Taguchi method

Introduction and Objectives: In this study, the microstructural and mechanical properties of dissimilar resistance spot welds between DP590 and HSLA440 steels were investigated, with a focus on the effect of welding current.
Materials and Methods: For this purpose, steel sheets were prepared in accordance with AWS D1.1 standard. Welding was performed using currents ranging from 7 to 11 kA (in 1 kA increments), followed by mechanical testing and characterization. Tensile shear tests were conducted at a crosshead speed of 1 mm/min, and hardness tests were carried out for the 8 and 10 kA welds. Furthermore, fracture surface and weld microstructure analyses were performed using optical and scanning electron microscopy.
Results: Weld nugget was mainly consisted of lath martensite; its volume fraction increased with current and decreased toward base metal. In DP590, the supercritical and intercritical regions were martensitic and the subcritical region was tempered. In HSLA440, the supercritical regions showed martensite, the intercritical regions showed a combination of martensite and ferrite, and the subcritical region showed grain growth.Tensile strength enhanced from 10.84 kN (for 7 kA) to 24.34 kN (for 10 kA). Fracture mode shifted from interfacial to pull-out above 9 kA. Hardness increased with current, peaking at 430 HV (10 kA).
Conclusion: An increase in welding current caused to increase in nugget size and peak load. Also, softening was more pronounced on the HSLA440 side. The sample welded at a current of 10 kA with a tensile failure mode and maximum strength, hardness, and elongation was the optimal sample.

This paper reviews the optimization of cutting parameters for surface roughness in the turning process. Surface roughness is one of the most commonly used criteria to determine quality of a turned surface. The surface roughness of a turned surface is an important response parameter. Surface roughness contributes to better function or longer life span. It also contributes to abrasion resistance material and good wear resistance. Taguchi method is a powerful tool to design optimization for quality. It is used to find the optimal cutting parameters such as cutting speed, feed rate, depth of cut and nose radius as the overall cost can be reduced. This paper gives some background of optimization technique applied to various turning processes for improving surface roughness.

The present investigation is undertaken with the intent to utilize Taguchi method of structured empirical approach with an L16 orthogonal array to optimize the strength and fresh concrete qualities by combining different ratios of steel slag and metakaolin. Concrete’s mechanical integrity can be considerably increased by adding mineral additions like fly ash and silica fume, according to earlier studies. In an effort to create cement formulations that are more sustainable, increased attention is being paid to using waste-derived materials and post-industrial outputs as reinforcing agents. To augment the overall engineering characteristics of concrete, metakaolin and steel slag are utilized in this work as partial substitutes for cement and M-sand, respectively. By using steel slag in place of fine aggregate and metakaolin in place of cement, the main objective is to forecast and improve the unique qualities of concrete. Cementitious material to water ratios (w/cm) at 0.36, 0.38, 0.40, and 0.42; metakaolin to cementitious material ratios (M/cm) at 10%, 15%, 20%, and 25%; and steel slag to fine aggregate ratios (SS/FA) at 10%, 20%, 30%, and 40%, are the control factors. After seven and twenty-eight days, the concrete's fresh and hardened qualities were assessed. Results demonstrate that metakaolin, when utilized as a cementitious substitute, contributes to a notable enhancement of up to 10% in the compressive strength at 28 days. Moreover, steel slag sand greatly increases split tensile strength at this level while making a little contribution to compressive strength up to 30% replacement. Comparing the outcomes with a control mix showed how these substitutions could enhance the performance of the concrete.

The commercially pure (CP) titanium cylindrical flat pins were subjected to wear on a standard pin-on-disc machine against a SiC abrasive disc for a dry sliding condition in the atmospheric air. The design of experiments (DOE) approach using Taguchi method was employed to predict the wear behavior against variable parameters such as load, speed and sliding duration. Also signal-to-noise ratio and analysis of variance (ANOVA) were used to study the influence of these parameters on the wear loss. It was observed that load has a significant effect on wear followed by speed and duration. A multiple linear regression equation has been developed and the error associated with confirmation test is 1.52% to 10.96%.

Paper Type: Research Paper The carcinogenicity and high toxicity of chromium (VI) show that the removal of this pollutant in industry, water resources, and the environment is necessary. Nanoporous materials have a high ability to remove pollutants. The aim of this study was to synthesize SBA-16 nanostructure using P123 and F127 surfactants and TEOS precursor and grafting its surface in two steps with-NH2 (NH2-SBA-16) and then with copper (Cu-NH2-SBA-16). Cu-NH2-SBA-16 was identified as a new adsorbent by XRD, SEM, EDX, and FT-IR analysis. The synthesis of nanoporous functionalized with amino group-NH2 was done by reflux and then grafting of prepared nanoporous with copper (II) solution was performed. The maximum adsorption capacity of NH2-SBA-16 and Cu-NH2-SBA-16 was 6.66 and 34.48 mg/g, respectively. In addition, the kinetics of chromium adsorption followed the pseudo-second-order kinetic model. The maximum efficiency of chromium removal by Cu-NH2-SBA-16 for contact time, initial concentration, amount of adsorbent, pH and temperature were 15 min, 10 mg/l, 1 g/l, 2, and 25 °C, respectively; adsorption capacity of Cu-NH2-SBA-16 increased after the modification process. The synthesized nanoadsorbent with an efficiency of 90% had a spontaneous and endothermic adsorption process, and its adsorption capacity did not decrease significantly after 3 regenerations.

Electrical discharge machining (EDM) provides many advantages for the shaping of metallic materials. It also provides better surface quality for Ti alloys used in the defense industry. In this study, experiments were carried out with different EDM parameters using the Titanium (Gr2) alloy. A number of novel industrial processes have been developed as a result of advances in technology. For a product to be developed, these novel approaches must be utilized to determine optimum parameters. The Taguchi method was applied in the experiments with EDM. The impact the test parameters had on the performance characteristics of tool wear rate, material removal rate, depth, and surface roughness were analyzed by the variance analysis (ANOVA). Quadratic regression analyses were carried out to reveal the correlation between the experimental results and the predicted values. According to the ANOVA results for material removal rate (MRR), tool wear rate (TWR), depth, and surface roughness, the most effective factor was amperage, at 99.66%, 99.56%, 87.95%, and 81.12%, respectively. The best value for average surface roughness was determined to be 3.29 µm obtained at 120 μs timeon, 8 A, and 40 μs time-off.

Different kinds of carbon (Raw date stone, baked date stone and activated carbon) were prepared and characterized as inexpensive, high surface area, large micropore volume and Effective adsorbents. Material characterization was done using XRD, SEM-EDAX, FTIR and UV-Vis spectroscopy. The activated carbon (AC) possesses a surface area of 571 cm2.g-1. The micropore volume and total pore volume of AC were found to be 0.4785 cm3.g-1 and 0.7267 cm3.g-1 respectively. The effect of backing temperature and activation treatment on surface area and micropore volume were studied. Taguchi factorial design method was used to get the
maximum MB dye adsorption onto the surface of AC sorbent. Contact time (60 min), initial dye concentration (10 mmol), adsorbent dosage (0.25g) and solution temperature (293°K) were found to be the best conditions for the more effective absorption process.

A new solid nanoparticle sorbent (SnO 2 / AC) could serve as high surface area and inexpensive nanocatalyst was prepared. Many properties were characterized by SEM and UV spectroscopy. High surface area, large micro pore volume and total pore volume were found to be 571 m 2 g-1 , 0.4785 cm 3 g-1 and 0.7267 cm 3 g-1 respectively even with very high loaded ratio (60 %) of tin dioxide to Activated Carbon (SnO 2 / AC). Taguchi factorial design method was used to get the maximum MB dye adsorption on the surface of SnO 2 / AC nanoparticle sorbent. Contact time (60 min), initial dye concentration (5 mM) and solution temperature (293 K) were found to be the best conditions for the more effective absorption process.

The surface roughness factor (Ra) of a milled kenaf reinforced plastic are depending on the milling parameters (spindle speed, feed rate and depth of cut). Therefore, a study was carried out to investigate the relationship between the milling parameters and their effects on a kenaf reinforced plastic. The composite panels were fabricated using vacuum assisted resin transfer molding (VARTM) method. A full factorial design of experiments was used as an initial step to screen the significance of the parameters on the defects using Analysis of Variance (ANOVA). If the curvature of the collected data shows significant, Response Surface Methodology (RSM) is then applied for obtaining a quadratic modelling equation which has more reliable in expressing the optimization. Thus, the objective of this research is obtaining an optimum setting of milling parameters and modelling equations to minimize the surface roughness factor (Ra) of milled kenaf reinforced plastic. The spindle speed and feed...

Production of polyol ester from esterification of hexanoic acid (HA) and neopentyl glycol (NPG) was investigated. An optimization experiment, using a Taguchi L9 experimental layout, was used to examine the effect of temperature, pressure, HA:NPG ratio and catalyst amount. The effects of pressure (0.5, 25 and 50 kPa); temperature (423, 453 and 483 K); catalyst amount (0.5, 1.0 and 1.5 % w/w) and HA:NPG ratio (1.5:1, 3:1 and 6:1) were investigated and found to have impacts on the reaction. The percentage contribution of each factors are 43.9, 38.8, 4.3 and 12.9 %, respectively. At the optimal reaction conditions of 423 K, 0.5 kPa, sulfuric acid catalyst 0.5 % w/w and HA:NPG ratio (3:1) more than 99 % w/w neopentyl glycol ester was obtained. Confirmation experiments were performed to demonstrate the effectiveness of this approach and characterization of neopentyl glycol ester was characterized using FTIR and 1 H NMR.

The objective of this study is to compare a set of sustainability metrics between different manufacturing resources applied to high performances machining centers. The research compares distributed scenarios in order to find the optimal conditions that allow the minimum consumed power and the minimum roughness when performing face milling operations of AISI 1045 steel. The set of experiments for the surface machining was carried out considering different path strategies in three main directions for two dimensional movements of the tool. The selected experiments considered the main axis movement, the perpendicular axis movement and a 45 degrees movement. Besides, it was considered the feed rate speed and the cutting depth. The design of experiments was developed with the Taguchi method considering an orthogonal matrix of L27 design type, and three levels of experimental design, and the analysis of variance and noise signal were performed. The methodology to determine the lowest power consumed and the best surface quality allowed to establish the working condition in the most sustainable machining. The results show how the cutting parameters influence in each manufacturing resource.

Brass is widely used in industrial applications due to its excellent machinability and durability, making it well suited for CNC turning operations. Although numerous studies have investigated the optimization of turning parameters, variations in machine tools and cutting conditions often lead to differing conclusions. This study aims to optimize surface roughness in the CNC turning of Brass 36000 using the Taguchi method. An L9 orthogonal array was employed to evaluate the effects of spindle speed, feed rate, depth of cut, and coolant type. Experimental data were analyzed using signal-to-noise (S/N) ratio analysis and analysis of variance (ANOVA) to identify the most influential parameters and optimal cutting conditions. The results indicate that feed rate is the dominant factor affecting surface roughness, contributing to 95.54% of the total variation, followed by spindle speed (1.88%), depth of cut (0.33%), and coolant type (0.18%). The optimal machining parameters were determined as a spindle speed of 1700 rpm, feed rate of 0.1 mm/rev, depth of cut of 1.0 mm, and the use of synthetic coolant (GT41), resulting in a minimum surface roughness of 0.67 µm. These findings demonstrate that precise control of feed rate is critical for achieving improved surface quality in CNC turning of brass.

The present chapter deals with the issues related to the evolution of optimal fuzzy logic controllers (FLC) by proper tuning of its knowledge base (KB), using different tools, such as least-square techniques, genetic algorithms, backpropagation (steepest descent) algorithm, ant-colony optimization, reinforcement learning, Tabu search, Taguchi method and simulated annealing. The selection of a particular tool for the evolution of the FLC, generally depends on the application. Some of the applications have also been included in this chapter.

The present chapter deals with the issues related to the evolution of optimal fuzzy logic controllers (FLC) by proper tuning of its knowledge base (KB), using different tools, such as least-square techniques, genetic algorithms, backpropagation (steepest descent) algorithm, ant-colony optimization, reinforcement learning, Tabu search, Taguchi method and simulated annealing. The selection of a particular tool for the evolution of the FLC, generally depends on the application. Some of the applications have also been included in this chapter.

In this article, the influences of operating variables on the particle size (PS) and particle size distribution (PSD) of emulsion poly(vinyl chloride) in batch reactor were investigated using Taguchi experimental design approach. The variables were temperature (T), water to monomer weight ratio (R), concentrations of initiator ([I]) and emulsifier ([E]), and agitation speed (S). Scanning electron microscope was used together with image analysis software to determine the PS and PSD. Statistical analysis of results revealed that the PS of emulsion poly(vinyl chloride) strongly depends on emulsifier and initiator concentrations, respectively, whereas the other factors have no significant effects in the range of levels investigated in this study. Except initiator concentration, all factors have important influence on the PSD (significance sequence: S > R > T > [E]). It is implied from the greater influence of agitation speed relative to temperature on PSD that the shear coagula...

This article explains the effect of variation on the process parameters while designing a Nano-scaled planar PMOS device in complementary metal-oxide-semiconductor (CMOS) technology for 22 nm gate length. This procedure aims to meet the best combination of fabrication process parameter on the threshold voltage (VTH) and leakage current (IOFF) which was predicted by the International Technology Roadmap for Semiconductors (ITRS). The gate structure of the PMOS device consists of Titanium Dioxide (TiO2) as the high permittivity material (high-k) dielectric and Tungsten Silicide (WSix) metal gate where it is deposited on top of the TiO2 high-k layer. The simulation process was designed using an industrial-based numerical simulator. This simulator was then aided in design with the L9 Taguchi’s orthogonal array method to optimise the best combination of process parameters in order to achieve the optimum VTH value with the lowest IOFF. The analysis results of the factor effect on the SNR i...

Because of high ductility, aluminum alloys, have been widely used as an important base of metal forming industries. But the main week point of these alloys is their low strength so in forming them with conventional methods like deep drawing, hydro forming, etc have been always faced with problems like fracture during of forming process. Because of this, recently using of explosive forming method for forming of these plates has been recommended. In this paper free explosive forming of A2024 aluminum alloy is numerically simulated and during it, explosion wave propagation process is studied. Consequences of this simulation can be effective in prediction of quality of production. These consequences are compared with an experimental test and show the superiority of this method to similar methods like hydro forming and deep drawing.

Biodiesel has been suggested as a fascinating alternative to replace fossil fuels if successful policies to increase renewable energy sources are to be developed. The present work optimizes biodiesel synthesis from waste cooking oil (WCO) by applying the Taguchi approach. The parameters investigated in the work were reaction time, reaction temperature, and the methanol to potassium hydroxide (CH3OH/KOH) ratio. The most significant elements affecting biodiesel yield were found by means of variance (ANOVA) analysis. According to study findings, the ratio of CH3OH/KOH was the most important factor causing process variation. Process variation also came from reaction time and temperature. The study suggests maximizing the ratio of CH3OH/KOH in addition to temperature and time, which are very important for reaching the maximum biodiesel.

A component can be manufactured in several ways. Rapid Prototyping technique is one among the material adding manufacturing process, building up its unique potential in the present scenario. This technique helps manufacture a product from the basic design of the component, thus optimizing the iterative product development process time and creating geometrically complex parts to precise dimensions. In the Rapid Prototyping process, surface finish is critical as it can affect the part accuracy, reduce the post-processing costs and improve the functionality of the parts. This paper presents an ex- perimental design technique for determining the optimal surface finish of a part built by varying Build Orientation, Layer Thickness and keeping other parameters constant using the Fused Deposition Modeling (FDM) process. The design inves- tigates the effect of these parameters on the surface finish. Experiments were conducted using a fractional factorial design with two levels for Layer Thic...

In this research work, temperature erosion wear tests, on composites materials (carbon fiber and glass fiber), were carried out. The tests were made on uncoated and coated materials using a polyester resin (Gelcoat), which is used to protect the leading edge of wind turbine blades against the weather and UV rays and is of interest, in this study, to know the behaviour of this coating subjected to hard particles erosion. The tests were performed at 50 °C, in order to simulate de extreme temperature in the coast of Oaxaca, Mexico, where some wind turbines are installed using blades made of fiberglass coated with gelcoat. Erosion tests were performed in a platform that was developed from the ASTM G76 standard. The rectangular samples had 25×18 mm and thickness of 4 mm. Sea sand from coast of Oaxaca was utilized as erosive particle. Three different impact angles were used 75°, 85°and 90°. The particle velocity was adjusted at 12 m s -1 . To determine the mass loss, the samples were weighed before the test and reweighed every 2 min to measure the amount of mass loss until complete the 6 min of the test. In order to identify the wear mechanisms, Scanning Electron Microscopy was used. The average roughness (Ra) and profiles of the samples tested were determined with a 3D optical profilometer. The results showed that Carbon fiber composite material had 3 times more resistance to erosive wear than fiberglass.

Two aspects of manufacturing systems are explored by means of statistical models. Specifically, reliability growth models and Taguchi-type considerations about quality control are taken upon. The provided discussions help manufacturing engineers apply the presented models.

The Argus reusable launch vehicle (RLV) concept is a single-stage-to-orbit (SSTO) conical, wingedbodied vehicle powered by two liquid hydrogen (LH2)/liquid oxygen (LOX) supercharged ejector ramjets (SERJ). The 3 rd generation Argus launch vehicle utilizes advanced vehicle technologies along with a magnetic levitation (Maglev) launch assist track. A tanker version of the Argus RLV is envisioned to provide an economical means of providing liquid fuel and oxidizer to an orbiting low Earth orbit (LEO) propellant depot. This depot could then provide propellant to various spacecraft, including reusable orbital transfer vehicles used to ferry space solar power (SSP) satellites to geo-stationary orbit. Two different tanker Argus configurations were analyzed. The first simply places additional propellant tanks inside the payload bay of an existing Argus reusable launch vehicle. The second concept is a modified pure tanker version of the Argus RLV in which the payload bay is removed and the vehicle propellant tanks are extended to hold additional propellant. An economic analysis was performed for this study that involved the calculation of the design/development and recurring costs of each vehicle. The goal of this analysis was to determine at what flight rate it would be economically beneficial to spend additional development funds to change an existing, sunk cost, payload bay tanker vehicle into a pure tanker design. The results show that for yearly flight rates greater than ~50 flts/yr it is cheaper, on a $/lb basis , to develop and operate a dedicated tanker.

The Argus reusable launch vehicle (RLV) concept is a single-stage-to-orbit (SSTO) conical, wingedbodied vehicle powered by two liquid hydrogen (LH2)/liquid oxygen (LOX) supercharged ejector ramjets (SERJ). The 3 rd generation Argus launch vehicle utilizes advanced vehicle technologies along with a magnetic levitation (Maglev) launch assist track. A tanker version of the Argus RLV is envisioned to provide an economical means of providing liquid fuel and oxidizer to an orbiting low Earth orbit (LEO) propellant depot. This depot could then provide propellant to various spacecraft, including reusable orbital transfer vehicles used to ferry space solar power (SSP) satellites to geo-stationary orbit. Two different tanker Argus configurations were analyzed. The first simply places additional propellant tanks inside the payload bay of an existing Argus reusable launch vehicle. The second concept is a modified pure tanker version of the Argus RLV in which the payload bay is removed and the vehicle propellant tanks are extended to hold additional propellant. An economic analysis was performed for this study that involved the calculation of the design/development and recurring costs of each vehicle. The goal of this analysis was to determine at what flight rate it would be economically beneficial to spend additional development funds to change an existing, sunk cost, payload bay tanker vehicle into a pure tanker design. The results show that for yearly flight rates greater than ~50 flts/yr it is cheaper, on a $/lb basis , to develop and operate a dedicated tanker.

In many aspects of modern engineering (processes, products, and systems)InIn many aspects of modern engineering (processes, products, and systems) there is a need to optimize multiple responses simultaneously, rather than optimizing one response at a time. The optimization of each individual response may generate as many different results as the responses, which is considered in the study. Then, it may be impossible to decide whether one solution is better than the other. On the other hand, some improvement in one response can significantly degrade at least one or more responses. There are a number of multi-response optimization techniques available. Among these multi-response optimization techniques, the desirability-based approaches take a prominent place because they are less sophisticated, easy to understand and implement, and more flexible with respect to other existing approaches, due to which they are very popular among researchers and practitioners. There are many different ...

ASPEN was a study conducted by Los Alamos National Labs in the early 1960's to examine the benefits of using a Nuclear Thermal Rocket (NTR) for Earth-to-Orbit (ETO) single-stage launch vehicle applications. Using the analysis methods and assumptions of the time, this formerly classified study showed that a significant performance potential might be derived from using NTR engines for the final acceleration phase to orbit (air-breathing engines were used to Mach 11). Given the increased NASA interest in low-cost reusable space transportation, the ASPEN concept has been revisited using contemporary design assumptions and conceptual analysis techniques.

Traditionally mass estimation for conceptual design of advanced launch vehicles has depended on historically -based mass estimating relationships (MERs). Furthermore different organizations have different sets of MERs based on different data sets, and even formulated in different ways. This paper attempts to compare the modern MERs used in the Space Systems Design Lab (SSDL) at Georgia Tech to the 1960's era relationships used in the NAS7-377 report on advanced propulsion design for launch vehicles. Comparisons of the weight breakdowns of a two -stage -to -orbit vehicle are made for between the Marquardt equations and the SSDL equations using two different technology assumptions. The first assumes 1970 technology for a direct comparison of the equations while the second assumes 2015 technology. Additionally technology and material advances are estimated in an attempt to justify the lower weight of the 2015 technology. The SSDL model using 1970 technology weighs in 7% heavier than the Marquardt equations for a comparable two -stage -to -orbit vehicle. When 2015 technology is applied to the same vehicle SSDL equations show a 33% savings, on the entire vehicle, could be made due to technology.

Rocket-based combined-cycle engines are currently under consideration for use on future, reusable launch vehicles. By combining traditional rocket and airbreathing operating modes into a single engine, multi-mode RBCC engines offer a number of advantages for launch vehicle designers including higher trajectory averaged I sp than pure rockets and higher installed thrust-to-weight ratios than pure airbreathers.

This research proposes two methods to investigate the robustness differences between competing types of advanced space launch systems. These methods encompass two different phases of the advanced design process and are used to compare the relative advantages of two concepts in these phases.

A rocket based combined-cycle engine analysis tool suitable for use in the conceptual design environment has recently been established. While this tool was being used in the design environment, new analysis capabilities were desired and areas for improvement were noted. This paper will detail the recent improvements made to the conceptual design tool, SCCREAM, and present the results generated by the added capabilities. The improvements range from an additional engine analysis mode, alternate propellant combinations, and a new user-interface which enables remote execution.

A rocket based combined-cycle engine analysis tool suitable for use in the conceptual design environment has recently been established. While this tool was being used in the design environment, new analysis capabilities were desired and areas for improvement were noted. This paper will detail the recent improvements made to the conceptual design tool, SCCREAM, and present the results generated by the added capabilities. The improvements range from an additional engine analysis mode, alternate propellant combinations, and a new user-interface which enables remote execution.

This research proposes two methods to investigate the robustness differences between competing types of advanced space launch systems. These methods encompass two different phases of the advanced design process and are used to compare the relative advantages of two concepts in these phases.

This paper reports the results of the second phase of a research project to characterize and optimize the design of an advanced launch vehicle for human access to low earth orbit. The vehicle makes use of rocket-based combined-cycle (RBCC) propulsion -a concept combining operating modes of an ejector, ramjet, scramjet, and rocket in a single engine. This research builds on previous work focused on advanced multiple mode propulsion concepts and advanced conical acceleration-class single-stage-toorbit (SSTO) launch vehicles.

The ABLV-GT is a conceptual design for an advanced reusable launch vehicle based on the current NASA Langley ABLV concept. It is a Vision Vehicle class, horizontal takeoff, horizontal landing singlestage-to-orbit vehicle. Main propulsion is provided by Aerojet's 'Strutjet' LOX/LH2 rocket-based combined cycle engine design. The ABLV-GT is designed to deliver 25,000 lbs. to the orbit of the International Space Station from Kennedy Space Center. This paper will report the findings of a conceptual design study on the ABLV-GT performed over the last year by members of the Space Systems Design Lab at Georgia Tech. This work has been sponsored by the Advanced Reusable Transportation Technologies program office at NASA Marshall Space Flight Center. Details of the concept design including external and internal configuration, mass properties, trajectory analysis, aerodynamics, and aeroheating are given.

Any type of machining operation is well influenced by the machinability of work material under processing. This work proposes a graph theory and matrix method based technique for the assessment of machinability of titanium in ultrasonic machining. Identification of various machining attributes along with their relative importance has been considered and analyzed by developing a mathematical function by employing graph theory and matrix method. An attribute digraph is developed, which provides a visual illustration of considered attributes with their relative interactions. This digraph is further represented by using matrix expression. A permanent machinability index for all the experimental runs is also obtained from matrix form demonstration based on attribute digraph. The combination of all the attributes for any machining operation makes this method quite versatile. The results reveal that an experimental run having the combination consisting tool material of titanium, grit size of 500, and power supply of 300 W yields optimized results for machinability.

Sculptured-dies roughing (SDR) has some different objectives that maybe contradicting and therefore needs trade-off among them. Compared to prismatic and rotational shape machining, SDR is more complex considering the sculptured characteristics of machining surface. Layer-by layer approach applied in SDR requires multiple tools selection and determination of the depth of cut for each cutting layer. Those decisions need to be considered in SDR optimization problem. The trade-off between different objectives are required, such as machining residues/cut-off (or coverage) from the roughing process to be traded-off with the machining (roughing) time. This paper presents a stateof-the-art review on cutting layer and cutting tools selection (CLT) by multi-objective optimization for SDR and presents the needs for a trade-off between machining time and cut-off (residual volume) by minimizing machining Time per Volume Coefficient (TVC). The process is conducted simultaneously. A systematic literature review is presented to show the complexity of the geometric related problem, the optimization techniques that have been applied, and the different objectives in SDR, including some multi-objective coverage. Finally, some directions on algorithms for optimizing TVC in TLC problem is presented. Considering the combinatorial problem in CLT, this paper overviews the Multi-Objectives Dynamic Programming approach (MODP) and Metaheuristics Multiple Objective approaches (MOGA etc.) for CLT problem optimization. The results confirm that the optimum tools combination and cutting layer selection could increase SDR efficiency. The paper conclusion discussed recommended metaheuristic approach to trade-off between machining time and residual volume in more complex problem.