Wyniki wyszukiwania - Biblioteka Nauki

1

Informative technologies in the material products designing

100%

Dobrzański L. , Honysz R.

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2012

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tom Vol. 55, nr 1

37-44

EN

Purpose: The purpose of materials products designing is to optimize their functional properties in terms of technological, economic and ecological aspects. Design/methodology/approach: Materials science is an example of a field, in which informative technologies used to understand and anticipate the construction of materials and their properties has a significant success. Findings: Innovation and development of new informative technologies and the widespread use of modern materials will be essential for promoting economic development in the near future by application of entirely new, interdisciplinary field of science: computational materials science. Practical implications: The use of informative technologies allows exploring in a short time and at low expense, many solutions for the design of the mechanical properties of materials and their simulation beyond the standardized range. Originality/value: The most important benefit of material designing is the ability of suitable selection of material (or its manufacturing) for various applications with use of informative technologies.

2

The numerical analysis of Hi-temp 095 wire drawing process

86%

Wiewiórowska S. , Muskalski M. , Suliga M. , Pełka M.

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2008

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tom Vol. 27, nr 2

175-178

EN

Purpose: The aim of this paper was the optimization of wire drawing process parameters. Design/methodology/approach: The hard binding material determined according to American standard ANSI/AWSA 5.8-92 as High-temp 095 was chosen to the analysis of wire drawing process. It is hard solder with high fluidity properties. Findings: Wires, bars and strips are the most often use forms of this solder on the base of copper with low deformability properties, which shows crack sensitivity during cold plastic working processes so there was the necessity to determining optimal parameters of initial material use to the later cold plastic working processes. Research limitations/implications: To the numerical analysis of Hi-temp 095 wire drawing process the Drawing 2d programme based of finite element method, has been use, for initial materials obtained on the casting and extrusion way. Practical implications: The optimal properties of basic material use for further plastic working processes were determined. Originality/value: The rheology of materials after casting and extrusion processes were determined.

3

Project of neural network for steel grade selection with the assumed CCT diagram

86%

Dobrzański L. , Malara S. , Trzaska J.

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2008

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tom Vol. 27, nr 2

155-158

EN

Purpose: The aim of this paper was developing a project of neural network for selection of steel grade with the specified CCT diagram - structure and of harness after heat treatment. Design/methodology/approach: The goal has been achieved in the following stages: at the first stage characteristic points of CCT diagram have been determined. At the second stage neural network has been developed and optimized. Findings: The neural network was developed in this paper, that allowed selection of steel grade with the assumed CCT diagram. Research limitations/implications: Created method for designing chemical compositions is limited by the established ranges of mass concentrations of elements. The methodology demonstrated in the paper makes it possible to add new steel grades to the system. Practical implications: The method worked out may be used in computer steel selection systems for the machine parts put to heat treatment. Originality/value: Presented computer aided method makes use of neural networks, and may be used for selecting the steel with the required structure after heat treatment.

4

Computational investigation of the tensile behaviour of the hard coated Ti-6Al-4V alloy

86%

Ziaja W.

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2008

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tom Vol. 26, nr 2

175-178

EN

Purpose: Modification of the surface layer of the titanium alloys is frequently applied in order to improve their tribological properties. Various surface engineering techniques can be used to produce hard coatings, e. g. composed of metallic carbides, nitrides or more recently DLC. The coating and substrate materials possess significantly different stiffness and strength properties. This can lead to premature failure of the usually elastic coating in case of plastic deformation of the substrate when the high stresses are encountered. Cracking of the hard coating leads to stress concentration and localized plastic deformation of the substrate that can modify macroscopic deformation behaviour of the system. In the paper the influence of coating and substrate properties on local plastic deformation of substrate material was numerically investigated. Design/methodology/approach: Two dimensional finite element analysis of the process of tensile deformation of titanium alloy with hard elastic coating was carried out. Two cases were analyzed, i. e. with and without diffusion strengthened layer underlying the coating. Findings: The influence of the difference in Young's modulus between coating and substrate material, yield strength of substrate material, coating thickness and depth of the crack in the coating on local plastic deformation of substrate material was determined. Research limitations/implications: Some extension of the numerical model should be pursued in order to take into account initiation of microcracks in surface layer of the coated material and process of coating delamination. Practical implications: The results could be used in the element design process for selection of parameters of surface layer with complex structure for load bearing applications. Originality/value: The mechanical behaviour of hard coated material was most frequently studied for indentation and friction conditions and much less investigations were carried out for coated systems under tension or compression.

5

Application of artificial neural networks in modelling of quenched and tempered structural steels mechanical properties

72%

Dobrzański L. A. , Honysz R.

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2010

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tom Vol. 40, nr 1

50-57

EN

Purpose: This paper presents the application of artificial neural networks for mechanical properties prediction of structuralal steels after quenching and tempering processes. Design/methodology/approach: On the basis of input parameters, which are chemical composition, parameters of mechanical and heat treatment and dimensions of elements, steels’ mechanical properties : yield stress, tensile strength stress, elongation, area reduction, impact strength and hardness are predicted. Findings: Results obtained in the given ranges of input parameters indicates on very good ability of artificial neural networks to values prediction of described mechanical properties for steels after quenching and tempering processes. The uniform distribution of descriptive vectors in all, training, validation and testing sets, indicates on good ability of the networks to results generalisation. Practical implications: Artificial neural networks, created during modelling, allows easy prediction of steels properties and allows the better selection of both chemical composition and the processing parameters of investigated materials. It’s possible to obtain steels, which are qualitatively better, cheaper and more optimised under customers needs. Originality/value: The prediction possibility of the material mechanical properties is valuable for manufacturers and constructors. It allows the preservation of customers quality requirements and brings also measurable financial advantages

6

Computer models of steam pipeline components in the evaluation of their local strength

72%

Okrajni J. , Essler W.

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2010

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tom Vol. 39, nr 1

71-78

EN

Purpose: The paper discusses the issue of modelling the heating and cooling processes of T-pipes in a power plant pipeline in the start-up conditions of a boiler. The main purpose of this work is the description of the mechanical behaviour of power plant components working under mechanical and thermal loading and validation of the computer modelling methods. Design/methodology/approach: The FEM modelling has been used to describe the local stress-strain behaviour of the chosen component. Findings: The reasons for the presence of high and variable in time temperature gradients in the components of the main steam pipeline include, among other things, variable values of the coefficient of heat transfer between the pipeline material and the medium flowing inside it, which, at this stage of boiler operation, may change its state. Unsteady operation of a pipeline, especially in case of subsequent boiler start-ups, may induce thermal stresses which exceed the values of allowable stress in components of complex shapes. Research limitations/implications: The possibility of applying the durability criteria currently assumed in standards still requires justification and confirmation in laboratory and industrial conditions to be closer to the real components behaviour. In such situation the presented analysis is the part of the complex investigation method which main purpose is increasing accuracy of the TMF process description and thermo-mechanical life assessment. Practical implications: The calculations carried out may constitute a basis for developing a material test parameters which would bring closer the fatigue conditions appearing locally in the analysed components. The method of stress-strain behaviour analysis used in the paper could be useful in the practical cases when the real components mechanical behaviour would be analysed. Originality/value: The main value of this paper is the own method of the mechanical behaviour analysis of the power plant component. This method includes the temperature fields analysis taking into account the boundary conditions based on the operation parameter data and the thermoplastic material model. The material stress-strain behaviour has been treated as the local phenomenon, that could be modelled by FEM.

7

Methodology of high-speed steels design using the artificial intelligence tools

72%

Sitek W.

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2010

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tom Vol. 39, nr 2

115-160

EN

Purpose: The main goal of the research carried out was developing the design methodology for the new high-speed steels with the required properties, including hardness and fracture toughness, as the main properties guaranteeing the high durability and quality of tools made from them. It was decided that hardness and fracture toughness KIc are the criteria used during the high-speed steels design. Design/methodology/approach: In case of hardness, the statistical and neural network models were developed making computation possible of the high-speed steel hardness based solely on the steel chemical composition and its heat treatment parameters, i.e., austenitizing- and tempering temperatures. In this case results of own work on the effect of alloy elements on the secondary hardness effect were used, as well as data contained in catalogues and pertinent standards regarding the high-speed steels. In the second case - high-speed steels fracture toughness, the neural network model was developed, making it possible to compute the KIc factor based on the steel chemical composition and its heat treatment parameters. The developed material models were used for designing the chemical compositions if the new high-speed steel, demonstrating the desired properties, i.e., hardness and fracture toughness. Methodology was developed to this end, employing the evolutionary algorithms, multicriteria optimisation of the high-speed steels chemical composition. Findings: Results of the research carried out confirmed the assumption that using the data from catalogues and from standards is possible, which - would supplement the set of data indispensable to develop the assumed model - improving in this way its adequacy and versatility. Practical implications: Solutions presented in the work, based on using the adequate material models may feature an interesting alternative in designing of the new materials with the required properties. The practical aspect has to be noted, resulting form the developed models, which may successfully replace the above mentioned technological investigations, consisting in one time selection of the chemical composition and heat treatment parameters and experimental verification of the newly developed materials to check of its properties meet the requirements. Originality/value: The presented approach to new materials design, being the new materials design philosophy, assumes the maximum possible limitation of carrying out the indispensable experiments, to take advantage of the existing experimental knowledge resources in the form of databases and most effective computer science tools, including neural networks and evolutionary algorithms. It should be indicated that the materials science knowledge, pertaining oftentimes to the multi-aspect classic problems and described, or - rather - saved in the existing, broadly speaking, databases, features the invaluable source of information which may be used for discovery of the unknown so far relationships describing the material structure - properties relations.

8

Prediction of mechanical properties of hot rolled steel products

72%

Simecek P. , Hajduk D.

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2007

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tom Vol. 20, nr 1-2

395-398

EN

Purpose: Model for prediction of mechanical properties of rolled steel products after final cooling from exit rolling temperature is one of the basis component of any software for complex computer simulation of rolling technologies. Theoretical background and implementation of such software tool is described. Design/methodology/approach: After calculation of cooling curves by any technology dependent Shell the software tool MECHP can be called to predict CCT Diagram from current chemical composition of steel and initial properties of deformes austenite first than structure shares (percentage of ferrite, pearlite, bainite and martensite) resulting from austenite decomposition process for given cooling curve and finally mechanical properties of final product after cooling (hardness, yield stress, tensile strength) are calculated. Implementation of MECHP tool into the software RollFEM3D Finite Elements Method simulation of rolling processes is presented. Findings: comparison of MECHP calculations with measured process data (water cooling and subsequent air cooling of hot rolled narrow plate and wire) shows correspondence that is satisfactory for using in control of process cooling technology. Practical imlications: Results of verification showed that the software tool MECHP is implementable as a postprocessor into off-line rolling process simulation software or can be used as a mechanical properties predictor in software for on-line control of cooling. Originality/value: Developing of technology independent Library solving the problem of final mechanical properties prediction for various kinds of rolling technologies.

9

Fractal and multifractal characteristics of CVD coatings deposited onto the nitride tool ceramics

72%

Kwaśny W. , Pakuła D. , Woźniak M. , Dobrzański L. A.

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2007

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tom Vol. 20, nr 1-2

371-374

EN

Purpose: The goal of this work is the fractal and multifractal characteristics of the TiN+Al2O3 and Al2O3+TiN coatings obtained in the CVD process on the Si3N4 tool ceramics substrate. Design/methodology/approach: The investigations were carried out of the multi-edge inserts from the Si3N4 nitride tool ceramics uncoated and coated with the TiN+Al2O3 and Al2O3+TiN coatings deposited in the CVD process. Determining the fractal dimension and the multifractal analysis of the examined coatings were made basing on measurements obtained from the AFM microscope, using the projective covering method. Findings: Investigations carried out confirm that the fractal dimension and parameters describing the multifractal spectrum shape may be used for characterizing and comparing surfaces of coatings obtained in the CVD processes and of the substrate material from the Si3N4 nitride tool ceramics. Research limitations/implications: Investigation or relationship between parameters describing the multifractal spectrum and physical properties of the examined materials calls for further analyses. Originality/value: Employment of multifractal geometry in materials engineering provides the opportunity to work out more complete, also quantitative, characteristics of properties of the investigated objects. Multifractal analysis makes it possible to characterise in the quantitative way the extent of irregularities of the analysed surface.

10

Stereometry specification of anodised and PVD coated surface of aluminium alloy

72%

Konieczny J. , Labisz K. , Wieczorek J. , Dobrzański L.

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2009

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tom Vol. 38, nr 2

85-92

EN

Purpose: The aim of the work is to present the influence of casting method and anodic treatment parameters on properties, thickness and structure of an anodic layer with (PVD) physical vapour deposition method achieved TiN layer formed on aluminum casting alloys. Design/methodology/approach: Investigations were carried out on the laser profile measurement gauge MicroProf from company FRT, abrasive wear test was made with using ABR-8251 equipment delivered by TCD Teknologi ApS and microstructure investigations were made with using a light microscope equipped with an electronic camera configured with a computer on two casting aluminum alloys which both were founding by pressure die casting and gravity casting. Findings: The researches included analyze of the influence of geometry, roughness and abrasive wear resistant of anodic layer obtained on aluminum casts. The studied PVD coating deposited by cathodic arc evaporation method demonstrates high hardness, adhesion and wear resistance. Research limitations/implications: Contributes to research on anodic and PVD layer for aluminum casting alloys. Practical implications: Conducted investigations lay out the areas of later researches, especially in the direction of the possible, next optimization anodization process of aluminum casting alloys, e.g. in the range of raising resistance on corrosion. Originality/value: The range of possible applications increases staidly for example for materials used on working building constructions, elements in electronics and construction parts in air and motorization industry in the aggressive environment.

11

Materials science virtual laboratory as an example of the computer aid in materials engineering

72%

Dobrzański L. A. , Honysz R.

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2007

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tom Vol. 24, nr 2

219-222

EN

Purpose: The purpose of the presented article is to describe the material science virtual laboratory, which is an open scientific, investigative, simulating and didactic medium for the realization of the didactic and educational tasks performed by traditional and e-learning methods. Design/methodology/approach: The laboratory is an aggregate of testers and training simulators, placed in the virtual reality and created in various languages and the programming techniques, which represents the properties, functionality and manual principles of real equipment installed and accessible in the real laboratories of scientific universities. Findings: Application of the equipment, that is practically imperishable, cheap in exploitation and easy in the use certainty will encourage students and scientific workers to independent audits and experiments in situations, where the possibilities of their execution in the true investigative laboratory will be limited because of the high material costs, difficult access to real equipment or the possible risk of his damage. Practical implications: The use possibilities of the virtual laboratory are practically unrestricted; it can be a base for any studies, course or training programme. It is assumed, that the project of the laboratory as fully multimedial. The participants of this laboratory can e.g. investigate training experiments from the definite field of material engineering, give questions, pass tests, contact with lecturers and the different users of the laboratory and obviously on participate in his design and content. Originality/value: The project of the virtual laboratory corresponds with the global tendency for expand the investigative and academical centers about the possibilities of training and experiments performance with use of the virtual reality. This enriches the education programme of the new abilities reserved so far exclusively for effecting only on real equipment.

12

Development of the virtual light microscope for a material science virtual laboratory

72%

Dobrzański L. A. , Honysz R.

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2007

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tom Vol. 20, nr 1-2

571-574

EN

Purpose: Article describe an idea, bases and construction procedures of Material Science Virtual Laboratory. Design/methodology/approach: As an example of virtual laboratory post a virtual light microscope used in metallographic investigations is presented. It allows to study the microstructures from different materials and alloys without use of real microscope placed in real laboratory. The only necessary equipment is the computer with internet connection. Findings: Continuous progress in computer technology and observed growth of computational power opens for material engineers new ground of computer scientific activities with use of virtual reality and computer technologies. Research limitations/implications: The virtual laboratory, even the best programmed, will never be better than the modest real laboratory, but it is good for training and as introduction to further investigations on a real equipment in real laboratory. Practical implications: Virtual reality can be efficiently applied to processes of education, increasing of qualifications and for basics, predefined experiments. Originality/value: In spite of considerable creation difficulties, virtual laboratory is a future solution for environments with limited apparatus supplies.

13

The multi-scale FEM simulation of the drawing processes of high carbon steel

72%

Milenin A. , Muskalski Z. , Wiewiórowska S. , Kustra P.

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2007

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tom Vol. 23, nr 2

71-74

EN

Purpose: The influence of cementite lamellas orientation on mechanical and technological properties of wire experimentally show up during investigation of drawing processes with change the direction of drawing between passes. The purpose of this paper is to develop a mathematical model of cementite and ferrite deformation during drawing processes and receive an information about transformation of a pearlitic structure of wire during drawing. Design/methodology/approach: The wire drawing processes was investigated in two levels - using the 2-dimensional rigid-plastic finite element method (macro-level) and modelling of a microstructure change (micro-level). In micro-level the process of deformation of representative volume element (RVE) is considered. The pearlitic colony deformation and stress-strain state in RVE is modelled with help of the FEM. Research limitations/implications: The influence of initial cementite lamellas orientation on triaxity factor and localization of deformation in micro-level is investigated. The numerical simulation is shown a maximal non-uniform deformation of pearlite phases for the canting positions of the cementite lamellas relative the drawing direction. Practical implications: The results of article will be helpful for a fundamental understanding of pearlitic deformation during development of high strength steel wires for tire cord applications. Originality/value: A new model of two-phase grain deformation for wire drawing is proposed. The new conception of simulation of the boundary conditions for the RVE is based on the penalty method and uses a solution of the problem on macro-level.

14

Computer software for modelling CCT diagrams

72%

Jagiełło A. , Trzaska J. , Dobrzański L.

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2008

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tom R. 105, z. 3-M

87-94

EN

The purpose of the paper is to present a computer program for calculating Continuous Cooling Transformation diagrams for constructional and engineering steels. The computer program uses artificial neural networks for prediction of steel parameters after heat treatment. Input data are chemical composition and austenitising temperature. The results of calculation consist of temperature of the beginning and end of transformation in the cooling rate function, the volume fraction of structural components and hardness of steel cooled from austenitising temperature at a fixed rate. The algorithm can be used in designing new chemical compositions of steels with required hardness after heat treatment.

PL

Celem niniejszego artykułu jest prezentacja komputerowego programu do obliczania diagramów CTPc dla stali konstrukcyjnych. Program ten korzysta ze sztucznych sieci neuronowych do predykcji parametrów stali po obróbce cieplnej. Danymi wejściowymi są skład chemiczny oraz temperatura austenityzowania. Wynikami obliczeń są temperatury początków i końców przemian w funkcji szybkości chłodzenia, udziały procentowe faz oraz twardość stali po chłodzeniu z temperatury austenityzowania. Algorytm może być użyty w projektowaniu nowych stali z wymaganą twardością po obróbce cieplnej.

15

Application of artificial neural networks in modelling of normalised structural steels mechanical properties

72%

Dobrzański L. A. , Honysz R.

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2009

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tom Vol. 32, nr 1

37-45

EN

Purpose: This paper presents the application of artificial neural networks for mechanical properties prediction of structural steels after heat treatment. Design/methodology/approach: On the basis of such input parameteres, which are the chemical composition, the kind of mechanical and heat treatment and dimensions of elements, mechanical properties, such as strength, impact resistance or hardness are predicted. Findings: Results obtained in the given ranges of input parameters show very good ability of constructed neural networks to predict described mechanical properties for steels after heat treatment. The uniform distribution of descriptive vectors in all, training, validation and testing sets, indicate about the good ability of the networks to results generalisation. Practical implications: Created tool makes possible the easy modelling of described properties and allows the better selection of both chemical composition and the processing parameters of investigated materials. At the same time the obtainment of steels, which are qualitatively better, cheaper and more optimised under customers needs is made possible. Originality/value: The prediction possibility of the material mechanical properties is valuable for manufacturers and constructors. It allows preserving the customers quality requirements and brings also measurable financial advantages.

16

Crack initiation and propagation in FeAl matrix

72%

Renowicz D. , Skrzypek S. J.

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2007

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tom Vol. 22, nr 1

37-40

EN

Purpose: of this paper is evaluation of macroscopic and microscopic residual stresses and their influence on nucleation and development of cracking in Fe-Al-C cast alloy. Design/methodology/approach: In the case of particular chemical composition of Fe-Al-C alloy phenomena of its self-disintegration appears. Fracture mechanic methods with additional consideration of residual stresses were applied. The last one was measured by X-ray diffraction method. Findings: Measurements and calculations proved that crack nucleation and development is controlled by diffusion of hydrogen and oxygen to chemical reaction with Al4C3 precipitations. This process is enhanced by existing residual stresses. When total stress approaches to critical stress level the cracks gradually develops. Research limitations/implications: Microstructure of high-aluminium alloy (35.5 wt. % Al) consisted of brittle matrix with Al4C3 precipitations. Microstructure of this matrix appeared in a form of intermetallic compound as a superlattice FeAl. Practical implications: These kind of intermetallics is practically applied in high temperature working machine components. In many cases they are under high level of residual stresses. Any progress in describing of cracking in this type of microstructure has real practical importance. Modeling of crack nucleation and farther its growth using finite elements method confirmed with real measurements make an interesting approach in characterization of cracking of the alloys. Originality/value: Morphology of Al4C3 precipitation in FeAl superstructure alloy and its self-disintegration process can be ruled by chemical composition and solidification conditions. The elaborated physical model of cracking can be used to estimate durability of this Fe-Al-C alloy.

17

Employment of rough data for modelling of materials properties

72%

Sitek W.

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2007

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tom Vol. 21, nr 2

65-68

EN

Purpose: The paper presents the method of high - speed steels' secondary hardness modeling, basing on chemical composition and heat-treatment parameters. Design/methodology/approach: The computer modeling using statistical regression method were carried out basing on results of investigations of newly developed high - speed steels and rough data included in standards containing information about these steels. Findings: The models developed in the work was experimentally verified. The verification procedure consists of the evaluation of the conformity of the computational results with the experimental data. The obtained results indicate good conformity of calculations with experimental results since the error of calculations is c.a. 0.8 HRC. Research limitations/implications: The results presented are valid in the ranges of mass concentrations of alloying elements occuring in analyzed steels group and presented in the paper. Practical implications: The worked out model may be used in computer systems of steels' designing for cutting tools. Originality/value: The use of rough data for modeling of materials properties.

18

Analysis of stress state in DMTA and photoelasticity examinations

72%

Gnatowski A. , Palutkiewicz P. , Lubczyńska K.

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2010

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tom Vol. 46, nr 1

39-46

EN

Purpose: Determination of stresses at the change of Young modulus values in temperature function for polystyrene samples, by DMTA and photoelasticity method, was the aim of work. The numerical simulations of stress, strain and displacement in PS samples was presented. The numerical simulations of injection moulding process (using Moldflow Plastic Insight 5.0 software), include effects after injection process were conducted. Design/methodology/approach: Investigations were carried out for samples subjected to the one-axial bending. The computer simulations of changes of the stress and strain distribution within the range of elastic strains phase were done. The change in the value of the dynamic Young modulus and the mechanical loss tangent in function of temperature and oscillation frequency by the DMTA method was determined. To verify numerical simulation the photoelasticity research was done. Findings: Examinations made possible the determination of dynamic mechanical properties of polystyrene and changes in the stress distribution during the dynamic loading of the sample in function of temperature. Higher values of the Young modulus were observed within the range of elasticity. The stress increased with the increase in Young modulus, at the strain generated from push rot oscillation Research limitations/implications: The injection moulded part have large internal stresses, with higher value than stresses made from oscillation pushrot. The accuracy of used approximate method for computer simulations was not sufficient to indicate the Bielajew point. Practical implications: Investigated polymer is characterized by viscoelastic properties, so all indicators of the physical and chemical properties depend on not only the time but and also the temperature. Originality/value: To characterize properties of investigated polymer and to estimate the polymer usage in particular conditions, dependences of the storage module and the mechanical losses tangent was determined in function of temperature at the one-axial bending. The impact of internal stresses in the sample was investigate.

19

Thermo-mechanical fatigue conditions of power plant components

72%

Okrajni J.

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2009

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tom Vol. 33, nr 1

53-61

EN

Purpose: The main purpose of this work is the description of the mechanical behaviour of power plant components working under mechanical and thermal loading that cause the thermo-mechanical fatigue fracture in selected areas of the component surfaces. Design/methodology/approach: The computer modelling has been used to describe the local stress-strain behaviour of the chosen component. Findings: The values of variable in time temperature strains and stresses in selected points of the power plant header were determined. The points were located at the edges of holes through which water steam is supplied and carried away, where under use conditions the presence of cracks can be observed. That stresses and mechanical strains caused by the influence of a non-uniform temperature field may be significantly higher in comparison with the stresses and strains caused by the pressure inside the analysed component. Tensile thermal stresses of high values are created especially under conditions of sudden cooling during unsteady work of a power unit. Research limitations/implications: The possibility of applying the durability criteria currently assumed in standards still requires justification and confirmation in laboratory and industrial conditions to be closer to the real components behaviour. In such situation the presented analysis is the part of the complex investigation method which main purpose is increasing accuracy of the TMF process description and thermo-mechanical life assessment. Practical implications: The calculations carried out may constitute a basis for developing a material test parameters which would bring closer the fatigue conditions appearing locally in the analysed components. The method of stress-strain behaviour analysis used in the paper could be useful in the practical cases when the real components mechanical behaviour would be analysed. Originality/value: The main value of this paper is the own method of the mechanical behaviour analysis of the power plant component. This method includes the temperature fields analysis taking into account the boundary conditions based on the operation parameter data and the thermoplastic material model. The material stress-strain behaviour has been treated as the local phenomenon, that could be modelled by FEM.

20

Computer modelling system of the chemical composition and treatment parameters influence on mechanical properties of structural steels

72%

Dobrzański L. A. , Honysz R.

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2009

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tom Vol. 35, nr 2

138-145

EN

Purpose: This paper presents Neuro-Lab. It is an authorship programme, which use algorithms of artificial intelligence for structural steels mechanical properties estimation. Design/methodology/approach: On the basis of chemical composition, parameters of heat and mechanical treatment and elements of geometrical shape and size this programme has the ability to calculate the mechanical properties of examined steel and introduce them as raw numeric data or in graphic as influence charts. Possible is also to examine the dependence among the selected steel property and chosen input parameters, which describes this property. Findings: There is no necessity of carrying out any additional material tests. The results correlations between calculated and measured values are very good and achieve even the level of 98%. Practical implications: Presented programme can be an effective replace of the real experimental methods of properties determination in laboratory examinations. It can be applied as the enlargement of experimental work. Possible is also the investigation of models coming from new steel species, that wasn’t produced yet. Originality/value: The ability of the mechanical properties estimation of the ready, or foreseen to the use, material is unusually valuable for manufacturers and constructors. This signifies the fulfilment of customer’s quality requirements as well as measurable financial advantages for material manufacturers.