International Journal of Materials and Product Technology (16 papers in press)
A Predictive Modeling of Nanocomposite Coating Microhardness Based on Extremely Randomized Trees
by Hai Guo, Zhao Jingying, Li Xiaoniu
Abstract: Nanocomposite coating is a coating made of particles whose sizes are of nanoscale. The coating has superior performances. The microhardness of the coating is an importance parameter. Currently, experimental method is mainly adopted in the coating's microhardness and performance research, with high research cost and long time period. In this paper, the content of the nano-particles in the plating liquid, current density, duty ratio, addition of additives and ultrasonic power are set as inputs; the micro hardness of the nanocomposite coating is set as output. Extremely randomized trees (ERT) is used to establish a strong prediction model. The research results show that the correlation coefficient of the ERT model is 0.9447, which mean absolute error is 0.0007 and that the root mean squared error is 0.0013. The error between the predictive value and experimental value is small. The prediction performance is the ERT model is superior to that of the single models such as linear regression, Back-Propagation neural network, Radial basis function neural network, support vector regression and Multi-Layer Perceptron etc. and other ensemble learning methods such as random forest, bagging-decision stump and stochastic gradient boosting etc. ERT model can be used for predicting the microhardness of nanocomposite coating, providing an efficient and highly reliable method for new material performance prediction.
Keywords: Nanocomposite coatings; prediction model; extremely randomized trees; ensemble learning.
Optimization of friction stir processing parameters to fabricate AA6063/SiC surface composites using Taguchi technique
by Manu Srivastava, Sandeep Rathee, Sachin Maheshwari
Abstract: Fabrication of metal matrix surface composites is an emerging trend of friction stir processing (FSP) applications. This research proposes production of AA 6063/SiC surface composites (SCs) using FSP. Influences of FSP process parameters viz. tool rotational speed, traverse speed and tilt angle were investigated on the distribution of reinforcement particles and mechanical properties of SCs. Experiments were designed using Taguchi technique. Optimum combinations of process parameters were determined for higher microhardness and ultimate tensile strength respectively using signal/noise ratio graph responses and analysis of variance method. Results revealed that the uniform dispersion of reinforcement particles and appreciable improvement in mechanical properties was achieved by employing optimal combinations of 1400 rpm tool rotational speed, 40 mm/min traverse speed and 2.5˚ tilt angle. About 46% enhancement in microhardness was achieved with optimal parameters as compared to base metal. Conclusions of this research clearly correlate microstructural observations with mechanical properties and reinforcement distribution.
Keywords: friction stir processing; aluminium metal matrix composites; microstructure; mechanical properties; material performance.
Deformation and Fracture Characteristics of Complex Al-Si Alloy during High Speed Forging under Different Processing Conditions
by Khemraj Sahu, A.K. Jha, S.N. Ojha
Abstract: The feasibility of bulk processing of complex Al-Si alloy (Al-18Si-2.5Cu-0.6Fe) has been demonstrated in the present work. Open and closed die forging experiments have been performed using solid cylindrical billets under different conditions of working temperatures, aspect ratios and interfacial friction between top-bottom dies and test samples. The results so obtained, have been critically analyzed and discussed to explain the deformation and fracture behavior of the above Al-Si alloy. Results reveal that due to the presence of hard silicon and intermetallic particles in the alloy, the open die forging of the test sample generates severe surface cracks during deformation under cold and hot processing conditions. However, the high speed closed die forging of above complex Al-Si alloy at elevated temperatures show encouraging results. The forged component so produced is free from surface cracks and possess improved engineering properties.
Keywords: Al-Si alloy; open die forging; closed die forging; elevated working temperature; aspect ratio; surface cracks; strain hardening; primary silicon particles; intermetallic particles; deformation.
Experimental Evaluation of Magnetic Abrasive Finishing Process with Diamond Abrasive
by Vinod Rohilla, Rajesh Sharma, Krishnakant Dhakar, Yogesh Kumar Singla, Kunal Verma
Abstract: Magnetic Abrasive Finishing (MAF) is one of the advanced finishing processes, in which, the work-piece is kept between two magnets and cutting force is controlled by the working gap and magnetic field. In this investigation, cylindrical surfaces of stainless steel were processed using MAF process to examine the Percentage Improvement in Surface Finish (PISF) and Material Removal Rate (MRR). In order to complete the objective, four input process parameters (current, quantity of Magnetic Abrasives (MA), rotational speed, and percentage of diamond abrasives) were varied at different levels. Response surface methodology was adopted to investigate the significance of selected parameters. Further, mathematical models were proposed for response characteristics. Results exhibited that all the input parameters are significant for both the responses. The quantity of magnetic abrasives was found to have a major effect on PISF in comparison to the rotational speed. The minimum surface roughness value of Ra 17.7 nm was obtained.
Keywords: Magnetic Abrasive Finishing; Response Surface Methodology; Percentage Improvement in Surface Finish; Diamond Abrasives; Material Removal Rate.
A continuous straightening formulation based on minimum curvature variation
by Guillermo Poltarak, Sergio Ferro
Abstract: A continuous straightening formulation is proposed in order to smooth the transition between the curved and straight sectors in a continuous caster of metals. This is accomplished by minimising the curvature variation in the straightening sector, taking into account boundary conditions usually found when designing or modifying continuous casting machines. A differential equation is obtained for the bar trajectory which is numerically solved after discretisation. The obtained algorithm is used to compare different casting configurations whose smoothness is quantified in terms of the strain and strain rate along the bar. The continuous straightening configurations developed by this formulation were found to be smoother than typical setups with 1 or 2 straightening points. It was also found that the longer the straightening length, the smoother the transition.
Keywords: continuous straightening; straightening formulation; continuous casting; curvature variation; minimum energy; smooth transition; strain rate; Cornu spiral; Euler spiral.
Influence of powder particles shape and size on the sintered austenitic stainless steel
by Helena Dębecka, Marek Hebda
Abstract: Corrosion behaviour and properties of ready parts produced by powder metallurgy depend on their porosity, especially its volume, spread, type (open or closed) and size. Porosity is inversely proportional to sintered material density, and depends on the size and shape of particles, as well as applied compaction pressure (among others). Furthermore, the particle size influences the sintering process itself in addition to the properties of ready-made parts. The results presented here concern the influence of powder shape and size as well as compacting pressure on the porosity, density, surface roughness and corrosion resistance of sintered 316L stainless steel parts. In addition, the effects occurring during the sintering process were analysed. It was observed that the size and shape of particles significantly affect the sintering process. Most importantly, it was observed that applied compaction pressure is the largest factor on the final properties of the samples.
Keywords: powder metallurgy; austenite; stainless steel; 316L; sponge; spherical; porosity; polarisation curves; corrosion; dilatometry; surface roughness.
Novel Quantification for Silver Ion Generated by the Submerged Arc Discharge Method
by Kuo-Hsiung Tseng, Chih-Ju Chou, Sheng-hao Shih, Der-Chi Tien, Hsueh-Chien Ku, Leszek Stobinski
Abstract: This study used the submerged arc discharge method to produce metal fluid containing nanoparticles and submicron particles, whereby the energy focused by an electric arc was used to dissolve silver metal in deionized water. No additional chemical substances were required throughout the process, which enabled production to be fast and straightforward. Conventional concentration measurement of silver ions (Ag+) uses 200cc of sample solution for every test wherein the Ag+ revert to atoms, resulting in the incapacity of the solution to be reused. This study devised a new quantification method that requires only a trace amount (6cc) of Ag+ solution, and used equations and data from electrical conductivity, concentration, and ultraviolet (UV) absorption values to determine their respective relationships with Ag+ concentration, after which the solution can still be reused.
Keywords: Submerged Arc Discharge Method; Silver ions; electrical conductivity meter; ultraviolet-visible spectrophotometer; Zeta potential ; nanosilver; deionized water ; micro discharge machine system ; electrical conductivity ; Absorbance.
Special Issue on: 3D Printing and Additive Manufacturing
Using additive manufacturing applications for design and development of food and agricultural equipments
by Mohd Javaid, Abid Haleem
Abstract: Additive Manufacturing (AM) has an important role in the future of the globalised world as it provides different technologies to manufacture parts with different types of materials. Food and agriculture sector need extensive customisation to design and develop their equipment depending upon the varied requirement. Thus, through this paper, we are proposing extensive usage of additive manufacturing in these sectors. AM is an effective approach for designing/production of food such as customised pizza, cake, burger and other food items as per the customer requirement. It is efficient due to its reuse of raw material and saves energy as compared to conventional recycling. Chocolate, cakes and shakes are produced as per required shape and colour. AM can also drive major innovation in the agricultural sector. It has great capabilities to produce physical models of agricultural equipment and making its way directly onto the farms. This technology can easily print functional prototypes and can further be tested for obtaining design flaws or any other specific agricultural requirements before the product is produced in a factory. The new design/redesign of agricultural equipment meets the unique demand of the special consumer. These customised products are appropriately designed and manufactured through this new rising technology. This technology will bring the agricultural industry to that point where the farmer will purchase agricultural equipment according to the choice of design, shape and size. Before starting full production of agriculture equipment, we can easily make a physical prototype.
Keywords: Additive Manufacturing (AM); 3D Printing; Rapid Prototyping; Food printing: Agriculture equipments; Design; Product customisation.
Investigation of Professional Design Practice: a Framework for Designing Plastic Consumer Products for Additive Manufacturing
by Wei Liu, Zicheng Zhu, Songhe Ye, Xiaoneng Jin, Guanghe Yan
Abstract: Revolutionary advances in plastic additive manufacturing (AM) have enabled it to evolve to be an economic viable production method for manufacturing consumer products in our daily lives. The capability of creating complex structures opens up vast design freedoms, which consequently requires new design mind-sets and methods to be developed to take advantage of this emerging technology whilst minimising inherent process drawbacks. This study investigates professional design practice in design for plastic AM. A framework that shows an effective way to design products is developed, enabling efficient low to medium volume production using plastic AM processes. The major factors and design considerations including AM process characteristics, materials, product appearance, functionality and production economic viability that affect the design of a consumer product are described. A case study of a night lamp manufactured by selective laser sintering is conducted, demonstrating that plastic AM is a feasible and reliable production route for consumer goods.
Keywords: Design for additive manufacturing; 3D printing; Plastic consumer goods; Design method; Design process.
Evaluation of additive manufacturing technologies for dimensional and geometric accuracy
by Abdulrahman Al-Ahmari, Mohammed Ashfaq, Syed Hammad Mian, Wadea Ameen
Abstract: The need for product customization and shorten design cycle have led to the evolution of Additive Manufacturing (AM). It refers to a process where components are built up through the deposition of material in layer by layer manner. It allows fabrication of complex 3D parts with greater flexibility and freedom. In spite of the numerous benefits offered by AM processes, their primary applications are limited to prototyping. A number of unresolved issues can be cited, which have curtailed their implementation. Among the serious problems faced by AM technologies are poor dimension and geometric accuracy as well as low surface finish. Henceforth, further expansion and better performance entail an increased understanding of AM systems.
A wide range of AM technologies, with variations in accuracy and surface finish is available in the market. Most often, the dimension and geometric accuracy of AM machines do not persistently conform the assertions of the manufacturer, and thereby desired accuracy of parts is often difficult to attain. The goal of this work is to evaluate three different AM processes. The three most popular AM processes such as fused deposition modeling (solid-based), stereolithography (liquid-based) and electron beam melting (powder-based) are evaluated for dimension and geometrical accuracy. This study has been undertaken to provide engineers and designers with useful information about the expected accuracy that can be achieved from different AM systems. The results of this work can be used to identify possible process improvements in the design and control of AM technologies.
Keywords: Additve Manufacturing (AM); 3D Printing; Fused Deposition Modeling (FDM); Stereolithography (SLA); Electron Beam Melting (EBM); Benchmarking; Accuracy.
Investigation of parameters influencing mechanical properties in SIS by using RSM
by SAGAR BALIGIDAD, Chandrashekhar U, Elangovan K, Shankhar S
Abstract: Selective Inhibition Sintering (SIS), one among the emerging Layered Manufacturing technology, wherein parts can fabricate directly with the source from CAD template. The key challenge of this process is to select optimal control parameters to fabricate parts with desired dimensions to meet industry requirements. This study considers heater power, layer thickness, heater feed rate, roller feed rate, and bed temperature are as candidate factors to optimize by using the face-centered composite method of response surface methodology. Response Surface Methodology (RSM) was employed to plan the experiments with five factors-three levels and face-centered central technique is followed to plan the design. Analysis of variance (ANOVA) technique was used to verify the adequacy of the developed models. The experiments are performed on polyamide (PA12) material through by a novel selective inhibition sintering process. Experimental results revealed that mechanical properties of fabricated parts increased with the decrease in heater power, layer thickness and with the increase in heater feed rate, roller feed rate. The microstructural evaluation was also performed to justify the surface morphology. Sensitivity analysis is carried out to measure the impact of process parameters on mechanical properties. The results of these studies are validated and optimal working parameters were determined to fabricate the parts with the greatest strength.
Keywords: Selective inhibition sintering; Optimization; ANOVA; Response Surface Methodology; Sensitivity.
Selection of 3D printer based on FAHP integrated with GRATOPSIS
by Raghavendra Prabhu Sundarraj, Ilangkumaran Mani
Abstract: The purpose of this paper is to evaluate and select the suitable three Dimensional (3D) printers for Centre of excellence of academic institution. The selection involves various conflicting criteria such as Build volume, Speed, Layer thickness, Extruder, Machine cost and Support material cost. In order to overcome this conflicting nature of the evaluation criteria, Hybrid Multi Criteria Decision Making (MCDM) model is proposed. Fuzzy Analytical Hierarchy Process (FAHP) is integrated with Grey Relational Analysis (GRA) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) is proposed as a model to evaluate the suitable 3D Printer. FAHP is used to define the weights of criteria and GRA-TOPSIS is used to attain the final ranking of 3D printers. In this study ten 3D printer models and six evaluation criteria are considered for the evaluation process.
Keywords: 3D printer; MCDM; FAHP; TOPSIS; GRA-TOPSIS.
Estimating percentage contribution of process parameters towards build time of FDM process for components displaying spatial symmetry: A case Study
by Manu Srivastava, Sandeep Rathee, Sachin Maheshwari, T.K. Kundra
Abstract: Generative manufacturing is an innovative technology which is almost thirty years old. It has the ability of quickly transforming concept into physical models. The design cycle is contracted manifolds by utilizing these techniques. One of a versatile generative manufacturing technique is fused deposition modelling (FDM) which is used for production of robust and economical prototypes. In the present research, effect of percentage contribution of critical process parameters on the build time requirements of the FDM process is examined for the given build volume in Fortus 250mc modeller. ABS P430 cubical and spherical primitives of constructive solid geometry, which display spatial symmetry in a given build volume, are chosen as work piece. Response surface methodology is utilized as the statistical tool for experimental design and modelling. This work is an attempt towards explicitly defining the process parameters which affect the build time and their percentage contribution. It has been established by this research that the percentage contribution of slice height outweighs the effect of air gap and orientation towards the estimation of build time. Other FDM build parameters like width and inclination of rasters as also width of contours contributes relatively less towards the build time and material volume quantities.
Keywords: Additive manufacturing; fused deposition modelling; symmetric CSG primitives; build time.
Special Issue on: A Synergistic Approach in IR4.0 for Product Technology Development
Characterization of microstructure, mechanical properties and fracture mode of the dissimilar joining of AISI 304 stainless steel and DP780 dual phase steel by resistance spot welding
by Masoud Sabzi, Sadegh Moeini Far , Saeid Mersagh Dezfuli
Abstract: Microstructure, mechanical properties and fracture mode were investigated for the dissimilar joining of AISI 304 steel and DP780 steel by resistance spot welding. First resistance spot welding was utilized with a current density of 8kA, holding time after welding of 10 cycles, and 5kN electrode force. Then, to evaluate the microstructure, hardness profile and tensile-shear strength of weld nugget, scanning electron microscopy (SEM), Vickers micro-hardness and tensile-shear tests were carried out, respectively. Microstructural evaluations showed that in the dissimilar joining of DP780 - AISI 304 stainless steel, fusion zone (FZ) microstructure was martensitic and some grains were also coarsened in heat affected zone (HAZ). Moreover, HAZ in AISI 304 stainless steel side remained completely austenitic, while HAZ in DP780 dual phase steel transformed to martensite. Micro-hardness results showed that in the dissimilar joint of DP780 - AISI 304 stainless steel, FZ hardness was higher than base metals (BM) of both sheets of steel. Additionally, HAZ in DP780 dual phase steel side had higher hardening ability than other joint areas. Results of tensile shear tests of the dissimilar joint of DP780 - AISI 304 stainless steel, indicated that the joint had the tensile shear strength of 15 kN along with the occurrence of severe plastic deformation.
Keywords: Resistance spot welding; DP780 dual phase steel; AISI 304 stainless steel; Microstructure; Hardness profile; Tensile – shear strength.
Effect of Ball Milling Time on the Properties of Nickel Oxide-Samarium-Doped Cerium Composite Anodes for Solid Oxide Fuel Cells
by N.O.R. FATINA RADUWAN, Muhammed Ali S.A., Mustafa Anwar, Andanastuti Muchtar, Mahendra Rao Somalu
Abstract: The powder characteristics of composites under different processing conditions, such as milling time, must be elucidated before fabricating electrodes with porous structures for fuel cell applications. Milling time is an important parameter in producing pure composite powders with fine crystallite size and affects the densification of the sintered pellet and the electrical performance of the cell. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses were conducted to characterize nickel-oxidesamarium-doped cerium (NiO-SDC) powders milled for different durations (2, 12, and 24 h). Field-emission scanning electron microscopy (FESEM) analysis was performed to clarify the porosity of the sintered pellets. Density was determined using Archimedes method and was found to decrease after the reduction of the anode pellets. The XRD analysis of the composite anodes showed good chemical compatibility between the NiO and SDC. The TEM analysis of the as-prepared powders indicated that the particle size of the powder was within the nanometer range. This finding was confirmed by the FESEM micrograph of the sintered pellets. The porosity of the sintered pellets (before and after reduction) ranged from 20% to 40% and was considered sufficient for anode materials in solid oxide fuel cells (SOFC).
Keywords: ball milling time; NiO-SDC; composite anode; particle size; porosity; density; solid oxide fuel cell.
A systemic study on hydroforming process of exhaust pipe FE simulation and experiment
by Kuanxin Liu, Ning Guo, Shunqi Zheng, Kemin Xue
Abstract: Hydroforming process of tube parts is widely used in many industries due to the virtues of weight reduction and high strength and stiffness. The exhaust pipe hydroforming process is investigated systemically combined FE simulation with experiments. The FE simulation model for hydroforming process is established after solving several key technologies based on the ABAQUS software, and the validation is carried out compared with experiments. And then, the effects of process parameters on forming quality are studied by using the FE simulation model. The optional process parameters are obtained based on the simulation model and orthogonal experimental analysis. Finally, three typical loading paths are proposed and tested, and the guidance for loading path is given. Based on these developments, the exhaust pipes are manufactured by hydroforming in a short period and low cost.
Keywords: hydroforming process; exhaust pipe; optional process parameter; orthogonal experimental analysis.