bluuebunny/crossref_metadata_2025 huggingface dataset:
Computer Aided Instrument to be Used as an Automatic Design Component
Authors: Oanta Emil , Panait Cornel , Lazaroiu Gheorghe , Dascalescu Anca Elena
Published: October 2014

The paper presents an original method to enhance the productivity of the design activity based on a dimensioning stage which integrates information from various sources: tabular data, diagrams, experimental data and others. The integration of such data in an analytic way is based on an original data processor which interpolates data and outputs diagrams, and outputs information regarding the laws of variation expressed as comma separated values data files, as well as automatically generated source code libraries in C++, Java and MATHLAB/GNU Octave. This automatically generated code is optimized in terms of execution time and it was verified in several applications. The data processor allows the user to visually verify the output data accuracy. The paper also presents some of the applications of the data processor: automatic design, method to enhance the accuracy of computer based calculus for both analytic and numerical methods, conversion of the discontinuous experimental data into laws of variation and experimental data processing in applied elasticity. There are several directions of future research, such as: a more general mathematical approach, development of a more general computer based instrument with increased flexibility and accuracy. Also, a complex software for applied elasticity calculi based on the results of the data processor is under development. Implementation of these applications in commercial CAD/CAE applications is another direction of research.
Integrated Approach to the Designing Process of Complex Technical Systems
Authors: Gwiazda Aleksander , Sękala Agnieszka , Monica Zbigniew , Banaś Wacław
Published: October 2014

The paper presents the specific approach to the designing process. This approach bases on the concept of integrated designing taking into consideration the three main attributes and three main subsystems of each technical mean. The attributes describing the features of an optimal technical mean include: the geometric form (including the mutual relations), the material form (including macroscopic and microscopic structure) and the assembly form (so called the dynamic form representing the constructional features obtaining only in the assembly process). The three specified constructional subsystems are: the structural subsystem (representing the main system of carrying and functional elements), the drive subsystem (representing the drives, actuators and energy sources) and the control subsystem (representing the sensors, controllers, signal buses and informations subsystem). Optimally linking mentioned attributes it is possibly to obtain the optimal design solution. It corresponds to certain approaches in mechatronics design understood as creating the system of specified subsystems (including the mechanical one and the electric one). In the presented work will be described the formal aspects of the integrated approach in the designing process. They will be also illustrated the practical results of introducing the proposed approach. These results are considered with the possibility of application the sophisticated tools of analysis like multi-agents theory. It is also possible to show the consequences of this approach for the CAD/CAE process. The integrated approach creates the theoretical platform for these informatics solutions. Finally one should point out the possibility of linking, in one designing process, informatics tools considered with designing and analysis of control subsystem.
Optimality of the Machining Process Based on the Mutual Influence of Design and Technological Dimension Relations
Authors: Toca Alexei , Stingaci Ion
Published: October 2014

In the given work it is shown, that at machining the technological dimensional structures are optimum if they are similar to the design dimensional structure of a detail. The conditions of the locating and fastening, and also some technical requirements interfere achievements of similarity. In these cases the directed change of the design dimensional structure of a detail is recommended due to recalculation of the sizes. From this point of view creation of technological process represents a compromise of mutual approche of the dimensional structures of a detail and of a technological system. Technological process may be built from operation elements, but they (the operation elements) do not have the necessary characteristics to create the dimensional structures. These characteristics are not formed during decomposition because the relevant details dimensional structure is not taken into account. The most appropriate entity as element of which may be built the technological process is a technological mounting. The mounting has a dimensional structure and includes the communication elements - the sizes up to locating surfaces Thus, the dimensional designing of technological processes results in optimality if it is possible to achieve the similarity of design and technological dimensional structures in the following order: creation of the blank's dimensional structure similar to the detail's dimensional structure; formation of optimum technological dimensional links of the first technological operations or mounting (roughing) by resizing if necessary of the blank and of the detail; formation of optimum technological dimensional links on the subsequent technological operations or mounting by resizing if necessary of the detail in progress; formation of optimum technological dimensional links on the final technological operations or mounting by resizing if necessary the detail; calculation of the minimal machining allowances; the dimensional analysis of technology with calculation of the operational sizes, their tolerances and limit deviations; formation of drawings of the blank.
Augmented Reality Aided 3D Modelling
Authors: Petruse Radu Emanuil , Bondrea Ioan , Sacco Marco , Mottura Stefano
Published: October 2014

The purpose of the article is to introduce possibilities of using Augmented Reality instructions in order to better understand technical drawings. The aim of these instructions based on 3D models is to create AR training applications and analyze their impact on the users. These instructions consist in a 3D model, superimposed over the technical drawing. The AR application also offers step by step instructions for 3D modelling in CAD software, which are very useful in creating the 3D model starting from a technical drawing. The AR application was tested by students from the Faculty of Engineering in Sibiu, obtaining great improvements in their 3D modelling times. The results of a survey that the students completed reveal that the AR modelling instructions also aids their spatial visualization capability.
Contextual Factors and Knowledge Sharing Motivation: A Research Framework
Authors: Rusu Gabriela , Avasilcai Silvia
Published: October 2014

A high level of human resources motivation to share knowledge acquired during training programs or other training activities may be crucial for companies in achieving targets for customers and high organizational outcomes. The recent investigations of the roles of socio-technical, cultural and non-work factors and the technological development underlined the importance of the organizational context factors as outstanding drivers for employees motivation to share knowledge among their colleagues and to improve work performance. This article conducts a literature review and aims to identify the contextual factors determining employees motivation for exchanging knowledge at the workplace and, thus, improving the overall organizational performance. There will be also proposed the dimensions of motivation for knowledge sharing taking into account the distinction between intrinsic and extrinsic motivation, based on the self-determination theory (SDT). Therefore, by analyzing the types of motivation according to self-determination theory, it is highlighted the importance of contextual factors in increasing knowledge sharing motivation in organizations. In this paper, we try to provide a framework to analyze the role of intrinsic and extrinsic motivation in determining a high level of motivation to share knowledge, improving work performance and increasing organizational outcomes. Within this view, the research aims to provide an integrative research framework and to underline the tie between the most significant dimensions of organizational context influencing employees knowledge-sharing motivation in industrial firms. The new research framework resulted from identifying significant contextual factors which influence employees motivation to share knowledge will provide a new direction to improving work activities and to foster the performance level at the workplace. The selection of the relevant dimensions integrated into the research framework will be used for a further quantitative research applied to employees working in industrial firms from the North-East Region of Romania. The investigation proposed brings into light a useful approach for knowledge management, emphasizing the importance of establishing the most important organizational context factors which determine employees motivation to communicate knowledge among work colleagues, demonstrating also the contribution to improving job performance.
The current framework can provide important insights for managers and academia in order to understand the importance of establishing a relationship between contextual factors influencing employees motivation to share knowledge and job performance.
Microstructure Researches of Metallic Composite Foams Based on AlMg Alloys
Authors: Bălţătescu Oana , Nuţescu Catalina , Rusu Ioan , Roman Costel , Carcea Ioan
Published: October 2014

Composite materials are the most advanced class of materials invented and produced by humans in modern times as well as a challenge for the future in the field of scientific and technological performance. They are made up of at least two phases of different nature which are so combined to form a new material with a superior combination of properties. They are generally materials with unusual performances on the relationship between properties and specific gravity. Composites are multiphase materials with distinct and well-defined interface between the constituent phases ensuring a transfer of property but can lead to obtaining a product with exceptional performance from the starting material. In this paper we have focused research on Al-Mg alloys with magnesium and silicon carbide (SiC). Stabilized Aluminium Foams (SAF) are new class of materials with low densities and novel physical, mechanical, thermal, electrical and acoustic properties. They offer potential for lightweight structures, for energy absorption, and for thermal management; and some of them, at least, are cheap. Metal foams offer significant performance gains in light, stiff structures, for the efficient absorption of energy, for thermal management and perhaps for acoustic control and other, more specialized, applications. They are recyclable and nontoxic. They hold particular promise for market penetration in applications in which several of these features are exploited simultaneously. The paper presents some results related to the research of metallic foams based on AlMg10 metallic alloy obtained by melt bubbled C4H10 addition of SiC particles. Microsrtucture of these foams is analyzed by using (SEM) Scanning Electron Microscope, laying out the network of pores imbued into each others developed around SiC particles and other issues microstructural characteristics.
The Cost to Quality Ratio in Terms of Voyage Energy Efficiency
Authors: Acomi Nicoleta , Acomi Ovidiu Cristian , Bostina Alina Lucia , Bostina Aurel
Published: October 2014

Shipping is permanently engaged in efforts to regulate the voyage energy efficiency and to control the marine GHG emissions. In order to achieve this, the International Maritime Organization (IMO) has developed a series of technical and operational measures. The Energy Efficiency Operational Index is one of the operational measures that can be used as a monitoring tool for the voyage optimization and represents the mass of CO2 emitted per unit of transport work. The purpose of this study is to analyze the competitiveness of using different types of marine fuels during the voyage and also to emphasize their influence over the Energy Efficiency Operational Index. The emissions from ships are directly proportional to the bunker consumption and with its quality, and this paper presents the Energy Efficiency Operational Index value for one complete voyage, varying the type of fuel for different legs for the main consumers: main engine, diesel generators, boiler and inert gas generator. The results consist in the cost to quality ratio, where the cost is the sum of money spent for different types of fuel and the quality is the ships Energy Efficiency Operational Index. The cost-to-quality ratio is presented in graphs in order to allow the ship-owner to choose the solution of protecting the marine environment, acting over the EEOI, based on the cost involved.
Symbiosis Process in Business Ecosystem
Authors: Galateanu Avram Elena , Avasilcai Silvia
Published: October 2014

The business ecosystems domain emerged as result to the necessity of assessment of new economic procedures and mechanisms between the economic agents. Defined as a community of interrelated agents, a business ecosystems approach can emphasize the most important features of modern economy. The main purpose of this paper is to provide a comparative analysis of business ecosystems with biological ones in order to identify the most important internal features which can describe the symbiosis process. In biological field, the symbiosis is defined as an association of individuals from different type of species. In the business field, this form of association is defined in terms of co-evolution and cooperation. From this point of view it is important to analyze main species who are involved into this type of relations. The starting point of this research is to define reference dimension whose knowledge is important in order to understand involved entities. At this step the concept of innovation will be considered as knowledge reference. The research method will be conducted based on the identification of different categories of elements, individuals and their integration into specific species. This integration will be realized by grouping individuals according to analyzed common features. The foreseen result is to highlight how the individuals knowledge about innovation contributes to the common vision of the entire group. The next step of the research framework will provide a comparative analysis between the established groups of individuals. The main outcome of this research is to provide a new model of reintegration of individuals from different domains of activity not limited by organizational boundaries.
As result, this paper will provide a framework for understanding the symbiosis from two points of views: the fusion process between the agents and the knowledge transfer as its result.
Changes in the Structure and Properties of the Steel S700MC by Heat Treatment
Authors: Górka Jacek
Published: October 2014

In order to determine the effect on the properties of precipitation processes conducted S700MC steel heat treatment consisting of annealed steel test temperatures: 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200 and 1300 °C. Sample obtained after the heat treatment process has been tested by Charpy V toughness, metallographic testing and measurement of Vickers hardness. In order to determine the strength and plastic properties of simulated heat affected zone S700MC steel material tensile test was carried out according to PN-EN 10002-1 for round samples. The study showed that the stability of bainitic structure is maintained to a temperature of 600 °C. In the temperature range 700 to 1000 °C, the test steel with ferritic-pearlitic structure with a small grain growth. The heat treatment above 1000 °C increases the amount of ferrite in the structure, and a strong growth of grain size. Tested steel retains its strength and hardness properties of the heat treatment does not exceed 600 °C. When this temperature is exceeded the tensile strength and hardness are significantly lower in comparison to the base material. Temperatures warm temperatures corresponding to the normalization cause loss of property obtained in the initial thermomechanical rolling process. It is impossible to return to the property upon cooling to ambient temperature, thus constantly this group should not be hot forming.
Researches on Fracture Surfaces Electrochemically Charged with Hydrogen
Authors: Parfene Catalina Sorina , Solomon Gheorghe , Voiculescu Ionelia , Vasile Ion Mihai , Ionita Daniela
Published: October 2014

The present paper deals with the morphological alteration of fracture surfaces determined by hydrogen in the case of hydrogen based steels, through electrochemical methods as compared with similar samples of surfaces electrochemically uncharged or with welding deposits created by means of cellulose coated electrodes. Cellulose electrodes allow larger hydrogen quantities to be introduced into the metal deposited during the welding process. Hence, specific fractographic aspects are highlighted in view of interpreting prospective alterations caused by hydrogen based steels (13CrMo4.5 and S235 JR).
Laser Annealing of 8YSZ Powders
Authors: Grabowski Andrzej , Moskal Grzegorz , Kępińska Mirosława
Published: October 2014

In the article are presented investigations of the reflectance and the absorption coefficient of yttrium partially stabilized zirconia (YPSZ), for 10,6μm wavelength electromagnetic radiation as well as for the wavelengths in the range of 0,5-1,1μm. Based on an experimentally obtained absorption coefficients, the amount of laser power densities absorbed within YPSZ was calculated. Also, experimental investigations with Disk laser and CO2 laser radiation annealing were conducted. It was shown that for different lasers wavelengths and for the same laser beam intensities the microstructural changes in YPSZ are different.
High Manganese Austenitic X6MnSiAlNbTi26-3-3 Steel - Characteristic, Structures and Properties
Authors: Borek Wojciech , Czaja Małgorzata , Labisz Krzysztof , Tański Tomasz , Krupiński Mariusz , Rusz Stanislav
Published: October 2014

The aim of this paper is to determine the high-manganese austenite propensity to twinning induced by the cold working and its effect on structure and mechanical properties, and especially the strain energy per unit volume of new-developed high-manganese Fe – Mn – (Al, Si) investigated steel with various structures after their thermo-mechanical treatments. The new-developed high-manganese steel provides an extensive potential for automotive industries through exhibiting the twinning induced plasticity (TWIP) and transformation induced plasticity (TRIP) mechanisms. TWIP steels not only show excellent strength, but also have excellent formability due to twinning, thereby leading to excellent combination of strength, ductility, and formability over conventional dual phase steels or transformation induced plasticity TRIP steels.
The microstructure evolution in successive stages of deformation was determined in metallographic investigations using light, scanning and transmission electron microscopies as well as X-ray diffraction methods.
Modeling of the Minehunters Hull Strenght
Authors: Grządziela Andrzej , Szturomski Bogdan , Kluczyk Marcin
Published: October 2014

The paper presents problems of modeling the ship’s hull subjected to the load of shock wave associated with non-contact underwater explosion. The article presents equations for describing the parameters of shock wave subjected to an impulse load. The paper presents a proposal of identification of a degree of hazard the ship’s hull forced from underwater explosion. A theoretical analysis was made of influence of changes of hull structure in vicinity of hull. Modeled signals and hull structure were recognized within sensitive symptoms of three sub models: model of hull structure, model of impact and model of propulsion system. All sub models allow testing forces and their responses in vibration spectrum using SIMULINK software and FEM models. The results of testing allowed performing simulations of a similar nature to the actual loads of underwater explosions. Virtual model of the hull of the ship responds in a similar manner to the real impacts.
Study of Various Thin Films Obtained by Several Deposition Methods
Authors: Tugui Catalin Andrei , Vizureanu Petrică , Nejneru Carmen , Perju Manuela Cristina , Achiţei Dragos , Axinte Mihai
Published: October 2014

Properties of metallic materials can be improved with special materials depositions. Materials deposited on base materials are qualitatively better than the base materials, with a better hydroabrasive wear and corrosion resistance, also with a chemical attack or mechanical stress improved resistance.The thin layer deposition represents depositions (coatings) with hardening, lubricating, or decorative function, having a thickness of less than 10 micrometers.Such special materials are used in cutting-edge technology, such as nuclear turbines and turbine airplanes, space crafts or submarines, which must withstand high temperature, erosion and different chemical attacks.Along with traditional technologies for obtaining coatings, we assist in the development, improvement and expansion of deposition modern techniques, which ensures high purity and adhesion through a wide variety of processes. These thin layer coated materials should not be very expensive from the economic point of view. That is why, scientists are looking to find out the easiest deposition methods and also with great technical efficiency.In this paper we presented several methods of thin film deposition. We also highlighted some of the advantages and disadvantages of some deposition methods.
Modification of Heat Flow Parameters during the Ceramic Assisted Microwave Heating of HDPE
Authors: Savu Ionel Dănuț
Published: October 2014

Microwave technology is more often used in large number of application. Heating polymers by microwave technology is met from domestic o industrial applications and the influences brought by the heating source, the impact between the microwaves and the polymer, to the base material is necessary to be well known to avoid different types of failure of the pieces. HDPE is polymer often used in application with interaction between material and microwaves. Because of that the analysis of the influence of such interaction on the flowing characteristics of the HDPE is proposed in this paper. Experimental programme was applied to HDPE 100 and HDPE 80, both heated by using mono-directional microwave beam with different sets of parameters (factorial experiment principles were used to establish the heating parameters). Plasticity characteristics of the heated material, as elongation and relaxation modulus, were determined by using thermal analysis. It has been recorded important influences of the heating process on the surface in contact with the ceramic powder that was used as microwave absorber. The DSC analysis revealed a decreasing of the elongation with about 16% and decreasing of the relaxation modulus with amount up to 18%, for the material located at the interface between the polymer and the ceramic powder. Each 2 mm from the interface to the interior of the polymer brought an intensity of the modification up to 15% of the values recorded for the interface. After 6 mm from the interface the intensity of the modification decreases very fast. By using DSC thermal analysis it has been analysed the crystallization rate of the polymer modified by the microwave heating and high rates were recorded. About 12% difference between the relaxation modulus of the heated and non-heated HDPE and that means local ageing transformation of the HDPE.
Modeling and Experimental Research Regarding the Temperature Distribution along Curved Cutting Edges
Authors: Baroiu Nicuşor , Boazu Doina , Berbinschi Silviu , Teodor Virgil
Published: October 2014

The curved cutting edge determines a variable chip thickness that leads to various may energetically load along the cutting edge. For twist drill with curved cutting edges, the machining speed variation along the major cutting edge is significant. The points belong to the drills periphery work with an increased machining speed. The thick of the detached chip by these cutting zones downwards to the periphery, versus the thick corresponding to the zones at the drills axis, may leads, in some conditions, to the evenness of the energetically load along the cutting edge, with direct influence regarding the cutting tools wearing mechanism. In this paper are presented modeling with finite elements developed in the Ansys Workbench environment, regarding the energetically load and the temperature state along the cutting edge with variable working angle, characteristic for twist drills with curved cutting edges. The modeling was made comparative with the drill with straight lined cutting edges, for the same working conditions. In the same time, presents an experimental record of an actual process. It was recorded the temperature along the cutting edge with a variable working angle in a turning process with transversal feed. There are presented results of the finite element modeling and of the experiment that simulated the cutting process at drilling. The experimental results of the finite element modeling confirm the trend for temperature evenness along the cutting edge with variable working angle regarding the drills with straight-line cutting edge.
Influence of the Tool Clearances on the Dimensional Accuracy of Mini Drawn Parts
Authors: Brabie Gheorghe , Chirita Bogdan , Costache Elena , Teaca Robert Stefanut
Published: October 2014

The mini deep drawing is a cold forming process applied in order to realize small parts having dimensions smaller than 20 mm. In the case of such process the small thickness of sheet and the small dimensions of parts are the most important factors that influence the process parameters and can affect the accuracy and quality of the produced mini - parts. A proper clearance between the working tools components is also a very important factor that can permit to obtain mini drawn parts in accordance with their theoretical profile. The present paper analyses the results of investigations made by experiment and simulation concerning the influence of tool clearances values on the accuracy of dimensions in the case of mini scale cylindrical drawn cups made from thin sheets. The deviations from the cups theoretical profile (wall inclination, variation of part diameter) that can occur during deep drawing of such sheets were especially analyzed in the paper.
Welding of Inconel 625 Using a Direct Diode Laser
Authors: Janicki Damian
Published: October 2014

In this study, a high power direct diode laser (HPDDL), with a rectangular laser beam spot, was used for conduction mode welding of Inconel 625 sheets (0.8 mm thick). The influence of laser butt welding parameters on weld quality and mechanical properties of test joints was studied. The quality and mechanical properties of the joints were determined by means of tensile and bending tests, and micro hardness tests, and also metallographic examinations. The minimum heat input required to achieve full penetration butt welded joints was found to be 60 J/mm. The joints exhibited comparable yield and about 15 % lower ultimate tensile strength when compared with that of the base metal.
An Investigation of Forces during Roller Forming Process
Authors: Kagzi Shakil A. , Raval Harit K.
Published: October 2014

The tubular sections or shells for forming channels, drums, tanks or pressure vessel are manufactured by bending plates generally through three-roller bending machine and then welding the ends of bent plate to form a cylinder or cone. Force exerted on rollers during bending is one of the important criteria which must not exceed the capacity of bending machine. Secondly, Total bender capacity must be utilised during bending of desired curvature, which reduces number of passes and hence time required to attain desired curvature. Thus, it necessary to estimate the forces during bending, based on the roller position, so that it does not exceeds the bender capacity and simultaneously reduces number of passes. In this regards, some analytical models are available to predict the forces during three roller bending process with assumption of constant bend radius during bending. In fact, the radius continuously changes during bending operation which affects the magnitude and the direction of the forces exerted on the roller. An attempt is made to simulate the roller bending using FEA. Variation of curvature of plate and effect of various parameters such as plate thickness, bottom roller inclination and top roller inclination on bending forces during cylindrical and conical bending operation are studied using FEA analysis.
The Influence of the Punch Speed on the Welding Line Movement during Deep Drawing in Case of Tailor Welding Blanks
Authors: Albut Aurelian
Published: October 2014

The work presented in this paper refers to numerical simulation related to deep drawing of three parts having different geometry, as follows: square shape, cylindrical shape and semispherical shape. The current paper is trying to prove out the important role of the punch speed on the welding line displacement during the forming process. The punch speed influence is testes for the fallowing values: 100, 300, 600, 800 and 1000 mm/s. The punch stroke is 25 mm, which is the safe drawing depth for all three selected shapes. The parts are made from tailor welded blanks, having the welding line positioned as axis of symmetry. It must be mentioned that both materials from the welded structure are having the same thickness (1mm). The Dynaform 5.8.1 software is used to simulate the forming process. The part obtained after each simulation is analyzed and measured to quantify the displacement of the welding line. The welding line behave differently for each tested punch speed and also for each part shape. All the parameters are maintained fixed except the punch speed. The obtained results for those three shapes were compared to realise the behaviour of the tailor welded blanks during deep drawing process. In the final part of this paper conclusions regarding the influence of the punch speed and of the part shape on the welding line movements are presented.
Research of Changeability of Cutting Process Parameters at Turning of the Shaped Surfaces
Authors: Ivchenko Tatiana , Petryaeva Irina , Grubka Roman
Published: October 2014

Conformities to law of changeability of the tool geometrical parameters, parameters of сut section, parameter of the chip formation, cutting forces, cutting temperature and machining surface roughness at machining of the shaped surfaces are set.
There is researched character of change of the working edge angle, cutting face edge angle, width and thickness of cut section, cutting speed on position of blade top on the convex and concave shaped surface.
The analytical dependences of the chip contraction coefficient, cutting forces, cutting temperature and machining surface roughness on the cutting speed and feed are certain. The method of determination of the cutting forces, thermal streams and cutting temperature at turning of the shaped surfaces is created taking into account changeability of the geometrical parameters and parameters of сut section. There are set coefficients, which allow expecting these parameters in any point of the convex and concave shaped surfaces.
The method of account of the cutting process parameters changeability at optimization of the cutting regimes at turning of the shaped surfaces on the criterion of maximum productivity is developed. With the use of method of the linear programming analytical dependences of the optimum-cutting regime from the turning parameters taking into account variable limitations on cutting forces, cutting temperature and machining surface roughness are definite.
Improvement of Dynamic Properties of Thin Disc Cutting Tools on the Basis of Controlled Impact
Authors: Mikhaylov Alexander , Dolhykh Hanna
Published: October 2014

This work is aimed at improvement of durability of especially thin disc tools, by means of controlling their dynamic parameters. It was found out that it is necessary to design tools and methods of reducing oscillations of the tool’s structure that could allow designing tools with thin and especially thin cutting pieces, ensuring the specified parameters of its durability, cutting precision and improvement of cutting modes. The performed investigations allow reducing substantially the cut’s width and ensuring the prescribed parameters of the tool’s durability, thus improving the overall technical and economic parameters of blanks cutting.
Researches in Cutting Parameters Influence on the Surface Quality in Worms Manufacturing with Whirling Thread Cutting
Authors: Creţu Gheorghe
Published: October 2014

1. Theoretical aspects
Choice of Lubricating and Cooling Action of Cutting Fluids by the Thermomechanical Model
Authors: Mikhaylov Alexander , Sydorova Elena , Navka Ilya
Published: October 2014

The use of cutting fluids in turning can change thermomechanical loading of cutting tools. Currently, manufacturers provide a wide range of cutting fluids, which have different combinations of lubricating and cooling properties. Depending on cutting conditions, this combination can reduce tool wear in different degrees, and, in some cases, to even increase it. Therefore, an effective choice of cutting fluids requires a considerable amount of experiments, which requires cost and time. To solve this problem in the software SIMULIA/Abaqus Explicit 6.10 was developed thermomechanical model of the turning process by cutting tools with PVD-coating, which allows simulating the effect of any combination of cooling and lubricating action. An Arbitrary Lagrangian-Eulerian formulation method was used in the modeling. Under the lubricating and cooling action is understood the final result of interaction of cutting fluids with the cutting zone. Modeling of lubricating action of cutting fluid is performed by introducing into the model corresponding average coefficient of friction in the contact zone of cutting tool, worked material and cutting fluid. Modeling of cooling action of cutting fluids is implemented through the introduction of the heat transfer coefficient, calculated on the basis of cutting conditions and thermo-physical properties of cutting fluids. As an example, turning of austenitic stainless steel X10CrNiTi18 by carbide cutting insert with TiN-coating for a predetermined cutting condition was examined. A selection of cutting fluids of the proposed range, formulations of which have different combinations of cooling and lubricating properties ("Unizor-M", "Ferrobetol-M", "EkoEM-1", "STARCUT E9", "SAFECUT M120") was accomplished through the simulation model and the calculated data contact stresses. Experimental studies have confirmed the validity of this choice by comparing the rate of flank tool wear in the using different cutting fluids. The rate of wear was determined by surface micrographs of flank tool. An application of the recommended cutting fluid "SAFECUT M120" has reduced wear by 4 times as compared with the application of the "Ferrobetol-M", the use of which has shown the highest wear. The model developed can be used for selecting a predetermined range of cutting fluids, in determining the optimal combination of lubricating and cooling actions for establishing the required characteristics of cutting fluid or in developing new formulations of cutting fluids.
Steel Welding with Micro-Jet Injector
Authors: Węgrzyn Tomasz , Piwnik Jan , Horzela Izabela , Majewski Wojciech
Published: October 2014

The article focuses on mild steel welding and covers the new possibilities of that method. Since 2011 innovate welding technology based on micro-jet cooling just after welding is being checked. Weld metal deposit (WMD) was carried out for standard MIG welding and for new welding method with micro-jet cooling. A very high percentage of acicular ferrite (AF) in WMD was gettable (55-75%) for low alloy welding with micro-jet cooling injector. This beneficial structure (very high amount of AF) is unusual to observe in WMD in other welding methods. This method is very promising mainly due to the significant improvement of weld quality and reduces costs. Furthermore impact toughness and strengths of WMD were carried out. The present paper aims at outlining same of the recent innovations in MIG welding which represent steps ahead to achieve the objectives outlined above.
High Power Diode Laser Application for Metals Surface Treatment Based on Wear Resistance Investigation
Authors: Labisz Krzysztof , Jonda Ewa , Tański Tomasz , Borek Wojciech , Czaja Małgorzata
Published: October 2014

This paper presents the results of laser remelting influence on structure and properties of the surface of the AlSi9Cu2 aluminium cast alloy as well as X40CrMoV5-1 and 32CrMoV12-28 hot work tool steels, carried out using the high power diode laser (HPDL). Structure changes were determined in the work, especially structure of the surface after wear resistance test. Also hardness investigation of the different remelting areas was performed. The reason of this work was also to determine the laser treatment parameters, particularly the laser power, to achieve a good layer hardness for protection of this constructional and tool materials from losing their work stability and to make the material surface more resistant for work extreme conditions. Tungsten carbide and boron nitride powder was used for alloying. The goal of this work was also to determine technical and technological conditions for remelting the surface layer with HPDL. The remelted layers which were formed on the surface of the investigated aluminium and steels were examined metallographic and analysed using a hardness and wear resistance testers. Key words: Wear resistance, HPDL treatment, aluminium alloys, tool steel, remelting, alloying, surface treatment, boron nitride, tungsten carbide.
Advantages of Spectrally Analyzed Data: Stochastic Models for Automotive Measured Parameters
Authors: Vilău Radu , Marinescu Marin , Alexa Octavian , Oloeriu Florin , Truta Marian
Published: October 2014

The paper deals with a new approach in data analysis of a measured mechanical parameter. The classic approach is mainly based on the deterministic statistics that cant cover the whole field of a complete analysis. The stochastic approach, to be used in this paper, offers far more information about the mechanical parameter and can take into account the non-linearity of the signal, eventually, the mechanical parameter itself. Starting from the point of view that, in real life, there is no steady evolution of any parameter, we decide to take into account the importance of the non-linear components of any signal. After e thorough investigation, we hope we could make the difference between the noise, as non-linear components of the measured parameter, and the useful non-linear components (e.g. important shocks, typically met within a vehicles transmission). Using the stochastic modeling procedures, we aimed at issuing comprehensive, accurate and valuable dynamic models of the phenomenon. These models cam be used in a large variety of situations, from describing the process, to evaluating the health of a mechanical system and to controlling a real-time process based on the pre-set models (previously drawing a map of the systems normal behavior and permanently assessing the deviation from it and acting accordingly). The data were measured within the transmission system of a military vehicle. Specifically, we have gathered information about torque and angular speed of different shafts of the driveline. As everybody knows, the power flows within any vehicles transmission in transient modes mainly and it is accompanied by plenty of noise. It is rather challenging to separate (filter) the useful signal form the noise but, on the other hand, it is the only way to achieve useful data. Therefore, a spectral analysis is a must, but not the conventional one, which has its drawbacks, but a multi-spectral one, which is able to insulate the noise. Moreover, starting from the analysis developed with this method, mathematical models, both in discrete and continuos time can be achieved. It is easy to notice that the models that we have achieved are featured by a very good accuracy. We could push the data processing even further, getting generalized models that provide the needs we have mentioned before, with respect to the mapping of a normal (averaged) behavior of a system, to be used in controlling procedures.
Modelling of an Electric Circuit’s Type Influence on Dynamic Flexibility of System with Passive Vibration Damping
Authors: Płaczek Marek
Published: October 2014

Paper presents a proposal of mathematical algorithm used for analysis of influence of type of selected passive electric circuit on dynamic flexibility of system with piezoelectric transducer used for shunting vibration damping. Mathematical model of one-dimensional, vibrating system with shunted piezoelectric transducer is proposed and using approximate method the systems dynamic flexibility is calculated. Influence of type of used passive electric circuit on the systems dynamic flexibility are analysed. The purpose of this work is to obtain a functional mathematical tool that can be used to design such kind of systems obtaining the best efficiency of their work. In order to make it possible it is necessary to know the influence of type and parameters of elements of chosen passive electric circuit on the systems characteristic. In order to realize the assumed aims, the discrete-continuous mathematical model of the considered system is created. It is not possible to use an exact methods to analyse such kind of one-dimensional, vibrating systems with piezoelectric transducers, this is why the approximate method is used.
Modelling of Hardness Prediction of Alloyed Copper Using Artificial Neural Networks Applications
Authors: Konieczny Jarosław , Chmielnicki Blazej , Tomiczek Błażej
Published: October 2014

The aim of the work is to employ the artificial neural networks for prediction of hardness of the alloyed copper like CuTi, CuFe, CuCr and CuNiSi. In this paper it has been presented an original trial of prediction of the required hardness of the alloyed copper like CuTi, CuFe, CuCr and CuNiSi. Artificial neural networks, can be applied for predicting the effect of the chemical composition, parameters of heat treatment and cold working deformation degree on the hardness. It has been assumed that the artificial neural networks can be used to assign the relationship between the chemical compositions of alloyed copper, temperature and time of solution heat treatment, degree of cold working deformation and temperature and time of ageing. In order to determine the relationship it has been necessary to work out a suitable calculation model. It has been proved that employment of genetic algorithm to selection of input neurons can be very useful tool to improve artificial neural network calculation results. The attempt to use the artificial neural networks for predicting the effect of the chemical composition and parameters of heat treatment and cold working deformation degree on the hardness succeeded, as the level of the obtained results was acceptable. Worked out model should be used for prediction of hardness only in particular groups of alloyed copper, mostly because of the discontinuous character of input data. The results of research make it possible to calculate with a certain admissible error the hardness value basing on combinations of concentrations of the particular elements, heat treatment parameters and cold working deformation degree.
Control of Vibration of Mechanical Systems Using Electrical Subsystems
Authors: Białas Katarzyna , Buchacz Andrzej , Gałęziowski Damian
Published: October 2014

The reduction or elimination of undesired vibration can be achieved by applying various methods. The most commonly applied methods are: passive, semi-active and active.This work presents methods of reduction of the vibration of mechanical systems by means of active elements as well as examples of implementation of reduction of vibration by means of electrical elements. This work also introduces a structural and parametric synthesis, which can be defined as the design of systems meeting specific requirements. These requirements refer to the frequency values of the systems vibration. The presented approach i.e. a non-classical synthetic method applied in designing mechanical systems, one (as early as at the design and construction stage) may verify future systems. As a result of the synthesis one can obtain the structure and parameters of the system of required properties. The synthesis may also be applied to modify the already existing systems in order to achieve a desired result.
Protection of Hydraulic Systems against Dynamic Loads Using Multi-Valve Approach
Authors: Gwiazda Aleksander , Sękala Agnieszka , Banaś Wacław , Monica Zbigniew
Published: October 2014

The paper presents the method of designing equipment for protection the hydraulic system, and particularly hydraulic machines, against dynamic loads. The example of such machine is a powered mining support. A support must work in the conditions related with rock crumps what causes large and quick energy releasing. The designing process bases on the integrated approach what let taking into consideration all needed elements of this process [1,. Each of the elements of the design process could be an independent design agent which could find its solution both in CAD technique and other modeling tools [3,4]. Moreover in the paper is presented the results of computer analysis of the presented solution. This design solution bases on the application, in the protected hydraulic system, two complementary valves: the quick-release valve and the large-caliber one. Analysis of this valve system allow to state that this technical solution should protect a hydraulic system against dynamic loads of any energy.
Theoretical Approach on Internal Combustion Engines Using Multivariable Procedures
Authors: Oloeriu Florin , Mocian Oana , Marinescu Marin , Grosu Dănuţ , Ilie Constantin
Published: October 2014

The paper highlights the main possibilities available when studying how the vehicles engine operate using algorithms specific to the multivariate statistics. A particular example of studying the engines behavior is represented by the diagnosis activity performed onto the vehicle, an activity that a special attention is being paid to throughout the paper. To this purpose, during the tests we have intentionally caused certain malfunctions to the engine. Circuit breakdowns were intentionally caused on various electric circuits that connect sensors and actuators to ECU. Fitting modern vehicles with electronic control systems offers the possibility for computerized approach of various maintenance operations onto its mechatronic components (sensors, actuators). These components are part of those electronic systems. Such an approach includes onboard simulation of various malfunctions that may occur during normal operation of vehicles. The procedure which is currently presented in the paper herein is about generating controlled malfunctions, using the sensors connector, a signal that is specifically varied towards the electronic control unit (ECU). Thus the ECU will interpret that the system that it is managing indicates a vehicle malfunction. .