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In this paper, new cost-effective platinum-free and flexible counter electrodes (CEs) for dye-sensitized solar cells (DSSCs) were reported. The ITO/PET CEs were produced using graphene films synthesized by CVD method and graphene flakes with addition PEDOT: PSS or PEDOT: PSS/PVP. The influence of mechanical stress arising from the bending of a flexible substrate on morphology, resistance of CEs as well as electrical properties of DSSCs was analyzed. The testing of these electrodes in DSSCs have demonstrated a power conversion efficiency of up to 3.95% to compare with the power conversion efficiency of 4.39% for DSSC with a standard Pt-based CE. After 100 bending cycles the electrodes demonstrated power conversion efficiency in range the 2.37–3.23% to compare with the power conversion efficiency of 2.08% for DSSC with a standard Pt-based CE. HRTEM investigation confirms the crystallographic structure of graphene. The obtained results demonstrate the possibility of replacing expensive platinum in DSCC by using graphene-based counter electrode.

The porous ceramic preforms were manufactured using the powder metallurgy technique. First, the start-up material (halloysite with the addition of carbon fibres as the pore-forming agent) was slowly heated to 800 °C and then sintered at 1300 °C. Degradation of the carbon fibres enabled the open canals to form. At the end of the sintering process, the porous ceramic material consisting mainly of two phases (mullite and cristobalite) was formed, without any residual carbon content. During infiltration, the liquid metal filled the empty spaces (pores) effectively and formed the three-dimensional network of metal in the ceramic. The cristobalite was almost entirely decomposed. In the areas of its previous occurrence, there are new pores, only in the ceramic grains. The mullite, which was formed from halloysite during annealing, crystallized in the Pbam orthorhombic space group, with the (3Al2O3·2SiO2) stoichiometric composition. The mullite structure does not change during the infiltration. The composite components are tightly connected. A transition zone between the ceramics and the metal, having the thickness of about 200 nm, was formed. The nanocrystalline zone, identified as γ-Al2O3, was formed by diffusing the product of the cristobalite decomposition into the aluminium alloy matrix. There is an additional, new phase, identified as (Mg,Si)Al2O4 in the outer parts of the transition zone.

The paper presents the research results on the microstructure, mechanical and tribological properties of coatings deposited by cathodic arc evaporation methods on the X40CrMoV5-1 hot work tool steel substrates as well as the possibility to employ the finite element method for evaluation of stresses in the investigated coatings. The tests were carried out on CrAlSiN and CrN coatings. The coatings demonstrated a dense cross-sectional morphology as well as good adhesion to the substrate. The critical load LC2 lies within the range 54–55 N, depending on the coating type. The investigated coatings have the potential to increase the service life of an extrusion die by orders of magnitude as compared with uncoated steel.

To minimise reflection from the flat surface, the multicrystalline silicon wafers were textured. This means creating a roughened surface so that incident light may have a larger probability of being absorbed into the solar cell. Due to grains of random crystallographic orientation, most of the texturing methods used for monocrystalline silicon are ineffective in case of multicrystalline silicon. Therefore, in the present paper a new approach to surface texturisation was developed. Texturisation of multicrystalline silicon wafers was carried out by means of laser surface treatment. Then, a special etching procedure was applied to remove laser-damaged layer. The reflectance of produced textures was measured by PerkinElmer Lambda spectrophotometer with an integrating sphere. The topography of laser-textured surface was investigated using ZEISS SUPRA 25 and PHILIPS XL 30 scanning electron microscopes. The laser treatment and etching in alkaline solution ensured obtaining texture of regular structure that was insensitive to random crystallographic orientation of different grains. The laser processing parameters were adjusted by performing a number of experiments for different values of processing parameters. It is a new approach to texturisation problem of multicrystalline silicon.

The paper presents the effect of HPD laser treatment on the microstructure and selected properties of the PVD CrN, (Ti,Al) and Ti(C,N) coatings deposited onto hot-work tool steel substrates. The microstructure and surface topography of the investigated samples are characteristic of the diversified morphology connected with the applied laser beam power. Employment of laser beam at 0.7 kW power to the laser treatment of samples with Ti(C,N) coatings causes clear coating adhesion growth because of the diffusive processes induced by heat release. Because of the higher value of the (Ti,Al)N absorption coefficient one can state that the observed substrate materials change and finally coatings destruction in case of those samples is the most noticeable. The moderate effect of the laser beam treatment of the hot-work tool steel with the PVD coating was observed for CrN coatings. However, for laser beam power above 0.5 kW differences in the thermal expansion coefficients of the substrate materials and coatings generate coating crackings.

The paper presents investigation of the Ti(C, N) and (Ti, Al)N gradient coatings deposited with use of the cathodic arc evaporation CAE-PVD method on sintered tool materials: cemented carbides, cermets and Al 2 O 3 + TiC oxide tool ceramics. The investigation includes the metallographic analysis on the scanning electron microscope (SEM). The X-ray qualitative microanalysis and surface distribution analysis of elements in the investigated materials were made using the EDS X-ray energy dispersive radiation spectrometer. Moreover the investigation includes analysis of the mechanical and functional properties. Tests of the coatings adhesion to the substrate material with use of the scratch test and surface roughness tests were done both before depositing the coatings and after completing the PVD process. It has been showed that investigated materials are characteristic of the dense, compact structure and their fracture surface topography attests to their high brittleness, characteristic especially for the oxide ceramic materials. The results of roughness and microhardness tests confirm the advantages of the multicomponent (Ti, Al)N and gradient Ti(C, N) coatings. As results of the examination of coating microhardness it has been found that multicomponent and gradient coatings on the investigated materials causes the 35–76% increase of microhardness value. Depositing the wear resistant coatings onto the tool cemented carbide, cermet, and oxide tool ceramics results in a significant increase of the surface layer microhardness, contributing most probably in this way in machining to the decrease of the wear intensity of cutting tools’ flanks made from cemented carbide, cermet and tool ceramics.

Results of polymer matrix hard magnetic composite materials with particles of powdered rapid quenched Nd-Fe-B strip are presented in this paper. Influence of additional materials on magnetic, mechanical and electrical properties of composite materials was studied. The composite without additions revealed good magnetic properties. With addition of soft magnetic materials—iron, the coercive force decreased while remanence of composite was almost not influenced. The addition of steel reduces both coercive force and remanence. However addition of metallic powders improves mechanical properties of the composite materials.

The paper presents a neural network model for evaluation of the magnetic/mechanical properties and the rate of corrosive wear of the polymer matrix hard magnetic composite materials with particles of the powdered rapid quenched Nd–Fe–B strip with addition of metallic powder: iron, aluminum, CuSn10 type cast copper–tin alloy and X2CrNiMo17-12-2 high-alloy steel. Simulation approach to model the magnetic/mechanical properties in function of the chemical composition employing a neural network technique was proposed. A neural network model of corrosion wear was established based on the research results from the investigations carried out in two corrosive environments. Simulation approach to model the corrosive wear in function of the chemical composition, nature of the corrosive environment and the test duration was proposed. The obtained results indicate that the developed neural networks are able to generalize which justified using these models to the simulation of magnetic/mechanical properties and corrosive wear of hard magnetic composite materials.

Results are presented of the chemical composition, qualitative and quantitative examinations of the test pieces’ microzones and of the observations of transverse fractures surfaces of the modified casting magnesium alloys based on the EN-MCMgAl9Zn1 alloy. Presence of the following casting alloys main elements was confirmed in the analysed test pieces: magnesium, aluminium, manganese and zinc, constituting the structure of the α solid solution with the Mg17Al12 phases precipitations, as well as eutectics and phase AlMnFe, Mg2Si. Fractures of the investigated alloys were of a mixed nature. The investigation is carried out to testy the influence of the chemical composition and precipitation processes on the structure and mechanical properties of the magnesium cast alloys with different chemical composition in its as-cast alloys and after heat treatment.

In this work the derivation analysis techniques is applied for the preparation of ACAlSi7Cu alloy thermal characteristic, and assessed influence of cooling rate for characteristic transformations during the crystallizations. Alloys were cooled with three cooling rate: 0.2, 0.5 and 1 °C/s. Rise of the cooling rate is influenced on a dendrite phase nucleation point which has an effect on a solid fraction. In this case alloys are much more uniform. The changes of crystallization temperature at the end of the process are not observed during the rise of the cooling rate. The neural networks were used for modeling of the ACAlSi7Cu alloy crystallization process cooled with different cooling rate.

In this work effect of cooling rate on the size of the grains, SDAS, size of the β precipitation and thermal characteristic results of AC AlSi7Cu2 cast alloy have been described. The solidification process was studied using the cooling curve and crystallization curve at solidification rate ranging from 0.16 °C s−1 up to 0.71 °C s−1. It was determined that the higher solidification rate increases the aluminum dendrite nucleation temperature and solid fraction at the dendrite coherency point, which implies that mass feeding is extended. In addition, it was observed that the non-equilibrium solidus temperature and the size of the grains, SDAS and size of the β precipitation constituent decreases when the solidification rate increases. This work demonstrates that the thermal and chemical modification of the eutectic silicon can be quantitatively assessed by analysis of the cooling curve thermal characteristics.

This paper presents the results about remelting laser parameters on the structure and properties of the surface of the 32CrMoV12-28 hot work steel, using the high-power diode laser (HPDL). In the work, structure changes were studied, especially its fragmentation. Also hardness investigation of the different remelting areas was performed. The purpose of this work was also to determine the laser treatment parameters, particularly of the laser power to achieve good layer hardness for protection of this hot work tool steel from losing their work stability and to make the tool surface more resistant to action in external conditions. For alloying, the titanium carbide and tungsten carbide powders were used. Goal of this work was also to determine technically the technological conditions for remelting of surface layer with HPDL. The remelted layers which were formed on the surface of investigated hot work steel were examined metallographically and analyzed using a hardness testing machine. Two phases of carbides, TiC and WC, were observed.

The subject of the present paper is to design the technique of laser texturization for solar cells made of multicrystalline silicon and improve understanding of the interaction between laser light and workpiece. We explore how different transverse modes influence laser surface treatment and examine some details related to laser multimodal operation. Since constant increase in global production of photovoltaic power can be observed the new technologies for manufacturing solar cells of improved efficiency are developed. One of the most important factors influencing cells performance is reflectivity of its front side. Consequently, new methods for efficient reduction of reflectance are searched. One of the crucial stages which is carried out to increase solar radiation absorption is surface texturization. It is brought under well control for solar cells made of monocrystalline silicon. However, from the market point of view the reduction of production costs has essential meaning. As a result, the market share of multicrystalline cells systematically grows since the base material is approximately twice cheaper compared to monocrystalline silicon. But on the other hand, texturization methods used for monocrystalline silicon are ineffective in the case of multicrystalline silicon. Thus, it seems to be very interesting to investigate new alternative methods for effective texturization of multicrystalline silicon. One of the promising technologies is laser processing which is the subject of present paper.

This paper presents the material and technological solution which makes it possible obtaining of soft and hard magnetic composite materials: nanocrystalline material–polymer. For fabrication of composite materials the following powders were used: soft magnetic material (Fe 73.5 Cu 1 Nb 3 Si 13.5 B 9 ) and hard magnetic material (Nd 14.8 Fe 76 Co 4.95 B 4.25 ). Polymer was used as the matrix (2.5 wt.%). Advanced composite materials were compacted by the one-sided uniaxial pressing. The complex relationships among the manufacturing technology of these materials, their microstructure, as well as their mechanical and physical properties were evaluated. Materialographic examination of powders morphology and the structure of composite materials were made. Composite materials show regular distribution of magnetic powder in polymer matrix. Examination of mechanical properties shows that these materials have satisfactory compression strength. Composite materials show lower magnetic properties in comparison with magnetic powder but their geometrical form allows extending their applications. The paper shows also the possibilities of these magnetic materials application. The advantage of the bonded composite materials is their simple technology, possibility of forming their properties, lowering manufacturing costs because of no costly finishing and lowering of material losses resulting from the possibility of forming any shape. The manufacturing of composite materials greatly expand the applicable possibilities of nanocrystalline powders of magnetically hard and soft materials.

Laser surface modification, although for a number of years, is a technology, which is still in its infancy. This paper presents the results of laser alloying influence on structure and properties of the surface of the X38CrMoV5-3 hot work steel, carried out using the high-power diode laser (HPDL). Niobium carbide powder was used for alloying. In the paper, investigation results are presented of the melting and alloying of ceramic particles on the surface layer. Results of the metallographic examinations qualitative X-ray phase analysis and the mechanical properties are presented.

The paper emphasises the very significant role of materials selection for design and manufacturing processes of new needed products, having the highest attainable quality and performance at the optimum and possibly the lowest cost level. The engineering design processes cannot be set apart either from the material design, being more and more often computer aided, or the technological design of the most suitable manufacturing processes. The review of the multi-millennia long history of human civilisation indicates that the significant increase of the level of living and production is connected more often with the launching of new material groups with the properties better and better adjusted to real requirements of customers getting more sophisticated nearly each day, and also the launching of the technological processes which are relevant to them. The given reasons enable to forecast that the future of the market and products with the required properties, which appear on the market, are inseparably connected with the development of materials science and engineering. Two main priorities can be specified in that area, that is: the continuous improvement of existing materials, and technological processes and the development of materials and technological processes ensuring environment protection or/and improving conditions and extending of human life. The paper includes also the description of the world developmental trends in that area in the first decades of the 21st century. The fundamental aim of materials science and engineering is materials selection ensuring required functions and application properties of products, which are manufactured out of them. The tasks of that field of science in priority spheres of the world development are determined. Directions of activities of materials science and engineering ensuring the achievements of strategic aims of the developments of societies include materials design, computational materials science, advanced analytical methods, manufacturing and processing, nano-, smart and biomimetic materials are included. It is concluded that there is a humanistic mission which stands at the engineering circle, especially associated with materials and manufacturing engineering and its aim is to make products and consumer goods, deciding directly about the level and quality of human life, available to people and it is also mentioned that current financing of scientific researches especially in the mentioned fields of science gives a chance to achieve modern technological development and to ensure prosperity of societies in the future.

The paper presents results of merging the thermal and mechanical nanocrystallization processes of the Fe73.5Cu1Nb3Si13.5B9 alloy, and further examination of the structure, as well as the magnetic and mechanical properties of powders obtained in this way and also of composites developed by their binding with polyethylene (PEHD). The composites were obtained in the one-sided uniaxial pressing at the temperature of 170 °C under the pressure of 350 MPa.

In this paper, results on laser and plasma powder surfacing technology of marine engine valve heads faying face made of X40CrSiMo10-2 alloy steel are presented. It was shown that the cobalt-based powders provide high quality deposits, but the process of HPD laser surfacing ensures higher precision of control the quality and shape of the deposits and also the heat input of surfacing process (dilution of the deposits), compared with PTA surfacing process.

Investigations include alloying the X40CrMoV5-1 hot-work tool steel surface layer with the tungsten carbide, using the high-power diode laser (HPDL). The structural mechanism was determined of surface layers development, effect was studied of alloying parameters, gas protection method, and thickness of paste layer applied onto the steel surface on structure refinement and influence of these factors on the mechanical properties of surface layer, and especially, on its hardness, abrasive wear resistance, and roughness. The remelted zone structure is characterised by the significant martensite dispersion with its lathes length several times shorter than those of those developed during the conventional quenching. Martensite twining occurs in some locations, retained austenite, and very fine precipitations of the M6C and M7C3 type carbides are observed as broken network on dendrite boundaries, as well as the high-dispersive ones inside of certain grains. The fine-grained martensite structure is responsible for hardness increase of the alloyed layer. It has the important cognitive significance and gives grounds to the practical employment of these technologies for forming the surfaces of new tools and regeneration of the used ones.

In this communication, we present the powder injection moulding (PIM) of HS12-1-5-5 high-speed steel parts using a wax-HDPE based binder. The injection moulding process of the feedstock (68 vol.% of metal) has been optimized to obtain high quality green parts. The elimination of organic binder was carried out by thermal debinding under inert atmosphere. In order to keep carbon in the sample that could improve the sintering process, incomplete debinding were performed between 450 and 500 °C. In this study, we have studied the effect of different atmospheres on the debinding process. Debinding was performed under nitrogen and argon. The specimens were sintered at temperatures between 1200 and 1300 °C with steps of 10 °C in following mixture N 2 –10% H 2 atmosphere. The PIM parts present higher density than those obtained by conventional PM.

The tribological properties of the multi-layer PVD and CVD coatings deposited onto the Si 3 N 4 nitride tool ceramics are compared in the paper in relation to the fundamental mechanical properties like hardness, adhesion. The inserts made from Si 3 N 4 were multilayer coated in the PVD process with the TiN + multiTiAlSiN + TiN, TiN + TiAlSiN + TiN, and TiN + TiAlSiN + AlSiTiN coatings and in the CVD process with the TiC, Ti(C, N), Al 2 O 3 and TiN. Additional investigations were carried out to compare coatings obtained in this way on inserts from various manufacturers offering the nitride tool ceramics with the CVD coatings based on the Al 2 O 3 and TiN layers. Basing on the tribological test made with the “pin-on-disk” method in respect to the hardness and adhesion investigations the correlation was revealed between these two properties. Machining tests results and roughness tests results for the machined grey cast iron surface are also presented. The CVD coatings demonstrate high abrasion resistance in comparison with the PVD ones, whose adhesion to the nitride ceramics is low.

The paper presents a project dedicated to development of an expert system prototype for selection of the appropriate coating type and its technology, depending on the intended application and working conditions. A number of crucial factors are taken into account, like intensity of use, coated element shape, required colour and shine, roughness, cost and others. Final selection of the candidate coating is carried out using the weighted total taking into account the important coating feature values and their relevant weights, reflecting their importance for coating selection. The expert system prototype was developed using Exsys Professional shell.

Investigations of composite materials based on EN AW-2124 aluminum alloy reinforced with the BN or Al 2 O 3 particles with various weight ratios of 5, 10 and 15% are presented. Powders of the starting materials were mixed in the laboratory vibratory ball mill to acquire the uniform distribution of reinforcement particles in the matrix material. The components were initially compacted at cold state in a die with the diameter of O 26 mm in the laboratory vertical unidirectional press—with a capacity of 350 kN. The obtained P/M compacts were heated to a temperature of 480/500 °C and finally extruded—with the extrusion pressure of 500 kN. Bars with a diameter of 8 mm were obtained as the end product. Based on the microstructural examinations of the obtained composite materials, the uniform distribution of the reinforcing particles in the aluminum matrix was revealed. Hardness tests, static tensile tests and the compressive tests made it possible to demonstrate that all these properties change along with the reinforcing particles concentration change. As an example, hardness increased from 89 HV1 for the material without the reinforcing phase to 123 HV1 for 15% of BN, and the ultimate compressive strength decreases along with the increase of the reinforcing phase fraction from 667 MPa for 5% to 472 MPa for 15% of BN.

In this paper, a computer aided methodology of classification of flaws, which are formed in aluminium alloys during production of elements for car engines with the low-pressure casting method is presented. The flaw identification was performed on the basis of digital recorded data registered by the use of X-ray image analysis method. In order to solve this problem, an elaborated methodology and related computer programmes for X-ray images analysis, as well as the preparation of entrance data for neuronal networks and also the quality cast control were used. The classification results of the best type of every network investigated are presented. Analysing a number of correct classifications of pointed out test data, the classifying problems are evaluated.

The paper presents investigation results of structure and properties of the coatings deposited with the PVD and CVD techniques on cutting inserts made from the Al 2 O 3 + ZrO 2 oxide tool ceramics. The investigation includes the metallographic analysis on the scanning electron microscope and chemical composition, texture and macro-stresses analysis. The investigation includes also analysis of the mechanical and functional properties of the material: substrate hardness tests and microhardness tests of the deposited coatings, surface roughness tests, evaluation of the adhesion of the deposited coatings and cutting properties of the investigated materials.

The paper presents investigation results of structure and properties of the coatings deposited with the PVD and CVD techniques on cutting inserts made from the Al 2 O 3 + TiC oxide tool ceramic. The investigation includes the metallographic analysis on the transmission and scanning electron microscope, chemical composition analysis as well as the analysis of the mechanical and functional properties of the material. Tests were carried out on the multipoint inserts made from the Al 2 O 3 + TiC oxide ceramics, uncoated and coated with multi-layer hard wear resistant coatings composed of TiN, TiCN, TiAlN, TiAlSiN and Al 2 O 3 layers with PVD and CVD processes. It was demonstrated that adhered closely to each other were characterized by good adhesion to the substrate. It was demonstrated, basing on the technological cutting tests of grey cast iron, that putting down onto the tool ceramics the thin anti-wear coatings in the PVD and CVD processes increases their abrasion wear resistance, which has a direct effect on extending the tool edge life. Basing on the roughness parameter R a of the machined cast iron surface after the cutting tests, improvement was revealed of the machined material properties, cut with coated oxide ceramics compared to material machined with the uncoated tools.

The paper presents investigation results of the effect of deposition parameters on chemical and phase composition, structure, texture, thickness, micro-hardness and fractal dimension of surface topography of the two-layer Ti + TiC coatings obtained by magnetron sputtering in the vacuum furnace onto the ASP 30 sintered high speed steel. The fractal dimension value of surface topography of analysed coatings was determined using the projective covering method basing on investigation results in the atomic force microscope.

The paper presents results of the investigation of the structure, mechanical properties and tribological tests of CrN, TiN, TiN/(Ti,Al)N PVD coatings deposited onto X37CrMoV5-1 type hot work steel. Thin hard coatings are today employed in vast number of applications for reducing friction and wear of tools and mechanical components, however there are still big interest to improve tools used in hot-working process e.g. metal die casting, hot extrusion and hot forging as well as glass and plastics processing. The goal of this investigation is to determine usefulness of that coatings type deposition in order to improve wear resistance of tools made from hot work steels. Based on the results of metallographic examinations of microstructure it was shown that TiN, TiN/(Ti,Al)N coatings have compacted, columnar structure while CrN coating has compacted submicrocrystalline structure. According to the observations made after scratch test we found the highest adhesion for CrN monolayer coating and the lowest one for multilayers TiN/(Ti,Al)N coating. Moreover it was found that failure mechanism during scratch test in all investigated coatings begins with multiple spallings located on the scratch edges followed by cracking and total delamination of coating. The wear resistance was investigated by pin-on-disc method performed in room and elevated to 500 °C temperatures. We found that the lowest wear at certain conditions in both room and elevated temperatures shows TiN monolayer coating what can be connected with their good adherence to the substrate materials as well as the highest hardness.

In the paper an optimisation method for the designing of chemical composition of high-speed steels (HSS) based on genetic algorithms (GA) is presented. The complex optimisation criterion was assumed comprising maximising secondary steel hardness with simultaneously minimising cost of material. Results of the numerical simulation show that genetic algorithm-based optimisation of steel chemical composition is effective and very useful in designing of the new metallic materials.

Structure, magnetic and mechanical properties of the nanocrystalline composite material of the SILAME ® type were tested. The composite material was obtained by solidification of the nanocrystalline powder obtained in the high-energy grinding of the initially crystallized Co 68 Fe 4 Mo 1 Si 13.5 B 13.5 amorphous ribbon with the silicon polymer. The metallic powder was mixed with the silicon polymer in a different weight ratio and next the effect of Co 68 Fe 4 Mo 1 Si 13.5 B 13.5 powder weight ratio on the magnetic and physical properties of the composite was investigated. Moreover, the powder was subjected to uniaxial compression, in which the pastille was obtained with the density of ρ = 5.78 g/cm 3 was subjected to the isothermal annealing after examining its magnetic properties. Next, the magnetic properties were compared with the obtained powder, powder after compression, and the compressed powder after annealing. In addition the effect of the high-energy milling conditions were presented on the soft magnetic properties of powder material and the influence of the silicon matrix on the magnetic and mechanical properties of the composite cores.

The paper presents the possibility to employ the finite element method for evaluation of stresses in the Ti + TiN coating obtained in the magnetron PVD process on the sintered high-speed steel of the ASP 30 type, taking into account their deposition conditions. FEM was used to evaluate stress error in the simulated model. Computer simulation results were compared with the experimental results of stress measurement in the analysed coatings. Computer simulation of stresses was carried out in ANSYS environment, using the FEM method and the experimental values of stresses were determined basing on the X-ray diffraction patterns.

Comprehensive structure and properties investigation results of the multi-layer, multi-component physical vapour deposition (PVD) and chemical vapour deposition (CVD) coatings developed on the Si 3 N 4 nitride tool ceramics substrate are presented in the paper. The detailed results are presented of examinations carried out on the scanning and transmission electron microscopes, as well as of the mechanical properties and tribological tests of the investigated coatings. Examinations of the chemical compositions of the deposited coatings were also carried out using the X-ray energy dispersive spectrograph EDS, glow-discharge optical emission spectroscope GDOS, and using the X-ray diffractometer. Machining tests of the grey cast iron and nickel alloy were made to analyse in detail the investigated multi-edge cutting inserts. The inserts made from Si 3 N 4 were coated in the PVD process with the TiN + multiTiAlSiN + TiN, TiN + TiAlSiN + TiN, TiN + TiAlSiN + AlSiTiN type multi-component coatings and in the CVD process with the coatings based on the combination of the TiC, TiN, Ti(C,N) and Al 2 O 3 layers.

The paper presents the characteristics of the protective polymer, lacquer, and metal coatings put down onto the hard magnetic composite substrate with the polymer matrix, reinforced with the Nd–Fe–B particles with additions of metal powders. Examinations of the coatings’ structures were made with the scanning electron microscopy method. Hardness, thickness, and adhesion tests of the deposited coatings were also made. It was found out that the protective coatings are characteristic of the uniform deposition on the entire surface and of the same thickness all over their area. These coatings are characterised by a compact structure with no visible delaminations and defects. Polymer coatings demonstrate higher hardness compared to the lacquer ones. The highest hardness of 350s is characteristic of the polyester polymer coating. It was found that the highest adherence of 8.4 MPa is characteristic of the polyester–epoxy coating, whereas, the lowest adherence is displayed by the phthal-urethane coating—5.0 MPa. The paper presents also the corrosive wear of the hard magnetic composite materials with the polymer matrix, reinforced with the Nd–Fe–B particles from the rapid quenched strip, sintered Nd–Fe–B magnets, and composite materials coated with the protective polymer, lacquer, and metal coatings. The corrosive resistance values in the water environment and in the 5% NaCl solution environment were determined. It was found out that the composite magnets with the polymer matrix demonstrate better corrosive resistance than the sintered magnets; whereas, the best protection from the corrosive environment is provided by the polymer coatings. The neural network model for evaluation of the rate of corrosive wear of the polymer matrix hard magnetic composite materials with addition of metallic powder was established based on the research results from the investigations carried out in two corrosive environments. Three types of input data were used in the investigation: the contribution of the added powder, the nominal variable that defined the corrosive environment and the time duration of the test. The percentage corrosive wear of the surface was the output produced from such input data.

Investigations of composite materials based on EN AW-2124 aluminum alloy reinforced with the Al2O3 particles with various weight ratios of 5, 10, and 15% are presented. Powders of the starting materials were mixed in the laboratory vibratory ball mill to acquire the uniform distribution of reinforcement particles in the matrix material. The components were initially compacted at cold state in a die with the diameter of ∅26 mm in the laboratory vertical unidirectional press with a capacity of 350 kN. The obtained P/M compacts were heated to a temperature of 480–500 °C and finally extruded with the extrusion pressure of 500 kN. Bars with a diameter of 8 mm were obtained as the end product. Based on the microstructural examinations of the obtained composite materials, the uniform distribution of the reinforcing particles in the aluminum matrix was revealed. Hardness tests and the ultimate compressive strength tests made it possible demonstrate that both these properties change along with the reinforcing particles concentration change. As an example, hardness increased from 89.27 HV1 for the material without the reinforcing phase to 123.4 HV1 for 15% Al2O3, and the ultimate compressive strength decreases along with the increase of the reinforcing phase fraction from 798 MPa for 5% to 663 MPa for 15% Al2O3. Results of the corrosion tests, determined using the potentiodynamic method in the 3% water solution of NaCl indicate that corrosion of the investigated composite materials depends on the volume fraction of the reinforcing particles. It was found out, based on the determined anode polarisation curves that the investigated materials are susceptible to pitting corrosion. Moreover, investigation results indicate that the composite materials reinforced with the ceramic particles with the portions of 5 and 10% are characteristic of a higher corrosion resistance in the selected environment, compared to the matrix material, whereas at the 15% portion this resistance it worse, the anode digestion current grows.

The paper presents investigation results of tribological properties of the coatings deposited with the PVD and CVD techniques on cutting inserts made from the Al 2 O 3 + SiC (w) oxide tool ceramic. Tests were carried out on the multipoint inserts made from the Al 2 O 3 + SiC (w) oxide ceramics, uncoated and coated with gradient, mono-, multilayer and multicomponent hard wear resistant coatings composed of TiN, TiCN, TiAlN, TiAlSiN and Al 2 O 3 layers with PVD and CVD processes. Substrate hardness tests and microhardness tests of the deposited coatings were made on the ultra-micro-hardness tester. It was demonstrated, basing on the technological cutting tests of spheroidal cast iron, that putting down onto the tool ceramics the thin anti-wear coatings in the PVD and CVD processes increases their abrasion wear resistance, which has a direct effect on extending the tool edge life. Basing on the roughness parameter R a of the machined cast iron surface after the cutting tests, improvement was revealed of the machined material properties, cut with coated oxide ceramics compared to material machined with the uncoated tools.

The paper presents investigation results of the structure and corrosion resistance of the CuZn40Pb2 brass deposited by PVD process with the thin multilayer Ti/CrN, Ti/ZrN, Ti/TiAlN, TiAlN/Mo coatings. The corrosion tests were made in a 1 M HCl solution. It was found out that coatings deposited by PVD method on the brass substrate improve significantly its corrosion resistance. It has been demonstrated that the increase of the number of layers results in a significant increase of the corrosion resistance. The best results were obtained for the multilayer Ti/ZrN and Ti/CrN coatings.

The method presented in the paper makes it possible to determine the mass concentrations of the alloying elements for steels with the required curve of hardness changes versus cooling rate. Search for the optimum chemical composition is carried out in two stages. The first stage consists in preparing the data file consisting of chemical compositions of steels and calculated curves of hardness change versus cooling rate. Hardness of steel cooled from the austenitising temperature is calculated with the model using the artificial neural networks. At the second stage, the chemical composition of steel is searched for the closest to the assumed criterion.

Structure and mechanical properties of the HS12-1-5-5 type high-speed steels manufactured by powder injection moulding and with the pressureless forming were investigated and compared in the project. Basing on the structure examinations, occurrences of big spherical pores in the pressureless formed test pieces were revealed, that could not be eliminated in the debinding and sintering processes. The specimens fabricated with the powder injection forming method are characteristic of the higher density and uniform distribution of the high-speed steel powder in the binding agent matrix. In addition, employing the bicomponent binding agent in the form of paraffin and polyethylene made cutting the debinding and sintering time possible by about 10 h in comparison to manufacturing the steel with the pressureless forming method. Hardness tests in the as quenched state of the HS12-1-5-5 type steel specimens have demonstrated that the pressureless formed steels display lower hardness compared to steels manufactured with the PIM method. This is, undoubtedly, caused by a higher carbon concentration, which lowers the Ms and Mf temperatures of the martensitic transformation and increases the contents of the retained austenite. Yet, pressureless forming has its advantages. This method does not require practically any additional equipment apart from the furnace for thermal debinding of the binding agent and for sintering. Moreover, specimens formed with the pressureless method have lower sintering temperature and higher density.

In work showed, that producing many and multiple layers of type TiN + mono- or gradient(Ti, Al, Si)N + TiN and TiN + multi(Ti, Al, Si)N + TiN in CAE (cathodic arc evaporations) process (method PVD) on tools produced from cemented carbides and cermets puts into port influences on enlargement of hardness of coatings, deciding about rise of property useful tools cutting off covered with coatings of system TiN + mono- or multi(Ti, Al, Si)N + TiN, in comparison with produced on these oneself parched tool materials, but not covered or covered with straight coatings. Microhardness of the deposited coatings were examined using the scratch test method. Results of the continuous machining of the C45E steel with the indexable and disposable inserts are presented along with the roughness test results of the machined steel surface. Metallographic examinations were made of the substrate structures and coatings on the electron microscope (TEM and SEM), as well as of the wear type resulting from machining tests.

This paper presents the material and technological solution which makes it possible obtaining of the nanocrystalline, ferromagnetic powder material of Fe73.5Cu1Nb3Si13.5B9 alloy after its thermal nanocrystallization with its succeeding high-energy milling. Another aspect was developing the technology to obtain the nanocrystalline composites made by binding the obtained powder material with the high density pressureless polyethylene (PEHD) with the controlled ferromagnetic and mechanical properties. The module for their forming has been designed. The module consists of the die enclosed in the heater-coupled testing machine set up for compression test. It was possible, with the stand set up like that to compact the fabricated components (one-sided uniaxial pressing). The high density pressureless polyethylene powder was used as binder with mass fraction of 2.5, 5.0, and 7.5%.

The paper deals with the combined influence of the thermal nanocrystallization temperature and time and the milling time on the properties of the nanocrystallization process and the structure of powders based on METGLAS (metallic glass). Thermal treatment of Fe 78 Si 13 B 9 metallic glass was carried out for 1 h at the temperature range of 100–600 °C with 50 °C temperature steps. The heat treated material was then processed by high-energy milling. It was shown, that the use of a combination of thermal nanocrystallization and high-energy milling produced metallic glass-based nanocrystalline powders containing Fe-α, Fe 3 B and Fe 2 B crystallites in the amorphous matrix. Then, the nanocrystalline powders were used to construct composite toroidal cores.

The paper presents results of the structural examinations, tests of mechanical and working properties of thin anti-wear coatings of the TiN/TiAlSiN/TiN type, deposited in the PVD process onto the substrate from the tool cermets and sintered carbides. Structural examinations are presented of the applied coatings and their substrate made on the scanning electron microscope and on the light microscope. Evaluation of the adhesion of the deposited coatings onto the sintered carbides and cermets was made using the scratch test. The lowest force LC called the critical load was determined based on the acoustic emission value (AE), at which loss of the coating adhesion to the substrate occurs. Cutting properties of the investigated materials were determined based on the technological continuous cutting tests of the C45E steel. Width of the wear band on the tool flank VBmax = 0.2 mm was assumed as the cutting edge wear criterion for finishing. Substrate hardness tests and micro-hardness tests of the deposited coatings were made on the ultra-micro-hardness tester at 70 mN load. Surface roughness tests were also made before depositing the coatings and after completing the PVD process.

Investigations carried out in this work reveal that the experimental high speed steels of the HS6-5-2 and HS12-1-5-5 types pressureless formed from the polymer-powder slurry and heat treated are characteristic of the high abrasion wear resistance. These steels can be austenitized at a lower temperature compared to the commercial steels, because of the high concentration of carbon remaining after the binder degradation, lowering the solidus temperature. Tribological tests of the experimental steels confirm the sense of employing the pressureless high speed steel forming from the polymer-powder slurry, and especially their sintering in the protective gases atmosphere N2–5% H2, due to which nitrogen diffusion occurs and fine carbonitrides of the MX type develop, improving abrasion wear resistance of these steels. The HS12-1-5-5 grade experimental steel made by pressureless forming from the polymer-powder slurry, for which the material volumes removed during the pin-on-disc and pin-on-plate tests are about 0.01 and 0.005 mm3, respectively, is characteristic of the highest abrasive wear resistance.

This elaboration presents the influence of casting method and anodic treatment parameters on thickness and structure of an anodic layer formed on aluminium alloys. As test materials it was employed the aluminium alloys AlSi12 and ALSi9Cu3, supplied by the Dutch company MIFA b.v., in which casting process and anodic treatment of samples were carried out also. It was presented herein grindability test results and metalographic examination, as well. Hardness of non-anodised alloys with those ones subjected to anodising process were compared.

It has been demonstrated in the paper that the deposition of the multi-layer and multi-component coatings with the PVD technique using cathode arc evaporation CAE process, on tools made from cemented carbides, results in the increasing of coating hardness and the improvement of their adhesion to the substrate, comprising with the single- or multi-layer coatings deposited using the PVD or CVD methods on the same substrate materials, deciding improvement of the working properties of cutting tools coated with the TiN + mono or multi (Ti, Al, Si)N + TiN system coatings, compared with coatings developed on the same sintered tool materials, but uncoated or coated with simple coatings. The paper presents the results of the structural examinations, mechanical tests and working properties of thin wear resistant coatings of the TiN + mono or multi (Ti, Al, Si)N + TiN type, deposited onto the substrate from the cemented carbides. Structural examinations of the applied coatings and their substrate was made using the SEM and on the light microscope. The evaluation of the adhesion of the deposited coatings onto the cemented carbides was done using the scratch tester. Cutting properties of the investigated materials were determined based on the technological continuous cutting tests of the C45E steel. Microhardness tests of the deposited coatings were made on the ultra-microhardness tester. Surface roughness tests were done either before depositing the coatings and after completing the PVD process.

The results of the research concerning the influence of the thermal and mechanical nanocrystallization on the structure and magnetic properties of the powders obtained from the Fe73.5Cu1Nb3Si13.5B9 alloy are presented in the paper. The structure and magnetic properties of the nanocomposites obtained by combining the Fe73.5Cu1Nb3Si13.5B9 alloy with the polyethylene powder of high density (PEHD)—10 wt.% were also investigated in the paper. The composites were obtained in the one-sided, uniaxial pressing process in the temperature of 170 °C and the pressure of 200 MPa.

The paper presents the investigation results of the multi-layer CVD coatings on the substrate from the Si 3 N 4 nitride ceramics. Examination results are presented from the scanning electron microscope, test results of the adhesion of the coatings put down onto the substrate, as well as microhardness and roughness test results. Chemical composition examinations of the developed coatings were also carried out using the EDS X-ray dispersive energy spectrometer and the X-ray diffractometer. The Si 3 N 4 inserts were multi-layer coated in the high-temperature CVD process with the combination of the TiC, Ti(C,N), Al 2 O 3 and TiN coatings, which were further compared with the commercially available inserts of various manufacturers offering the combination of the CVD coatings of the Al 2 O 3 + TiN type. It was demonstrated that all double- and multi-layer coatings were characterized by a very good adhesion to the substrate. The microhardness tests revealed that the insert with the TiN + Al 2 O 3 coating had the highest hardness. It was found out also that roughness of the investigated specimens grows by about 0.3 μm on an average after putting down the coatings with the CVD method. Based on the metallographic examinations carried out it was found out that the multi-layer CVD coatings were uniformly put down onto the substrate and their particular layers adhere closely to each other. Results of the X-ray quantitative phase analysis confirm presence of phases originating from coatings and substrate. Analysis of the chemical composition – EDS – confirms presence of both titanium and aluminium, as well as of oxygen, carbon, and nitrogen in the investigated coatings and also of silicon and nitrogen in the investigated substrate.

Magnesium and magnesium alloys are primarily used in aeronautical and automobile industry in large variety of structural characteristics because of their favorable combination of tensile strength (160–365 MPa), elastic modulus (45 GPa), and low density (1740 kg/m3), which is two-thirds that of aluminum. Magnesium alloys have high strength-to-weight ratio (tensile strength/density), comparable to those of other structural metals. Application, structure and mechanical properties of selected magnesium alloys were investigated.

Comprehensive structure and properties investigation results of the multilayer, multi-component PVD coatings developed on the Si3N4 nitride tool ceramics substrate are presented in the paper. The detailed results are presented of examinations carried out on the transmission and scanning electron microscopes, as well as of the mechanical properties and tribological tests of the investigated coatings. Examinations of the chemical compositions of the deposited coatings were also carried out using the X-ray energy dispersive spectrograph EDS, glow-discharge optical emission spectroscope GDOS, and using the X-ray diffractometer. The inserts made from Si3N4 were multilayer coated in the PVD process with the TiN, TiN + multiTiAlSiN + TiN, TiN + TiAlSiN + TiN, and TiN + TiAlSiN + AlSiTiN coatings. Additional investigations were carried out to compare coatings obtained in this way on inserts from various manufacturers offering the nitride tool ceramics with the CVD coatings based on the Al2O3 and TiN layers. Basing on the metallographic examinations results it was found out that the multilayer PVD and CVD coatings were uniformly put down onto the substrate and the particular layers adhere closely to each other. It was found out in the microhardness tests of the coatings that the TiN + multiTiAlSiN + TiN one has the highest hardness. It was demonstrated also that all CVD coatings are characterised by very good adhesion to the substrate compared to the PVD coatings. Results of the X-ray qualitative phase analysis confirm occurrences of phases coming from coatings and the substrate. Analyses of the chemical composition – EDS and GDOS confirm presence of both titanium, aluminium, silicon, nitrogen, and oxygen in the investigated coatings and of silicon and nitrogen in the investigated substrate.

The aim of the present research of wear behaviour on the PVD-coated solid carbide end mills in dry high-speed cutting (HSC) is to find the main causes for unpredicted tool life. The contribution presents some results of characteristic wear types. The high cutting temperature, which is a result of high-speed cutting enhance diffusion and oxidation process. Diffusion processes between the chip and the top rake surface of the cutting edge result in crater wear, and oxidation reactions with the environment (air cooling in dry cutting) induce scaling of the cutting edge. The characteristic wear of such tools (so-called “central wear”) can be used to define the tool life in the case of high-speed milling of alloyed tool steel X63CrMoV5.1 (hardness >47 HRC).