Термины физики в татарском языке: автореферат диссертации на соискание ученой степени к.филол.н.: специальность 10.02.02

The approach taken in this paper is twofold. First manufacturing environment is simplified for the purposes of planning and control without losing any of the essential characteristics. Second, a simple GT model is applied to the shop floor area and real time MRP is applied to the assembly area. The aim of this study is to develop and compare with a simulation of similar proposal except that jobshop is used in the shop floor area instead. The variable factors in both models were the set up time to operation time ratio and the intensity of the loading on the machines. In the highly loaded situations, the GT model faired better than the job shop model. However, for low loaded situations the performances of the two models were similar

Optimal design of MR damper via finite element analyses of fluid dynamic and magnetic field

In the last decade many researchers have been carried out on semi-active control systems, a large number of academic publications have been presented. Semi-active control systems which are used the magnetic field controlled fluid have been shown significant improvements by the researchers. In the study, a design optimization method that has been carried out for the objectives of target damper force and maximum magnetic flux density of an MR damper has been presented. Finite element methods, electromagnetic analysis of magnetic field and CFD analysis of MR flow, have been used to obtain optimal value of design parameters. The new approach that is use of magnetic field and MR flow together and simultaneously has specified optimal design values. Two optimal design of MR damper obtained have been verified with experimental study by manufacturing and testing of the dampers. (C) 2012 Elsevier Ltd. All rights reserved

Evaluation of sintering temperature and tribological properties of ceramic materials with Cr2O3, SiO2 and MnO2 additive compounds

Advanced ceramics such as alumina are widely in use in the design of components for high engineering applications mainly because of their high wear resistance, high compressive strength, low specific density and high temperature capability. Processing and manufacturing of pure alumina products is a difficult and expensive task. Therefore, additional compounds are added to alumina to achieve a more complex component design and to minimise the product processing and manufacturing costs, This paper examines the effects of speed, load values and the addition of Cr2O3, SiO2 and MnO2 compounds on the friction and wear behaviour of alumina ceramic. Wear tests for alumina and alumina samples containing w1.5% Cr2O3 w3% SiO2 and w1.5% MnO2 compounds was carried out on a pin-on-disc machine. Tribological tests were under 2.5, 5 and 10N loads and at 0.5, 0.75 and 1 m/Sec speeds. The specific wear rates were deduced from mass loss. The wear rate for alumina without additional compounds was in the order of 10(-8) to 10(-7)mm(2)/N, while the wear rate values for alumina with additional compounds were in the order of 10(-6). Moreover, the wear rate showed more sensitivity to the applied load, particularly at low sliding speeds. Furthermore, it is concluded that a 20 per cent decrease in the sintering temperature resulted in 300 per cent increase in the specific wear rate of alumina ceramic material

Geometrical optimisation of vehicle shock dampers with magnetorheological fluid

Magnetorheological (MR) dampers have attracted interest from suspension designers and researchers because of their variable damping feature, mechanical simplicity, robustness, low power consumption and fast response. Therefore, optimisation of such devices is of particular interest to achieve optimal vibration control. This study deals with the geometrical optimisation of an MR shock damper using Taguchi experimental design approach. The optimal solutions of the MR damper were evaluated using analytical equations, which give the dynamic range of the damper under consideration. Optimal geometrical values obtained provided most performance in consideration of other nine alternatives of Taguchi experimental design specified for the study

Comparison of the thermal stresses developed in diamond and advanced ceramic coating systems under thermal loading

Surface preparation techniques such as plasma spraying, physical vapour deposition and chemical vapour deposition have been used to make convenient material combinations for the use in high-technology requirements. High-temperature coating are used for two main functions. Either to protect a base metal against corrosion or erosion, or to minimise wear. A third function is to reduce the temperature of the base metal in the case of thermal barrier coatings. In this investigation, thermal and structural finite element analysis has been employed to analyse the level of stresses developed in coatings subjected to thermal loading. Diamond, Si3N4, Al2O3 and TiC coating systems were modelled. Coatings with NiAl interlayer material were also modelled. Nominal and shear stresses at the critical interface regions (film/interlayer/substrate)were obtained and compared. The results showed that the level of the thermal stresses is influenced by coating material, coating thickness, interlayer material thickness and the mismatch of the thermal and mechanical properties between coating and substrate materials. It is also concluded that the finite element technique can be used to optimise the design and processing of diamond and ceramic coatings. (C) 2000 Elsevier Science Ltd. All rights reserved

Influence of SiO2 and MnO2 additives on the dry friction and wear performance of Al2O3 ceramic

Alumina is widely selected in the design of components for high engineering applications mainly because of its high wear resistance, high compressive strength, low specific density and high temperature capability. Processing and manufacturing of pure alumina products is a difficult and expensive task. Therefore, additional compounds are added to alumina to reach more complex component design, to minimise the product processing and manufacturing costs. In this investigation we studied and explored the influence of additional compounds, speed and load values on the friction and wear behaviour of alumina ceramic. Wear tests for alumina and alumina samples contained w3% SiO2 and w1.5%MnO2, addition compounds was carried out with a pin-on-disc machine. Tribological tests were under 2.5, 5 and 10 N loads and at speeds of 0.5 and 1 m/s. The specific wear rates were deduced from mass loss. The wear rate for alumina without additional compounds was in the order of 10(-8) to 10(-7) mm(2)/N. while the wear rate values for alumina with additional compounds were in the order of 10(-6). Moreover, the wear rate showed more sensitivity to the applied load, particularly at low sliding speeds. (C) 2000 Elsevier Science Ltd. All rights reserved

Influence of SiO2 and MnO2 additives on the dry friction and wear performance of Al2O3 ceramic

Alumina is widely selected in the design of components for high engineering applications mainly because of its high wear resistance, high compressive strength, low specific density and high temperature capability. Processing and manufacturing of pure alumina products is a difficult and expensive task. Therefore, additional compounds are added to alumina to reach more complex component design, to minimise the product processing and manufacturing costs. In this investigation we studied and explored the influence of additional compounds, speed and load values on the friction and wear behaviour of alumina ceramic. Wear tests for alumina and alumina samples contained w3% SiO2 and w1.5%MnO2, addition compounds was carried out with a pin-on-disc machine. Tribological tests were under 2.5, 5 and 10 N loads and at speeds of 0.5 and 1 m/s. The specific wear rates were deduced from mass loss. The wear rate for alumina without additional compounds was in the order of 10(-8) to 10(-7) mm(2)/N. while the wear rate values for alumina with additional compounds were in the order of 10(-6). Moreover, the wear rate showed more sensitivity to the applied load, particularly at low sliding speeds. (C) 2000 Elsevier Science Ltd. All rights reserved

Use of the finite element technique to analyze the influence of coating materials, material phase state and the purity on the level of the developed thermal stresses in plasma coating systems under thermal loading conditions

In this investigation, a transient thermal and structure finite element solution has been employed to analyse the level of the thermal stresses developed in plasma coating systems subjected to thermal loading. Plasma coating is used for two main functions: either to protect a base metal against corrosion or erosion; or to minimize wear. A third function is to reduce the temperature of the base metal in the case of thermal barrier applications. In this work cubic, TZP, PSZ zirconia, polycrstalline alumina oxide, 85 and 98% pure alumina-tungsten substrate coating systems were modelled. Coatings with NiCoCrAlY interlayer material were also modelled. Nominal and shear stresses at the critical interface regions (film/interlayer/substrate) were obtained and compared. The results showed that the coating material phase and purity as well as interlayer material and the mismatch of the thermal and mechanical properties between coating and substrate materials influences the level of the thermal stresses. It is also concluded that the finite element technique can be used to optimise the design and the processing of ceramic coating systems. (C) 2001 Elsevier Science B.V. All rights reserved

Use of the finite element technique to analyze the influence of coating materials, material phase state and the purity on the level of the developed thermal stresses in plasma coating systems under thermal loading conditions

In this investigation, a transient thermal and structure finite element solution has been employed to analyse the level of the thermal stresses developed in plasma coating systems subjected to thermal loading. Plasma coating is used for two main functions: either to protect a base metal against corrosion or erosion; or to minimize wear. A third function is to reduce the temperature of the base metal in the case of thermal barrier applications. In this work cubic, TZP, PSZ zirconia, polycrstalline alumina oxide, 85 and 98% pure alumina-tungsten substrate coating systems were modelled. Coatings with NiCoCrAlY interlayer material were also modelled. Nominal and shear stresses at the critical interface regions (film/interlayer/substrate) were obtained and compared. The results showed that the coating material phase and purity as well as interlayer material and the mismatch of the thermal and mechanical properties between coating and substrate materials influences the level of the thermal stresses. It is also concluded that the finite element technique can be used to optimise the design and the processing of ceramic coating systems. (C) 2001 Elsevier Science B.V. All rights reserved