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EN
This study deals with the selection of optimum parameters for friction stir processing of Al alloy 6061-T6 reinforced with a hybrid nanoparticle (B4C and SiO2) in terms of their effect on the mechanical properties (hardness, tensile strength, and wear resistance) using Taguchi method. This work was carried out under four parameters each one running in three levels; rotational speeds (800, 1000 and 1200) rpm, travel speeds (10, 20, and 30) mm/min, holes depth (2, 2.5, and 3) mm, and mixing ratio of (SiO2/B4C) nanoparticles (1/1, 1/2, and 1/3), using L9 (34) Taguchi orthogonal array. Tensile strength and microhardness tests were conducted to evaluate the mechanical properties, in addition to the wear resistance test which is carried out using a pin-on-disk device. The microstructure was examined by optical microscopy, field emission scanning electron microscopy, and x-ray diffraction analysis. It was found that the highest tensile strength (223) MPa at 1200 rpm rotational speed, 30 mm/min traverse speed, 2.5 mm holes depth, and 1/2 (SiO2/B4C) nanoparticles mixing ratio, the highest hardness reached is (155) HV, then decreases in the direction of thermomechanically affected zone (TMAZ), heat affected zone (HAZ), and the base material at (1200) rpm rotational speed, (30) mm/min linear speed, a hole depth of (2) mm and (1/3) mixing ratio of (B4C/SiO2) nanoparticles. The wear behavior was of a mild type or an oxidative type at low loads (5 N), which became severe or metallic wear at higher loads (20 N) at fixed sliding time and speed. The (ANOVA) table has been used to determine which parameter is the most significant using MINITAB software.
EN
In the present study, the arithmetical mean roughness (Ra) values obtained as a result of drilling glass fiber reinforced polymer (GFRP) composite material produced in fiber orientation angles (0º/90º) with different drill bits in a 5-axis CNC controlled vertical machining center, were analyzed. The experimental design was applied with the Taguchi method. The drilling experiments were performed using Minitab 19 software according to the Taguchi L18 orthogonal array. The test results were evaluated based on the signal-to-noise (S/N) ratio. Two different drill bits (HSS and carbide), three different spindle speeds (750, 1000, 1500 rpm) and three different feed rates (0.05, 0.10, 0.15 mm/rev) were selected as the control factors. The effect levels of the control factors on Ra were found by applying analysis of variance (ANOVA). A confidence level of 95.62% was obtained with ANOVA analysis. The lowest Ra value was 1.279 μm at the spindle speed of 1500 rpm and the feed rate of 0.05 mm/rev using a carbide drill bit. The drill bit type was obtained as the parameter with the highest effect with a rate of 61.33%.
EN
This investigation effort offers multi-quality attributes optimization while turning of Inconel-600 superalloy. Taguchi's L9 orthogonal planning is implemented to review the upshot of governing aspects such as machining speed, feed rate, and depth of cut on vibrations and surface roughness (SR). To heighten all the three leading variables, the grey interactive exploration (GIE) is implemented. The grey interactive rating (GIR) is practiced as a multi-quality exclusive key (MQEK). The finest formation of central variables acquired from the investigational grades is cutting speed 500 m/min, feed rate 0.22 mm/rev and depth of cut 0.5 mm. ANOVA scrutiny signposts that feed rate is a crucial variable relating to the superiority yields. Products of endorsement pilots display that the ideal foremost variables developed the grey interactive rating from 0.6932 to 0.8138 for the numerous retorts. Scanning Electron Microscopic (SEM) scrutiny of cutting tool spectacles that fracture, chipping, abrasion and adhesion are the primary wear phenomena.
EN
Researchers are using different statistical techniques for process optimisation and product development both in academia and industries. Similarly, several statistical tools are being employed in the textile industry for process optimisation during the manufacturing of different products. The purpose of this study was to analyse different Taguchi-based techniques in the multi-response optimisation of selected industrial processes and then to generalise the outcomes. Herein, six different Taguchi-based multi-response optimisation techniques, including grey relational analysis (GRA), the weighted signal-to-noise (WSN) ratio, principal component analysis, VIKOR (VlseKriterijumska Optimizacija I Kompromisno Resenje), the multiple response signal-to-noise ratio, and Fuzzy logic were compared against three data sets of industrial processes. The researchers herein optimised cotton dyeing, the finishing of textile to make them oleo-hydrophobic, and the production of rhamnolipids (bio-surfactants). The results demonstrated that the Fuzzy logic-based Taguchi method gave the best optimisation amongst all the other approaches, followed by GRA and WSN for all the selected processes. The said statistical techniques were applied to specific textile and biotechnological processes. The outcomes of this study can help researchers in practical implementation in industrial sectors. In this study, a comparative analysis of the performances of six Taguchi-based multi-response optimisation techniques was conducted for potential industrial processes, particularly textile processing.
PL
Niegarbowane odpady skórzane pochodzące z przemysłu garbarskiego są potencjalnym zagrożeniem dla środowiska naturalnego. Z drugiej jednak strony tego rodzaju odpady zawierają znaczące ilości cennego białka – kolagenu. Białko kolagenowe jest biopolimerem, który z uwagi na swoje właściwości znajduje zastosowanie w przemyśle spożywczym, kosmetycznym oraz w przemyśle biomedycznym. Obecnie na rynku dostępne są preparaty kolagenowe pozyskane z odpadów pochodzenia zwierzęcego. W pracy przedstawiono procedurę oznaczania aminokwasów w wybranych preparatach kolagenowych metodą wysokosprawnej chromatografii cieczowej i metodą spektrofotometryczną. We wszystkich próbkach oznaczono wysokie stężenia glicyny, alaniny, proliny i hydroksyproliny, a niewielkie ilości tyrozyny, seryny, waliny i izoleucyny. Zastosowana metoda chromatograficzna umożliwia szybkie i równoczesne oznaczenie 17 aminokwasów w badanych próbach. Opracowane w ramach pracy metody analityczne mogą być wykorzystane m.in. do szybkiej kontroli składu aminokwasowego kolagenu.
EN
This work attempts to use nitrogen gas as a shielding gas at the cutting zone, as well as for cooling purposes while machining stainless steel 304 (SS304) grade by Computer Numerical Control (CNC) lathe. The major influencing parameters of speed, feed and depth of cut were selected for experimentation with three levels each. Totally 27 experiments were conducted for dry cutting and N2 gaseous conditions. The major influencing parameters are optimized using Taguchi and Firefly Algorithm (FA). The improvement in obtaining better surface roughness and Material Removal Rate (MRR) is significant and the confirmation results revealed that the deviation of the experimental results from the empirical model is found to be within 5%. A significant improvement of reduction of the specific cutting energy by 2.57% on average was achieved due to the reduction of friction at the cutting zone by nitrogen gas in CNC turning of SS 304 alloy.
EN
The objective of the present study is to optimize multiple process parameters in turning for achieving minimum chip-tool interface temperature, surface roughness and specific cutting energy by using numerical models. The proposed optimization models are offline conventional methods, namely hybrid Taguchi-GRA-PCA and Taguchi integrated modified weighted TOPSIS. For evaluating the effects of input process parameters both models use ANOVA as a supplementary tool. Moreover, simple linear regression analysis has been performed for establishing mathematical relationship between input factors and responses. A total of eighteen experiments have been conducted in dry and cryogenic cooling conditions based on Taguchi L18 orthogonal array. The optimization results achieved by hybrid Taguchi-GRA-PCA and modified weighted TOPSIS manifest that turning at a cutting speed of 144 m/min and a feed rate of 0.16 mm/rev in cryogenic cooling condition optimizes the multi-responses concurrently. The prediction accuracy of the modified weighted TOPSIS method is found better than hybrid Taguchi-GRA-PCA using regression analysis.
EN
In this paper, a numerical and experimental investigation of geometrical parameters of the blade for plastic bottle shredder was performed based on the Taguchi method in combination with a response surface method (RSM). Nowadays, plastic waste has become a major threat to the environment. Shredding, in which plastic waste is shredded into small bits, ready for transportation and further processing, is a crucial step in plastic recycling. Although many studies on plastic shredders were performed, there was still a need for more researches on the optimization of shredder blades. Hence, a numerical analysis was carried out to study the influences of the relevant geometrical parameters. Next, a two-step optimization process combining the Taguchi method and the RSM was utilized to define optimal parameters. The simulation results clearly confirmed that the current technique can triumph over the limitation of the Taguchi method, originated from a discrete optimization nature. The optimal blade was then fabricated and experimented, showing lower wear via measurement by an ICamScope® microscope. Hence, it can be clearly inferred from this investigation that the current optimization method is a simple, sufficient tool to be applied in such a traditional process without using any complicated algorithms or expensive software.
EN
High-quality products include those with better surface quality and texture, close dimensional tolerances and form accuracies at precise level, increase fatigue life and burr-free. Burr formation is one of the most common inevitable facts occurring in all material removal processes, reduces assembly and machined part quality. But, burr formation during milling is a more complex mechanism compare to remaining machining burrs and leads to numerous difficulties during the deburring process. To prevent this, one should optimize the combination of cutting parameters during machining itself. In order to build up a link between quality and productivity and to attain the same in the cost-effective way, the present work concentrate on multi objective optimization of CNC end milling process parameters. Multiple performance characteristics with respect to surface quality and performance index like assembly work have been put up, to assess an equivalent single quality index (called grey relational grade) has been optimized finally by Grey based Taguchi method. After that priority weight of individual quality and performance attributes has been estimated by entropy measurement technique on the basis of relative significance and check the feasibility of the proposed technique has been demonstrated in this context.
EN
Industries related to the acquiring of building materials may soon face a shortage of natural resources and an associated increase in costs of their acquisition. Therefore, it is necessary to look for possible ways to reduce the exploitation of natural resources and instead use recycled raw materials. Such policies fit into one of the most important trends in modern construction, which is sustainable development. In the conducted research, the Taguchi method was utilized in order to investigate the impact of modifying cement mortars with rubber and cork waste on the selected properties of the obtained composites. Thanks to the above method, we managed to obtain the desired information about mortars in a shorter time and at a lower cost than using traditional testing methods. Using the selection in planning method, we confirmed that rubber waste can be a good substitute for sand in mortars.
EN
In this paper we aim to improve the understanding of the relationship between unilateral-uniplanar external fixator design parameters and their influences on fixator performance. Stability and strength of bone-fixator construct as well as the quality of healing were defined as our major concerns in order to evaluate the performance of fixator. The roles of six key design parameters were assessed during the early stage of healing by using finite element models. Tissue differentiation within the callus was predicted through the implementation of a mechanoregulation theory of bone healing. Taguchi and ANOVA methods were used to achieve optimal design sets for outputs and to determine contribution percentage of each design parameter on outputs. For improving overall fixator performance, optimal set of design parameters consisting of 2 mm, 8 mm, 120 mm, 20 GPa, 50 mm and 20 mm were determined by Taguchi for pin diameter, rod diameter, rod elevation, fixator Young's modulus, distance of the nearest pin to fracture site and distance between adjacent pins, respectively. Also, results of ANOVA revealed that rod elevation is the most important design parameter, with 43 % effectiveness on overall fixator performance, which was followed by fixator material and pin diameter with 28 % and 19 %, respectively. Results of this study can assist orthopedic surgeons to achieve an optimal fixator device with respect to the patient's condition and give insight into the importance of different design parameters.
EN
Resistance spot welding (RSW) is a fabrication process that is being used in the automobile and aerospace industry since many years for joining low carbon or “mild” steel. Quality and strength of the welds depend upon the process parameters of RSW. The most effective parameters in this process are: current intensity, welding time, sheet thickness and material, geometry of electrodes, electrode force, and current shunting. This paper presents the experimental investigations for the optimization of tensile shear stress of RSW for stainless steel grade 316L sheets by using Taguchi method. The experiments were conducted using Taguchi’s L27 orthogonal array under varying proces parameters, namely electrode diameter, welding current, and heating time. The experimental data were analyzed using signal-to-noise ratio (S/N ratio) to find the optimal process parameters. Analysis of variance (ANOVA) and F test were used to find the most significant parameters affecting the spot weld quality characteristics. Confirmation tests with optimal process parameters were conducted to validate the test results. From the results, itwas found that it is possible to increase tensile shear stress significantly.
EN
Variation in final casting dimensions is a major challenge in the investment casting industry. Additional correction operations such as die tool reworking as well as coining operations affect foundry productivity significantly. In this paper influence of basic parameters such as wax material, mould material, number of ceramic coats and feed location on the dimensional accuracy of stainless-steel casting has been investigated. Two levels of each factor were chosen for experimental study. Taguchi approach has been used to design the experiment and to identify the optimal condition of each parameter for reduced dimensional deviation. Analysis of variance has been carried out to determine the contribution of each process parameter. The result reports that selected parameters have significant effect on the dimensional variability of investment casting. Mould material is the dominant parameter with the largest contribution followed by number of ceramic coats and wax material whereas feed location is having negligible contribution.
EN
Pre-structuring of magnetic particles during fabrication of magnetorheological elastomer (MRE) is a crucial step, which results in the formation of chain-like columnar structures in the rubber matrix. In this study, MRE based on natural rubber and carbonyl iron particles were prepared. The Taguchi method was utilized to study the effect of several dominating factors during the fabrication process such as pre-curing time, pre-curing temperature and applied magnetic field during curing on the loss tangent (tan δ) and tensile properties. Tan δ was measured through parallel-plate rheometer over a frequency range of 1–100 Hz and a strain amplitude range of 0.1–6%. Tensile properties were measured with a universal tensile testing machine. The obtained data were statistically analyzed using S/N ratios and ANOVA in order to predict the optimal combination of factors, and then further experiments were conducted for verification purpose. Results indicated that the magnetic field had the greatest influence on tan δ when measured over a range of frequency and elongation at break. Furthermore, pre-curing time and magnetic field were found to influence tan δ when measured over a range of strain amplitude. However, none of the factors exhibited significant influence on tensile strength. In addition, the morphology of MRE was examined using scanning electron microscopy (SEM).
PL
Dynamiczny rozwój przemysłu motoryzacyjnego dotknął również pojazdy wykorzystywane w pracach polowych. Poruszają się one z coraz to większymi prędkościami, charakteryzują się też większymi masami. Ich zatrzymanie wymaga więc stosowania nowych, bardziej wydajnych hamulców. To z kolei wymusza prowadzenie licznych badań mających na celu optymalizację składu okładzin ciernych. Do badań wykorzystuje się różne metody. Najkorzystniej jest, jeżeli wykonuje się badania na obiekcie rzeczywistym. Jednak mało kiedy jest to możliwe. W badaniach laboratoryjnych próbuje się jak najlepiej odzwierciedlić obiekt badań, jednak stanowiska badawcze zapewniają jedynie pewne przybliżenie. Wielu naukowców zajmuje się obecnie badaniami symulacyjnymi. Ich główną zaletą jest niski koszt oraz praktycznie nieograniczona możliwość wariacji warunków badań. Niniejsza praca ma na celu zaproponowanie nowej metody badawczej wykorzystującej kontakt Ball-Cratering. Do odpowiedniego zaplanowania eksperymentu zaproponowano metodę optymalizacji procesów Taguchi. W celu zweryfikowania prawidłowości proponowanej metody wykonano przykładowe badania. Wyznaczono w nich wartości współczynnika tarcia oraz współczynnika szybkości zużywania ściernego.
EN
The dynamic development of the automotive industry also affected vehicles used in agricultural. They are running at higher speeds, they are also characterized by larger masses. Their stopping therefore requires the use of new, more efficient brakes. This, in turn, requires numerous studies to optimize the composition of friction materials. Various methods are used for research. It is most beneficial if tests are carried out on a real object. However, not often it is possible. Laboratory tests attempt to reflect the research object as closely as possible, but the test stands provide only some approximation. Many researchers are currently involved in simulation research. Their main advantage is lower cost and virtually unlimited variation of test conditions. This work aims to propose a new research method using Ball-Cratering contact. The method of Taguchi optimizing processes was proposed for the appropriate planning of the experiment. In order to verify the correctness of the proposed method, examinations were carried out. As a result, the values of the coefficient of friction and the coefficient of abrasive wear rate were determined.
15
Content available remote Rotary smart car parking system
EN
Problems with parking individual cars, particularly in urban areas, were already experienced by the inhabitants of developed countries in the interwar period. These problems continue to appear, as the number of cars increases and there are fewer and fewer parking spaces. Therefore, solutions are sought after to ensure the largest possible number of parking spaces with the smallest occupied area, especially in large agglomerations of highly developed countries. The article presents one of the possible solutions – rotary car parks (The Rotary Automated Car Parking System; RACPS). The research results reffered to in the article are the effect of works conducted at the Faculty of Mechanical Engineering of the Cracow University of Technology in the field of modelling and optimisation of a rotary car park [5, 6, 8].
PL
Kłopoty z parkowaniem samochodów indywidualnych szczególnie w obszarach miejskich mieli już w okresie międzywojennym mieszkańcy krajach rozwiniętych. I te problemy w dalszym ciągu się pojawiają, ponieważ ilość samochodów wzrasta, a miejsc do parkowania mamy coraz mniej. Dlatego poszukuje się rozwiązań, które mają zapewnić jak największą liczbę stanowisk parkingowych przy jak najmniejszej powierzchni zajmowanej, szczególnie w wielkich aglomeracjach krajów wysokorozwiniętych. W artykule przedstawiono jedno z możliwych rozwiązań, jakim są parkingi obrotowe (The Rotary Automated Car Parking System; RACPS). Wyniki badań przytoczone w artykule są efektem prowadzonych na Wydziale Mechanicznym Politechnice Krakowskiej prac z zakresu modelowania i optymalizacji obrotowego parkingu samochodowego [5, 6, 8].
EN
Since G.E.P. Box introduced central composite designs in early fifties of 20th century, the classic design of experiments (DoE) utilizes response surface models (RSM), however usually limited to the simple form of low-degree polynomials. In the case of small size datasets, the conformity with the normal distribution has very weak reliability and it leads to very uncertain assessment of a parameter statistical significance. The bootstrap approach appears to be better solution than – theoretically proved but only asymptotically equal – t distribution based evaluation. The authors presents the comparison of the RSM model evaluated by a classic method and bootstrap approach.
EN
The design of experiment (DoE) is a methodology originated from early 1920s when Fisher’s papers created the analysis of variance and first known experimental designs: latin squares. It is focused on a construction of empirical models based on measurements obtained from specifically structured and driven experiments. Its development resulted in the constitution of four distinctive branches recognized by the industry: factorials (full or fractional), Taguchi’s robust design, Shainin’s Red-X® and a response surface methodology (RSM). On one hand, the well-known success stories of this methodology implementations promise great benefits, while on other hand, the mathematical complexity of mathematical and statistical assumptions very often lead to improper use and wrong inferences. The possible solution to avoid such mistakes is the expert system supporting the design of experiments and subsequently the analysis of obtained data. The authors propose the outline of such system and provides the general analysis of the ontology and related inference rules.
EN
Friction Stir Welding (FSW) was carried out on Aluminum Alloy 6082-T6 plates with dimensions of 200 x 70 x 2 mm. Design of Experiment (DOE) was applied to determine the most important factors which influence the Ultimate Tensile Strength (UTS) and Hardness (HV) of AA 6082-T6 joints produced by Friction Stir Welding (FSW). Effect of two factors which include tool rotational speed and welding speed on (UTS, HV) were investigated by Taguchi method using L9 orthogonal array to find the optimum process parameters. An analysis of variance (ANOVA) was carried out to determine which of the selected factors are more significant on both of responses, the optimum parameters for the higher UTS it found by using a rotational speed of 1400 rpm and 125 mm/min for the welding speed, also 1400 rpm and 160 mm/min to maximize Hardness (HV).
EN
The utilization of TiB2 particles reinforced aluminum (Al6063) metal matrix composite materials in many different engineering fields has undergone a tremendous increase. Accordingly, the need of accurate machining of composites has increased enormously; an attempt has been made to assess the factors influencing surface roughness and material removal rate on machining the composite. The orthogonal array, the signal-to-noise ratio, and analysis of variance were employed to study the performance characteristics in turning operations of 5 and 10 wt. % TiB2 particles reinforced aluminum (Al6063) metal matrix composites. Taguchi method was used to find the optimal cutting factors for surface roughness (Ra) and material removal rate (MRR). Three cutting factors namely speed; feed and depth of cut were optimized with considerations of Ra and MRR. The experimental plan and analysis was based on the Taguchi L27 orthogonal array with three cutting factors using carbide tool (K20). The optimal parametric combination for K20 carbide insert was found to be feed, speed and depth of cut. The analysis of variance (ANOVA) result shows that feed the most significant process parameter on surface roughness followed by speed. For MRR result show that the speed and the feed are the significant parameters followed by the composition of composite material.
EN
Owing to the distinguished properties Metal Matrix Graphite Hybrid Composites (Al/SiCMMC-Gr) are used in various applications. This paper deals with the utility of Taguchi and response surface methodologies for the prediction of surface roughness in tuning of these materials with PCD tool. The cutting parameters effect on surface quality is analyzed and an empirical model with respect to turning parameters is established using response surface method. The most important parameter that influences the turning Al/SiC-MMC-Gr is feed. The measured and predicted results are approximately equal, which proves that, model is to be used for predicting surface finish in turning of these composites. Validation experiments have been used to confirm the predicted results.
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