer between ceramic and metal. One of the solution, from the point of view of the best properties’ achievements (especially thermal, structural and shape stability), is the production of ceramic-metal composites with interpenetrating networks structure. They can be produced using porous alumina performs, which are infiltrated (pressure or pressureless) by molten metal or sintered with metallic powders. The subject of the presented paper is the development of the interpenetrating network Al2O3-Cu composites, processed by sintering porous ceramic perform (85 and 90% porosity) with copper powder. The paper presents the new developed technology, results of microstructure investigations, measurements of the selected physical and mechanical properties and the analysis of the influence of the processing conditions on the properties and interface morphology between ceramic and copper

Affiliations:
Pietrzak K.-IPPT PAN
Jach K.-Institute of Electronic Materials Technology (PL)
Kaliński D.-other affiliation
Chmielewski M.-Institute of Electronic Materials Technology (PL)
Morgiel J.-Institute of Metallurgy and Materials Science, Polish Academy of Sciences (PL)
3.Rojek J., Pietrzak K., Chmielewski M., Kaliński D., Modelowanie spiekania proszków metalicznych metodą elementów dyskretnych, KomPlasTech 2010, XVII Konferencja Informatyka w Technologii Metali, 2010-01-10/01-13, Białka Tatrzańska (PL), pp.1-8, 2010
Abstract:

W artykule przedstawiono badania doświadczalne oraz modelowanie numeryczne procesu spiekania proszków metalicznych. W części eksperymentalnej pracy badano ewolucję mikrostruktury oraz gęstości spieku w trakcie procesu spiekania. Jako metodę modelowania wybrano metodę elementów dyskretnych, w której zakłada się, że materiał jest reprezentowany przez liczny zbiór elementów dyskretnych (cząstek) o kształcie sferycznym oddziałujących między sobą. Modelowanie spiekania wymaga wprowadzenia oddziaływania kohezyjnego między cząstkami reprezentującego naprężenia powstające między ziarnami w trakcie spiekania. W artykule przedstawiono wstępne wyniki numeryczne pokazujące ewolucję naprężenia w trakcie spiekania między dwoma ziarnami spiekanego proszku.

Keywords:

spiekanie, metalurgia proszków, związki międzymetaliczne, modelowanie, metoda elementów dyskretnych

Affiliations:
Rojek J.-IPPT PAN
Pietrzak K.-IPPT PAN
Chmielewski M.-Institute of Electronic Materials Technology (PL)
Kaliński D.-other affiliation
4.Pietrzak K., Jach K., Kaliński D., Chmielewski M., Improving alumina wettabillity by modification of copper alloys chemical composition, PM2010, Powder Metallurgy World Congress and Exhibition, 2010-10-10/10-14, Florence (IT), Vol.2, pp.361-367, 2010

Conference abstracts
1.Rojek J., Nosewicz Sz., Pietrzak K., Chmielewski M., Kaliński D., Discrete element simulation of powder metallurgy manufacturing process of metal-ceramic composites, ECCOMAX 2012, 6th European Congress on Computational Methods in Applied Sciences and Engineering, 2012-09-10/09-14, Wiedeń (AT), pp.1-2, 2012
2.Nosewicz Sz., Rojek J., Pietrzak K., Chmielewski M., Kaliński D., Kačianauskas R., Discrete Element Modelling of Solid State Sintering Process of Metal-Ceramic Composite, SolMech 2012, 38th Solid Mechanics Conference, 2012-08-27/08-31, Warszawa (PL), pp.172-173, 2012
3.Rojek J., Nosewicz S., Pietrzak K., Chmielewski M., Kaliński D., Modelling of powder sintering using the discrete element method, CMM 2011, 19th International Conference on Computer Methods in Mechanics, 2011-05-09/05-12, Warszawa (PL), pp.241-1-2, 2011
4.Rojek J., Pietrzak K., Chmielewski M., Kaliński D., Discrete element modelling of powder sintering, SolMech 2010, 37th Solid Mechanics Conference, 2010-09-06/09-10, Warszawa (PL), pp.64-65, 2010
5.Rojek J., Pietrzak K., Chmielewski M., Kaliński D., Constitutive modelling of sintering processes using the discrete element method, Workshop on Constitutive Modeling in Applications for Industrial Processes, 2010-09-01/09-03, Kraków (PL), pp.1-2, 2010