Taguchi Experiment Research Articles

Optimisation of laser welding parameters to maximise the joint strength of laser weld stainless steel joints using a GA for geothermal plants

ABSTRACTLaser beam welding is vital in high-temperature fields such as the aerospace, automobile, and gas turbine manufacturing industries. In this article, parametric studies are carried out on Nd:YAG laser weldments that influence stainless steel 430 L weldment quality. A series of trial runs are organised to investigate input parameters such as peak power, frequency, speed, and time that impact output responses such as yield strength, ultimate tensile strength, shear strength, and elongation simultaneously. Trail runs on martensitic stainless steel AISI 430 L are conducted based on Taguchi experiments, and a regression equation is established. To yield optimum results, the process parameters are optimised by using the genetic algorithm optimisation technique. By conducting experimentation with optimum parameters, the output responses are compared with the optimum results 95% confidence level was obtained. The optimum levels for process variables are identified for quality weld peak power 160 kW, frequency 9 Hz, speed 3.33 mm/ms, and time 2.53 ms. Optical microscopy reveals that refined grains are formed in the weld zone with a grain size of 2.909 µm, and a scanning electron microscopy test is performed to study the morphology of AISI 430 L weldment specimen failure takes place at the interface of the weld metal.

Variability of internal standard method calibration factors estimated with a multifactorial Taguchi experiment in the analysis of alcoholic products by gas chromatography with flame ionization detection.

This study compares the variability of relative response factors (RRFs) using Taguchi's multifactorial analysis for two internal standard (IS) methods in gas chromatography (GC) for quality control of alcoholic products. Methods where either ethanol or pentan-1-ol was used as an IS were compared. For ten volatile substances prescribed by legislation, the RRFs of both methods were compared under 27 different experimental conditions. The influence of parameters (control factors) such as ethanol content in the matrix, analyte concentration, injected volume, injector temperature, split ratio, and flame ionization detector temperature was evaluated. The selected control factors had values at one of the three levels to cover the commonly used ranges of their settings in the measuring system and to characterize the majority of alcoholic products commonly analyzed in practice. The obtained results showed that the biggest differences in the variability of the results between the two methods were found for the most strictly controlled substances in alcoholic products, acetaldehyde, and methanol, where the application of ethanol as an IS provides clearly better results. For both methods, the way control factors affect the repeatability of GC measurements expressed in the form of relative deviation was also evaluated.

Taguchi method-based evaluation of thermal hazard of lift-off pyrotechnics under various storage conditions

This study employed the Taguchi method and analysis of variance to investigate the factors that influence the deterioration of the lift-off pyrotechnics when they are stored under various relative humidity (RH) and temperature conditions. A field emission scanning electron microscope and an energy-dispersive X-ray spectroscope were used to observe the microstructures and elements of pyrotechnic samples. Differential scanning calorimetry (DSC) and Vent Sizing Package 2 (VSP2) were applied to measure the relationship between the trace heat flow of the samples and temperature as well as the thermal runaway reactions in a pseudo-adiabatic environment. A DSC analysis and a thermodynamic ASTM E698 analysis were combined to explore the safety of lift-off pyrotechnics and the related thermal hazards.The energy-dispersive X-ray spectroscopy and DSC experimental results revealed that KNO3 is highly soluble. However, when RH and exposure time increased, the surface dissolution of oxidants decreased the height of the second exothermic peak, resulting in incomplete combustion and ignition failure. The ASTM E698 thermokinetic analysis results indicated that the apparent activation energy (Ea) of the samples increased substantially after being immersed in deionized water. Notably, the Ea of colored smoke increased from 46.88 to 155.91 kJ/mol, indicating that the examined pyrotechnics were more sensitive to a decrease in temperature than to an increase in humidity. A large amount of water can be used to alleviate the reactivity of pyrotechnics and thus reduce pyrotechnic hazards. The VSP2 analysis results indicated that the self-boosting rate of the samples was greater under 40% RH than under pristine conditions; however, this rate decreased substantially under 80% RH and after immersion in deionized water. The results of the Taguchi experiment and analysis of variance revealed that humidity contributed 63.60% and 50.86% to Ea and maximum pressure, respectively. Accordingly, controlling humidity should be prioritized to diminish the hazard of storing pyrotechnics.

Location decision of low-altitude service station for transfer flight based on modified immune algorithm

The location of Low-Altitude Flight Service Station (LAFSS) is a comprehensive decision work, and it is also a multi-objective optimization problem (MOOP) with constraints. As a swarm intelligence search algorithm for solving constrained MOOP, the Immune Algorithm (IA) retains the excellent characteristics of genetic algorithm. Using some characteristic information or knowledge of the problem selectively and purposefully, the degradation phenomenon in the optimization process can be suppressed and the global optimum can be achieved. However, due to the large range involved in the low-altitude transition flight, the geographical characteristics, economic level and service requirements among the candidate stations in the corridor are quite different, and the operational safety and service efficiency are interrelated and conflict with each other. And all objectives cannot be optimal. Therefore, this article proposes a Modified Immune Algorithm (MIA) with two-layer response to solve the constrained multi-objective location mathematical model of LAFSS. The first layer uses the demand track as the cell membrane positioning pattern recognition service response distance to trigger the innate immunity to achieve the basic requirements of security service coverage. In the second layer, the expansion and upgrading of adjacent candidate sites are compared to the pathogen’s effector, and the adaptive immunity is directly or indirectly triggered again through the cloning, mutation and reproduction between candidate sites to realize the multi-objective equilibrium of the scheme. Taking 486,000 km2 of Sichuan Province as an example, MIA for LAFSS is simulated by the MATLAB platform. Based on the Spring open source application framework of Java platform, the cesiumjs map data is called through easyui, and the visualization of site selection scheme is presented with the terrain data of Map World as the background. The experimental results show that, compared with dynamic programming and ordinary immunization, the immune trigger mode of double response and the improved algorithm of operation parameter combination designed by the Taguchi experiment, the total economic cost of location selection is reduced by 26.4%, the service response time is reduced by 25%, the repeat coverage rate is reduced by 29.5% and the effective service area is increased by 17.5%. The security risk, service efficiency and location cost are balanced. The present work is to provide an effective location method for the layout number and location of local transfer flight service stations. For complex scenes with larger scale of low-altitude flight supply and demand and larger terrain changes in the region, the above research methods can be used to effectively split and reduce the dimension.

Microstructure evolution and tensile strength of Al/Cu inertia friction welded joint

To save production costs and reduce the weight of structures, it is one of the common ways to replace copper (Cu) with aluminum (Al) in some industries such as the refrigeration industry. The high-quality welding of Al to Cu determines the application of the Al/Cu hybrid structure. The inertia friction welding process was used to weld Al pipe to Cu pipe and the Taguchi experiment method was used to study the effects of inertia friction welding parameters on the mechanical properties of the welded joints, and the results show that the initial speed has the greatest influence on the tensile strength of welded joints. Meanwhile, the analyses of the microstructures of the joint show that Al–Cu IMCs formed at the friction interface to realize the metallurgical bonding of the welded joints. The formation sequence of Al–Cu IMCs in the friction welding process is Al2Cu, Al4Cu9, and AlCu. Whereas the type and thickness of IMCs are closely related to the tensile strength of the joints. When the welded joint forms Al2Cu and Al4Cu9, the interfacial misfit between the IMCs layer and base materials is minimized and the tensile strength of the joint is optimized.

Study on the application of 3D printing to wooden furniture connectors

With the rapid development of high technology in the 21st century, the manufacturing industry cannot be exempted from it. In addition, 3D printing is a multi-layer manufacturing technology that has emerged in recent years, and it is gradually integrated into the manufacturing process of components in various industries, such as aerospace, medical, military, transportation and construction industries. However, the use of 3D printing to make wooden furniture connectors has gradually replaced the traditional way of connecting wooden furniture. Like other 3D printed products, the size of the connectors of 3D printed wooden furniture is also affected by its molding accuracy. In order to obtain the best precision 3D printed wooden furniture connectors, the experimental parameters of this study are designed by Taguchi experiment method, and the measurement is carried out by 3D scanner equipment. The research results show that when the experimental parameters are the nozzle temperature of 200 °C, the layer thickness of 0.1 mm, the filling degree of 20 %, and the extrusion speed of 50 mm/s outside and 100 mm/s inside, the printed 3D wooden furniture connectors have the best accuracy.

Experimental and statistical investigation on structural feasibility of admixture based foam concrete with hexagonal wire mesh reinforcement

Foam concrete is an emerging construction material with reduced self-weight, high workability and improved thermal resistance. Deployment of this foam concrete for structural applications has not drawn keen attention of the research community. This study reports an investigation on the viability of using admixtures like, crumb rubber, silica fume and polypropylene fiber in foam concrete, reinforced with hexagonal wire mesh for enhanced strength and energy absorption. Taguchi's experiment design methodology was applied for assessment of the optimal mix of foam concrete with admixtures. Mixtures with three factors, namely silica fume, polypropylene fiber (PP fiber), and crumb rubber were developed in an L9 orthogonal array. Compressive and flexural strength parameters were used to establish the best possible mix proportions for maximum strength. Tests were conducted on hexagonal wire mesh (chicken mesh) kept in horizontal, vertical and horizontal with stirrup arrangements and the results were compared with control mix and the selected optimized mix. In all cases, percentage of steel reinforcement for the total volume of the concrete was kept as 1% by adjusting the layers of mesh provided. Based on the experimental results, crack and deflection patterns were analyzed and compared with the control specimen. The test results demonstrated enhanced strength and ductility of the foam concrete, buttressed by hexagonal wire steel mesh, as compared to control specimens. Besides, the reinforcement in the horizontal alignment with admixtures provided better strength and ductility with an enhancement of 130 % in flexural strength and a ductility index of 3.88 compared to control. Prognosis of the study advocated the propriety of using foam concrete as a structural member in construction.

Investigation of Sheet Thickness and Punch Force in Die Surface Angled Hydro-mechanical Deep Drawing Method

In this study, the effect of die surface angled hydro-mechanical deep drawing method (HMDDM) on sheet metal cup wall thickness and punch force was investigated as experimental and numerical analysis. In the works, 0.9 mm thick DIN EN 10130-1999 sheet metal material was used. The effect of variables on the test results was investigated by using die surface/blank holder angle, punch nose radius, die shoulder radius, chamber pressure and blank holder force as experimental parameters. Numerical analysis experiments were carried out using ANSYS 15.0 package program. Besides, experiments were performed according to the Taguchi experiment plan and L18 orthogonal array. The obtained data were analysed statistically by ANOVA analysis of variance in MINITAB 17.0 package program, and the effect of each parameter on the results was determined as a percentage. As a result, it was determined that the thinning was approximately 15% at most and the thickening was 10%.

Tribological Performance Evaluation of TMPTO Based Nano-Lubricants

In recent years, nano lubricants have gained significant attention due to their potential to enhance lubricant efficacy and reduce friction and wear. This research work aims to investigate the effects of TiO2 nanoparticles into trimethylolpropane trioleate (TMPTO) based bio-lubricant on its friction and wear characteristics. The four-ball tester is employed to evaluate the lubricating performance of the TMPTO-TiO2 nano-lubricant at varying additive concentrations under controlled conditions of speed, load, and temperature. The parameters were ranked based on the results of the Taguchi experiments and their corresponding single-to-noise ratios. The combination of TMPTO base oil and TiO2 nano-lubricant exhibited a synergistic effect in diminishing friction and wear. This research aligns with the growing demand for environmentally friendly and efficient lubrication solutions in various metalworking industries. Further investigation of the wear mechanism under TMPTO oil-based nano lubricants and its applicability in high-speed metal cutting applications is suggested.

ANOVA Analysis and L9 Taguchi Design for Examination of Flat Slide Burnishing of Unalloyed Structural Carbon Steel

Diamond burnishing is a finishing precision machining that is often used to improve the quality characteristics of previously machined surfaces. With its help, the surface roughness can be reduced, the surface hardness can be increased, and the tensile stresses remaining in the surface after cutting can be transformed into compressive ones, and these changes can increase the service life of the components. Diamond burnishing was typically developed for processing cylindrical surfaces and is most often used for this type of surface. In this manuscript, we present a new method with the help of sliding burnishing, which can also be used on flat surfaces. By using the clamping head of a special tool into the main spindle of the vertical milling machine and moving it along a suitable path, the flat surface can be burnished. Machining experiments were carried out with the new type of tool on general-purpose, unalloyed, structural carbon steel samples on which the flat surfaces were previously generated by face milling. The examined parameters were the burnishing force F, the feed fb, and the number of passes (NoP). The L9 Taguchi experiment design was applied for executing flat slide burnishing, and the examination was conducted by ANOVA analysis. This research contributes to the field by providing insights into optimizing the burnishing process parameters for achieving desired surface quality in milling operations.

Using Taguchi's experiments part II: creating a computer for heavy games and image processing

This study aimed to identify and present applications of statistical methods in problems of agricultural and environmental nature. To achieve this objective, an applied research of exploratory and quantitative nature was carried out. Two case studies were adopted as method and technical procedures. As a contribution to this research, the use of statistical methods in problem solving and as a tool for decision making is pointed out.

Investigation of Performance Properties of Dyed and Raised Twill Woven PES/VIS Fabrics by Full Factorial and Taguchi Experiment Design Methods

In this study, full factorial experimental design and Taguchi experimental design for the optimization of selected fabric quality parameters were examined comparatively with an experimental study. The aim of the study is to show that Taguchi Experimental Design can be used instead of Full Factorial Experimental Design, which is a classical experiment plan in textile engineering studies. In the experimental study developed in outerwear woven fabric dyeing-finishing enterprises; The woven fabric in three different twill forms, having the same blend, was dyed at three different rates and produced in three different raising conditions. The fabrics were woven 100 m in factory conditions and dyed and raised under the same conditions. The selected twill texture is 3/1, 2/1, 2/2, dyeing ratio, 1%, 3%, 5% and raising status-no raising, single passage raising, two passage raising (shearing process is included in all raising). Selected woven fabric performance tests were applied to the fabrics. In the study, 27 fabric samples were used for the Full Factorial Experiment Design and 9 fabric samples were used according to the Taguchi Experiment Design. The results of the performance tests obtained according to both experimental designs were compared. As a result, it has been shown with this study that 9 samples according to the Taguchi method can be used instead of 27 samples according to the full factorial experimental design for optimum results. Experimental design based on Taguchi Method can be used effectively with less experiments in experimental studies where production is very difficult and costly in the field of textile engineering.

Using Taguchi's experiments part i: creating a golf ball that reaches a maximum range

This study aimed to identify and present applications of Taguchi's experimental methods for golf ball production. To achieve this objective, applied research of exploratory and quantitative nature was conducted. A case study was adopted as method and technical procedures. As a contribution of this research, the use of Taguchi's experimental methods in problem solving and as a tool for decision making is pointed out.

Advanced Treatment of Coking Wastewater by Polyaluminum Silicate Sulfate for Organic Compounds Removal.

Coking wastewater is a typical high-strength organic wastewater, for which it is difficult to meet discharging standards with a single biological treatment. In this study, effective advanced treatment of coking wastewater was achieved by coagulation with freshly prepared polyaluminum silicate sulfate (PASS). The performance advantage was determined through comparison with commercial coagulants including ferric chloride, polyferric sulfate, aluminum sulfate and polyaluminum chloride. Both single-factor and Taguchi experiments were conducted to determine the optimal conditions for coagulation with CODCr and UV254 as indicators. A dosage of 7 mmol/L PASS, flocculation velocity of 75 r/min, flocculation time of 30 min, pH of 7, and temperature of 20 °C could decrease the CODCr concentration from 196.67 mg/L to 59.94 mg/L. Enhanced coagulation could further help to remove the organic compounds, including pre-oxidation with ozonation, adsorption with activated carbon, assistant coagulation with polyacrylamide and secondary coagulation. UV spectrum scanning and gas chromatography-mass spectrometry revealed that the coagulation process effectively removed the majority of organic compounds, especially the high molecular weight alkanes and heterocyclic compounds. Coagulation with PASS provides an effective alternative for the advanced treatment of coking wastewater.

Experimental Evaluation of Stiffness Properties of a Quicklime-Stabilized Clay Subgrade Using a Resistivity Plate Loading Testing Device

Quicklime-mixing in soil stabilization applications for subgrade construction is crucial to its engineering performance and controlling quicklime and water content. Modern construction quality control devices and methods have improved construction quality control substantially. Certain devices, meanwhile, still need to be studied more thoroughly. This study used the resistivity plate loading device to assess the physical and stiffness properties of compacted quicklime-stabilized subgrade instantaneously and simultaneously for compaction quality control. The Taguchi L9 orthogonal array was used to design the experiment considering the dry density, test time, quicklime, and water content at various input factor levels. The pH, cation exchange capacity, conductivity, X-ray diffraction analysis (XRD), and scanning electron microscope (SEM) tests were further conducted. Analysis of the Taguchi experiment shows that the average soil electrical resistivity responses increased with dry density, test time, and quicklime content, and were highest at low water content. Whether the dry density, quicklime content, and test time are positively or negatively related to the average subgrade reaction modulus depends on the level of the water content. Regression equations are proposed to predict the average subgrade reaction modulus and soil electrical resistivity. The tested soils’ pH, conductivity, and cation ion exchange capacity properties were directly related to the test time, water, and quicklime content. The XRD showed nearly similar X-ray diffraction peaks. The SEM analysis confirmed marked changes in the microstructure of the samples that explained the changes in electrical resistivity and subgrade reaction modulus responses. The test results show that the resistivity plate loading device efficiently assesses compacted quicklime’s stiffness and physical properties at ease and instantaneously.

Optimization of hybrid pulse power characterization profile for equivalent circuit model parameter identification of Li-ion battery based on Taguchi method

The modeling of Li-ion batteries is crucial for their stable and efficient operation. The equivalent circuit model (ECM) is the most widely used battery model, for which parameter identification usually involves the hybrid pulse power characteristic (HPPC) test. However, since the HPPC test was designed to determine dynamic power capability of batteries, an investigation of how HPPC parameters affect ECM parameter identification would be reasonable. In this study, the Taguchi method was employed to investigate the effect of four HPPC parameters (positive and negative pulse height, length of pulse and length of relaxation) on ECM's performance under various application conditions (dynamic test, non-dynamic test and quasi-static test). The results show that all four parameters have an effect on ECM performance. For batteries operated only with the predictable charge and discharge patterns, the optimal combination of HPPC parameters values was determined based on Taguchi experiments. If batteries face unpredictable application scenarios, lower positive pulse heights, higher negative pulse heights, shorter pulse lengths and longer relaxation lengths within a certain range should be considered. Compared to established standard parameter values, this makes it possible to build a more accurate general model.

Optimal design and performance analysis of Rotating Power Flow Controller

In this paper, a scheme of rotating power flow controller (RPFC) is proposed, which can flexibly and effectively reduce the voltage deviation under the disturbance of distributed generation and load side. Firstly, based on the prototype of a new rotating power flow controller (RPFC) with a rated capacity of 40 kVA, a two-dimensional finite element model based on the core component RPST is established. Then the optimal parameter combination in RPST is determined by the Taguchi experiment method and weight calculation. Finally, Matlab, Maxwell, and Simplorer are used to realize the joint simulation of field-circuit coupling. The results show that the voltage regulation efficiency and power factors of RPFC are increased by 1.4% and 2.7% respectively under the optimal parameter combination, which provides a reference for the design and engineering application of large-capacity RPFC.

A Model Experiment Design Using the Taguchi Method: A Case Study Of Making Concrete Roof

This research was conducted at a company manufacturing paving blocks, ceramics, ventilation, concrete, and roof tiles. This study aims to improve the quality of concrete tile products, which experience the most cracks and breaks. Research to determine the composition of concrete roof tiles can be carried out by design experiments using the Taguchi method. This experiment used raw materials such as cement, sand, milled flour, and water. The concluding results show that the quality of concrete roof tiles is based on the results of the Taguchi method and confirmation experiments which are characterized by an increase in the compressive strength of the concrete tile based on the average value (μ) and its variability (SNR). The average compressive strength (µ) of concrete roof tiles increased from 19,814 ≤ 21,208 ≤ 22,602 in the Taguchi experiment to 26,406 ≤ µconfirmation ≤ 29,894 in the confirmation experiment. While the variability (SNR) increased from 25.532 ≤ 27.521 ≤ 29.510 in the Taguchi experiment to 26.473 ≤ S/N confirmed ≤ 31.469 in the confirmation experiment. The optimal composition of cement, sand, milled flour, and water that produces the best compressive strength based on the response factor and SNR is 0.9 kg: 0.5 kg: 0.4 kg: 0.3 kg, respectively. The most influential factors on the compressive strength of concrete roof tiles are the amount of sand and the number of flour mills.

Site-directed modification of multifunctional lignocellulose-degrading enzymes of straw based on homologous modeling.

Studying the straw lignocellulose strengthening mechanism during simultaneous degradation has important practical significance for improving resource utilization and reducing environmental pollution. In this paper, the degradation ability of four straw lignocellulose-degrading enzymes was evaluated by molecular docking and molecular dynamics. Using the significantly binds to straw lignocellulose-degrading enzyme as a template, a multifunctional lignocellulose-degrading enzyme 3CBH-1KS5-4XQD-1B85 was constructed based on amino acid recombination and homologous modeling. Five efficient degrading enzymes (3CBH-1, 3CBH-2, 3CBH-3, 3CBH-4, and 3CBH-5) were designed by site-directed mutagenesis of 3CBH-1KS5-4XQD-1B85 amino acid at position 346. Molecular dynamics showed that the degradation ability of 3CBH-1 was significant and it was 1.45 times higher than 3CBH-1KS5-4XQD-1B85. Moreover, the mechanism of enhanced degradability and the stability of the enzymes were explored. With the aid of Taguchi experiments, the suitable external environment for degrading straw was determined. In the presence of inhibitors (organic acids and phenolic compounds), the binding energy of 3CBH-1 (238.46 ± 30.96kJ/mol) is 36.42% higher than that of 3CBH-1KS5-4XQD-1B85 (174.79 ± 20.35kJ/mol) without external environmental stimulation. Based on homology modeling, this paper constructed a site-directed mutagenesis scheme of multifunctional enzymes, and the aim was to obtain multifunctional and efficient straw lignocellulose-degrading enzymes through protein engineering, which provided a feasible scheme for straw biodegradation.

Field measures of strengthen plant-microbial remediation of PAHs-FQs compound pollution.

In this study, five PAHs (benzo [b] fluoranthene (BbF), phenanthrene (Phe), fluoranthene (Flu), fluorene (Fl), benzo [A] pyrene (Bap)), and five FQs (ofloxacin (OFL), enrofloxacin (ENR), ciprofloxacin (CIP), norfloxacin (NOR), lomefloxacin (LOM)) were selected as ligands; peroxidase (1NML) was selected as receptor degrading protein. In the plant-microbial degradation, the factors with significant inhibitory effects are NOR, Bap, CIP, ENR, OFL, Flu, LOM, Phe, Fl, and BbF by the fractional factorial design experiment and molecular docking-assisted molecular dynamics methods. Using Taguchi experiment and molecular dynamics simulation methods, the main external field measures were designed and screened to effectively promote the degradation of PAHs-FQs under the combined pollution scenarios of Bap-CIP and BbF-NOR, respectively. The peroxidase mutation design plans with enhanced substrate affinity were then designed and screened using the DS software by predicting the virtual key amino acid of peroxidase. The novel biodegradable enzymes 2YCD-1, 2YCD-4, 2YCD-5, 2YCD-7, and 2YCD-9 had better structures and showed excellent degradability for PAHs and FQs. This study explored the degradation rules of the composite pollutants in the coexistence systems of multiple PAHs and FQs, providing the best external field measures for the control and treatment of the combined pollution effects of different PAHs and FQs. Overall, the current study has important practical significance for promoting the plant-microbial joint remediation of PAHs-FQs pollution and for reducing the combined pollution of PAHs and FQs in farmland systems.