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1

Influence of low melting point alloy on strength properties of epoxy resin

Stabik J., Wierzbicki Ł.

Archives of Materials Science and Engineering

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2013

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Vol. 60, nr 1

13--23

EN

Purpose: The aim of the work was to determine the effectiveness of the modification of the epoxy resin strength and elasticity by Wood’s alloy particles addition. Design/methodology/approach: Manufacture method of thermosetting polymer matrix composite materials reinforced with the Wood’s alloy particles was searched. First of all mixing conditions were differentiated to obtained good dispersion of reinforcement in polymeric matrix. Microscopic examination of samples cross-sections was performed in order to search the structure of prepared composite materials. The strength and elasticity of composites were investigated using compression test. Findings: The results of the compression tests and their analysis are presented. The paper also presents microscopic images of structure of prepared composites. Research limitations/implications: Presented research was limited to composites in the form of small samples. The developed technology of this type of composites preparation is limited to small volumes because of sedimentation process action. Practical implications: Materials with low melting point alloy content show many possible applications. First of all they are materials with higher thermal conductivity and electrical conductivity than standard polymeric materials. Conducted research programme showed that these materials exhibit also good mechanical properties. Originality/value: Preparation method of thermosetting polymer matrix composite materials reinforced with the Wood’s alloy particles fabricating method was developed. Composites with good mechanical properties were obtained. Microscopic examination of samples cross-sections in order to search the structure of prepared composite materials was performed. Composites with small particles evenly dispersed in epoxy matrix were achieved.

2

Disadvantages of applied lacquer coatings on polymer substrate

Wierzbicki Ł., Kulesza J.

Journal of Achievements in Materials and Manufacturing Engineering

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2012

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Vol. 55, nr 2

291--298

EN

Purpose: The use of polymer parts in automotive industry gives economic and practical savings. This is evoked by weight reduction of the used construction elements. However, polymer parts usually require application of coatings to ensure high quality surface. The painting of polymer materials is one of the most popular and well known methods. Assumptions of the study presented in this article were an attempt to create an atlas of lacquer coating disadvantages. Design/methodology/approach: Assumptions of this study were an attempt to identify lacquer coating disadvantages. Samples of the parts with disadvantages were prepared with the use of microtome and then viewed on an optical microscope. The defects have been described and the causes of their formation have been identified. Findings: The paper shows the examples of common disadvantages of polymer coatings’ application in automotive industry. Research limitations/implications: In automotive industry, they are often used as a substrate - metals or other materials. The description and identification of disadvantages of coatings on these substrates requires further study. Practical implications: The identification of disadvantages of the applied lacquer coatings on polymer substrate allows to eliminate them. Through the improvement and generation of new technologies of coating industry as a major supplier to the very large automotive industry, the industry will continue to thrive, grow and maintain its economical competitiveness in the global marketplace. Originality/value: Applications of multilayer polymer coatings in automotive industry are rarely described in literature - especially the application on polymers substrate. The description and identification for the emergence of the most frequent reasons of lacquer disadvantage is a novelty in this article.

3

Thermography in plastics welding processes assessment

Rojek M., Stabik J., Muzia G.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 41, nr 1-2

40-47

EN

Purpose: The purpose of this paper was to describe the possibilities of thermovision technique to evaluate temperature distribution on heating tools surfaces of plastics welding machines and temperature distribution on heated surfaces of welded parts. Design/methodology/approach: Heating tools of butt fusion, socket fusion and infrared fusion machines were tested using thewrmovision camera. Interrelation was shown between temperature distribution on heating tools and welded parts surfaces. Findings: The quality of ready welds is essentially dependent on uniform heating of welded parts. Achieved results shown that thermography may be applied as a tool to quick temperature distribution evaluation on heating elements and welded parts. Research limitations/implications: In order to evaluate temperature distribution with thermovision camera complete surface of heating element must be “visible”. The maximum angle between camera axis and line perpendicular do scanned surface is 30°. Practical implications: Achieved results showed that thermography may be applied in industrial practice to test heating elements of plastics welding machines. Also welded parts may be scanned with this methodology. Originality/value: The originality of the research comprises in evaluation of relation between temperature distribution on heating elements and temperature distribution on welded parts heated with given tools.

4

Structure of gas-assisted injection moulded parts

Stachowiak T., Jaruga T.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 38, nr 2

139-145

EN

Purpose: The purpose of this research was evaluation of the structure in the cross-section of gas-assisted injection moulded parts. The parts investigated were stroller handles made from polypropylene. Design/methodology/approach: Polymer structure was observed in the cross-section using the optical microscope. The microtomed slices cut from the manufactured parts were observed in polarized light. The parts obtained with different injection moulding temperature values were tested. Findings: was found that spherulites size differs in the cross section. A big gradient of spherulites is observed in the area near the skin while the spherulites contacting the gas channel are of similar size - like those in the part centre. Research limitations/implications: The investigation is limited to semi-crystalline polymers, like polypropylene. In case of amorphous polymers spherulitic structure does not occur. Practical implications: The investigation results can contribute to the improvement of the knowledge about gas-assisted injection moulding and can also be helpful in selection of proper injection moulding parameters, in order to obtain good polymer structure in the part. Originality/value: Gas-assisted injection moulding is a non-conventional manufacturing process. Investigation in this field is not so common like in conventional injection moulding that has much longer history.

5

Mechanical behaviour characterizing and simulation of polyacrylate rubber

Santos dos D., Batalha G. F.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 38, nr 1

33-40

EN

Purpose: of this paper is to investigate the influence of EB radiation on the mechanical behaviour of UV curing polyacrylate rubber (ACM) and to simulate its behaviour. Design/methodology/approach: The material was irradiated by two different EB doses, 100 kGy and 250 kGy, its mechanical behaviour was investigated with the help of uniaxial, equibiaxial and planar shear experiments. The results were applied to the Ogden’s Model (1972) in order to obtain the parameters to simulate the material behaviour by finite element method (FEM) and to compare experimental and FEM curves. The structure molecular changes caused by EB were investigated with the help of infrared spectroscopy. Findings: In most cases the experimental results showed an increase in the strength at rupture and a decrease in the elongation at the rupture with increasing of radiation dose. Equibiaxial and planar shear tests presented similar behaviour like uniaxial results, in terms of elongation decrease and strength increase, with some deviations. Ogden’s Model third order provided simulated curves with similar behaviour in comparison to experimental curves. The infrared spectroscopy showed different chemical group contents in the analyzed regions, surface and middle region. Research limitations/implications: Two doses of EB radiation were applied; higher or lower doses were not investigated. Practical implications: Improved behaviour of UV curing ACM can extend the range of industrial applications, or improve its performance in known applications. Originality/value: Usually EB radiation has been used to modify polymeric structure and to improve thermal and mechanical polymers behaviour. Regarding like rubber materials EB is usually applied as an alternative form of vulcanization. UV is a new type of curing for polyacrylate rubbers, which are usually cured by thermal processes.

6

Fractographic study of high-density polyethylene gas pipe following Small Scale Steady State test

Pusz A., Michalik K.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 38, nr 2

131-138

EN

Purpose: The present work attempts to examine the failure performance of high density polyethylene [HDPE] gas pipe through a fractographic study of the fracture morphology following Small Scale Steady State test (S4). Failure mechanisms are discussed based on the fracture morphologies resulting from these tests. There are many instances where the rapid propagation of cracks is the result of fluid pressure acting on piping structures. This problem is recognized as one of the most important issues of dynamic fracture mechanics. A fractographic study of the HDPE type of a gas pipe has been undertaken. Design/methodology/approach: Scanning electron microscopic (SEM) observations were used to identify elementary process involved in the crack initiation and propagation. Findings: Based on an investigation of the Small Scale Steady State (S4) test, in order to assess the fracture behaviour of polyethylene (PE) gas distribution pipe material during rapid crack propagation (RCP). Failure mechanisms are discussed based on the fracture morphologies resulting from these tests. The influence of molecular architecture on the rapid crack propagation (RCP) resistance of high-density polyethylene pipes was investigated. It was concluded that high molecular weight, high crystallinity and a relatively narrow molecular weight distribution are important architectural attributes for RCP resistance. Research limitations/implications: Applying S4 test is limited to thermoplastic materials. Practical implications: Presented method can be applied for other thermoplastic materials in the future. Originality/value: The expressed method can be applied in the future for developing the research on the process with rapid crack propagation of polymers.

7

Compositional, physical and chemical modification of polylactide

Żenkiewicz M., Rytlewski P., Malinowski R.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 43, nr 1

192-199

EN

The purpose of this article was to review some of the modification methods applied to improve mechanical, barrier and/or surface properties of polylactide (PLA). Design/methodology/approach: The presented modification methods were classified into three groups due to the dominant role of compositional, physical or chemical factor effecting the most PLA properties. Findings: It was found that incorporation of small amounts of montmorillonite up to 5% leads to formation of a nanocomposite with enhanced tensile strength and improved barrier properties. Corona treatment of pure PLA and PLA contained MMT nanofiller causes a significant decrease in the water contact angle and does not essentially affect the diiodomethane contact angle. This treatment leads to an increase in surface free energy that is much more significant for pure PLA than for PLA containing MMT nanofiller. It was also found that with increasing number up to 1000 of laser pulses of energies 5 mJ/cm2 an increase in surface free energy was observed, while the next laser pulses caused decrease of this energy. The determination and comparison of the influence of 3 wt.% of trimethylopropane trimethacylate (TMPTA) and 3 wt.% of trially isocyanurate (TAIC) crosslinking agents on the thermomechanical properties of electron beam irradiated PLA was reported. Research limitations/implications: A number of various modification methods are widely reported in literature. In this article a review of only such modification methods is presented, which are in line with the newest trends in polymer industry and science. Practical implications: There are a number of PLA properties, which need to be improved to satisfy specific application conditions. For that reasons researches are leading to find suitable modification methods to improve selected properties of PLA. Originality/value: This article presents some of modification methods, which are in line with the newest trends in polymer industry and science.

8

Application of FEM for solving various issues in material engineering

Dobrzański L. A., Pusz A., Nowak A. J., Górniak M.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 42, nr 1-2

134-141

EN

Purpose: The aim of this work is to present selected problems concerning the application of Finite Element Method in materials engineering on the example of chosen program which makes the most of this method to simulation. Design/methodology/approach: Application of Finite Element Method was discussed and essential advantages resulting from application of it are pointed. Findings: Description of the importance and the utility of FEM during solving of problems dealing with very complicated geometry complex state of loadings, various boundary conditions and/or various materials. Research limitations/implications: The method must be applied very carefully because its results do not refer to real system but only to the model one. The obtained results of FEM calculations can be used to solve many problems at the early step of designing with success. Originality/value: The application of FEM method during working out the internal prosthesis of oesophagus which will enable help people suffering from oesophageal cancer.

9

The elimination of micropores and surface defects in aramid-silicon laminated materials with special properties

Dobrzański L. A., Pusz A., Nowak A. J.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 35, nr 2

121-128

EN

Purpose: Development of the manufacturing technology of aramid-silicon laminated material and define of the micro-cavities amount during production of the laminates and identification of their influence on product properties with assumed medical implantation. Design/methodology/approach: Aramid-silicon laminated material was made by method of manual formation of laminates, that is impregnation of reinforcement with matrix, to hardening silicone process using hardening methods connected with hot. Created material was observed on Olimpus HIGLIGHT 2000 optical microscope with magnification 40x. Findings: The results show that the preliminary manufacturing technology of aramid-silicon laminated materials allows to create a material with specific and special properties. Aramid-silicone laminate could be used in medicine for example as gullet prosthesis. Research limitations/implications: Carried out investigations show the problem with cautioning and ageing which are very important in having proper percentage of intensifier in developed material. Originality/value: Taking into account the material specific properties one can suppose that the aramid-silicon laminated material would be useful in medicine. Aramid silicone laminate could be attractive alternative for composite material used in medical and others purposes.

10

The effect of micropores on output properties of laminate materials with assumed medical implantation

Dobrzański L. A., Pusz A., Nowak A. J.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 37, nr 2

408-415

EN

Purpose: Examination of elaborated composite material in terms of specific application in medicine – as internal prostheses of oesophagus. Development of the manufacturing technology of aramid-silicon laminated material and definition of the micro-cavities amount formed during production of the laminates. Design/methodology/approach: Aramid-silicon laminated material was made by a method of manual formation of laminates that is impregnation of reinforcement with matrix to hardening silicone process using hardening methods connected with heat. Created material was observed on Axiovert 450M light-microscope of Option Company at 100 x magnification. Findings: The results show that the preliminary manufacturing technology of aramid-silicon laminated materials allows creating a material with specific and special properties. Aramid-silicone laminate could be used in medicine for example as oesophagus prosthesis. Research limitations/implications: Carried out investigations show the problem with cautioning and ageing which are very important in having proper percentage of intensifier in developed material. Originality/value: Taking the material specific properties into account it seems that the aramid-silicon laminated material would be useful in medicine. Aramid silicone laminate could be attractive alternatively for composite material used for medical purposes and the others.

11

Swagelining as a method of trenchless piplines rehabilitation

Wróbel G., Pusz A., Szymiczek M., Michalik K.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 33, nr 1

27-34

EN

Purpose: The present study outlines the advantages of using trenchless methods for the rehabilitation of pipelines made of steel, concrete, cast iron etc. The authors describe causes of carrier pipe ageing and methods of their inspection and renovation. The technical aspects of choosing the renovation methods are also presented. The paper includes a decision-making flowchart for choosing the carrier pipes renovations. Design/methodology/approach: The 1980’s and 1990’s saw an explosion of new pipe installation and repair techniques which minimize the need to dig continuous trenches to bury the pipeline, so called ‘trenchless technologies’. The trenchless technologies have been widely applied for the rehabilitation of various pipelines such as sewage systems, gas pipelines or water supply systems. There has been characterized the swagelining technology which is based on one of the metal working technologies and namely the sinking of pipes. Findings: The PE pipe stress in the drawing die zone has been analyzed and an attempt has been made to analyze the mechanisms causing the elastic recovery of PE pipes. There have also been presented the diameter changes as the parameter of the elastic recovery which is a result of our own research conducted in accordance with the program developed. Research limitations/implications: Each pipeline renovation method has its advantages and disadvantages, possibilities and limitations, depending on the application. Practical implications: The work is an example of analysis of chosen trenchless renovation on the example of swageling technology. Originality/value: The trenchless renovation of pipelines certainly will be more readily used in the future because of wearing out of pipelines. The other reason is the lack of space for new utilities, increasing costs and road-surface restoration requirements.

12

Studying of kinetic growth of organic thin films

Weszka J. P., Jarka P., Pakuła D., Dobrzański L. A., Domański M., Jurusik J.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 35, nr 1

29-36

EN

Purpose: of this paper: Studying of growth kinetic of organic thin film prepared by vacuum thermal evaporation technology. Design/methodology/approach: Applying of quartz crystal microbalance to thickness control of organic thin films deposition process. Findings: Results of this issue suggesting that the kinetics of organic thin films is depending of current flowing through the crucible (crucible temperature). Research limitations/implications: Kinetics of vacuum evaporation of thin film is different from that of inorganic thin films during the growth process. Practical implications: The means of connect the quartz crystal microbalance MSV 1843/AB with vacuum chamber, function and means of thickness and deposition rate measuring has been described. This scientific paper include also description of researching results of kinetics of organic and metallic thin film evaporation process by MSV 1843/AB quartz crystal microbalance and verification these results by comparing them with results from other measuring techniques. Originality/value: Controlling thickness of thermally evaporated organic thin film during the film growth process.

13

Some effects of multiple injection moulding on selected properties of ABS

Żenkiewicz M., Rytlewski P., Moraczewski K., Stepczyńska M., Karasiewicz T., Malinowski R., Ostrowicki W.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 37, nr 2

361-368

EN

Purpose: The purpose of this work was to investigate the influence of multiple (up to 10 times) injection moulding of acrylonitrile butadiene styrene (ABS) on some properties of the obtained moulded pieces. Design/methodology/approach: The investigated samples were obtained during the industrial injection moulding. There were determined the sample mechanical properties (by a tensile test), melt flow rate, temperatures of phase transitions (by differential scanning calorimetry, DSC), temperatures of thermal degradation (by thermogravimetric analysis, TGA), as well as storage modulus and damping coefficient (both by dynamic mechanical analysis, DMA). Findings: After the first injection mouldings, minor decreases (ca. 2.0 %) in the tensile strength were observed. After the next injection mouldings, this quantity did not change much. The melt flow rate increased along with the number of injection mouldings. The glass transition temperatures (from DSC) of butadiene and acrylonitrile styrene fractions don’t vary with the number of injection mouldings and are ca. 61 and +104şC, respectively. Research limitations/implications: In order to confirm that degradation process occurs in ABS during injection mouldings, further investigation is necessary, mostly that on variations in the mean molecular weight of ABS. Practical implications: The studies carried out by now indicate that there are no arguments not to subject the ABS technological waste to the management by material recycling. Originality/value: It has been observed that the largest changes in the tensile strength and melt flow rate of ABS occur during its first injection moulding and a melt flow rate increases slightly with the number of injection mouldings. The temperatures of phase transitions and thermal as well as the storage modulus and damping coefficient of ABS do not essentially change after repeated injection mouldings.

14

Effects of temperature and plasma treatment on mechanical properties of ceramic fibres

Xiem N. T., Kroisová D., Louda P., Hung T. D., Rozek Z.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 37, nr 2

526-531

EN

Purpose: The aim of this study is an investigation and comparison of mechanical properties of ceramic fibres after they were influenced by temperature and plasma treatment. Design/methodology/approach: Single filament after being processed at different temperatures (200oC, 400oC, 700oC and 1000oC) and methane plasma treatment was separated with a magnifier, prepared on a punched mounting tab, and was evaluated in accordance with Japanese Industrial Standard. Findings: Preliminary results of the improvement in tensile strength, Young’s modulus, elongation of ceramic fibres after plasma treatment are studied in this paper. Research limitations/implications: The samples were tested for optimized parameters of plasma modification and optimized parameters of plasma to ceramic fibres curing. There was not enough time to test the adhesion between Geopolymer matrices and ceramic fibres. Practical implications: In the future, our work will be focused on optimization of parameters for plasma modification of fibres made of different materials and applying this method to improve the fibre and Geopolymer matrix adhesion. Originality/value: The value of this work is defined by the influence of plasma treatment parameters on quality, mechanical properties of ceramic fibres and increasing the adhesion between matrices and reinforcements.

15

Physical properties of polyazomethine thin films doped with iodine

Hajduk B., Weszka J., Jarząbek B., Jurusik J., Domański M.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 24, nr 2

67-70

EN

Purpose: The aim of this paper is to show influence of doping 1,4-phenylene-methylenenitrilo-1,4- phenylenenitrilomethylene (PPI) with iodine and to propose doping mechanism and its impact on electronic structure of doped PPI thin films. Design/methodology/approach: Influence of iodine doping on electronic structure of polyazomethine thin films was investigated. Optical absorption spectra, XRD spectra and AFM images of doped PPI thin films were recorded. Findings: Doping mechanism relys on removing one electron from PPI pi-system by 12 molecules and forming counterions 13-. Formation of positive polaron means that doping of polyazomethine PPI is p - type. Research limitations/implications: Influence of iodine doping on electrical properties (with increasing of temperature) of PPI thin layers will be checking with Kethley appliance. We plan these measurements to be done in the foreseeable future. Practical implications: Iodine doping of thin PPI films process could results in better electrical conductivity of PPI, so doped polyazomethine films could find some applications for photonic and optoelectronic devices. Originality/value: Conjugated PPI is rarely enough reported but it is very interesting material as it has nitrogen atom in the backbone and it is isoelectronic counterpart of polyparaphenylenevinylene (PPV). This paper show that doping influences on surface morphology, cristallinity and optical properties of polymer. Furthermore, doping mechanism and changes of polymer electronic structure have been proposed in this paper.