bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of Welding Process Parameters on the nilon-6 Plate Friction Stir Welded Joint
Authors: Nugroho A W , Aulistianto I , Budiyantoro C 
Published: April 2024

Abstract
Nylon-6 is one of the most extensively used engineering thermoplastics. Due to its durability, reduced weight, low coefficient of friction, and abrasion resistance, this polymer is an excellent substitute for various materials, including metals and rubber. Despite being those, nylon-6 materials are joined together utilizing multiple welding processes. The current work examined the viability of the friction stir welding (FSW) method on nylon 6 plates that were 4 mm thick to investigate the effect of tool diameter ratio and feed rate on nylon-6 sheets with the FSW method on the tensile properties of the joints. The 4 mm thickness of the nylon-6 plate was cut into the dimensions of 115 mm x 100 mm. The sliced plates were then joined through the FSW process using ST80-based tools with various parameters in the shoulder to pin diameter ratio (D/r ratio) of 10/3, 15/3, and 20/3 and feed rates (FR) of 4 mm/minute, 6 mm/minute, and 8 mm/minute at a rotational speed (RS) of 5800 RPM. Afterward, the weld joint is cut using water jet cutting according to the tensile testing standard ASTM D638 type IV. Following this, characterization of the speci-mens, including macrograph examination, hardness testing, and tensile testing, was carried out. The results show that the highest tensile strength was obtained at a tool diameter ratio of 10/3 mm with a feed rate of 6 mm/minute, with a tensile strength value of 19 MPa reaching up to circa 90% of joint efficiency. The strength of the welded joint then decreases as the diameter ratio of the tool increases with each feed rate. Some defects appeared at the higher tool diameter ratios welded joint, including incomplete fusion, flash, thinning, and lack of bonding. In conclusision the combination of a D/d ratio of 10/3 and a FR of 6 mm/min at RS 5800 RPM can provide the optimal conditions for a strong nylon-6 friction stir welded joint.
Analysis of 3D-Printing Layer Height Pattern Effect to ADC12’s Mechanical Properties Investment Casting Results
Authors: Suprapto W , Irawan Y S , Auliasyah P 
Published: April 2024

Abstract
This study aims to determine the mechanical properties, both hardness and tensile strength of investment casting results from 3D-Printing patterns. In this analysis, the aluminum scrap comes from the piston and will later be Die Casted and become ADC 12. The pattern used Poly Lactid Acid material, then the pattern is printed with varying layer height. After that, analysis was carried out using experimental for surface roughness and hardness of ADC12. The Hardness value is used to get the Tensile strength of ADC12 from empirical aproach. The results of the analysis show that the hardness and tensile strength of the ADC12 casting investment product have decreased due to the increasing value of the surface roughness of the cast product which is influenced by the use of a larger layer thickness.
Effect of Austempering Holding Time Variations of 30, 60, and 90 Minutes at 300 °C on The Microstructure and Toughness of Nodular Cast Iron
Authors: Darmawan A S , Anggono A D , Yulianto A , Febriantoko B W , Hamid A 
Published: April 2024

Abstract
The phases of the nodular cast iron matrix are similar to those of steel. Therefore, heat treatment of steel can be applied to nodular cast iron. A potential heat treatment for nodular cast iron is austempering. This study aimed to determine the effect of austempering holding time at 300 °C on the microstructure and toughness of nodular cast iron. The austempering process begins with austenitizing at a temperature of 850 °C for 60 minutes, then the quenching process is carried out in a salt bath until a temperature of 300 °C is held with variations of 30, 60, and 90 minutes, then cooled to room temperature. Metallographic testing was conducted to determine the phase change before and after the austempering process using a Scanning Electron Microscope (SEM). Meanwhile, impact testing was carried out to determine changes in toughness before and after the austempering process. At a holding time of 30 minutes, metallographic testing on the raw material produced a gray coarse pearlite phase, black nodular graphite surrounded by white ferrite. After the austempering process, gray fine pearlite and black nodular graphite appeared. At the holding time of 60 and 90 minutes, the graphite sizes were bigger. Austempering withholding times of 30, 60, and 90 minutes resulted in impact energy of 4.2, 10, and 11 Joule. From the results of the study, it was concluded that an increase in holding time would increase the size of the graphite and the toughness of nodular cast iron.
Study on Resin-based 3D Printed Product for Spin Casting Mold Making
Authors: Risdiyono  
Published: April 2024

Abstract
Spin casting (centrifugal rubber mold casting) is well known process to produce castings by utilizing inertia. A vulcanized rubber mold is typically used by spinning it at an optimum speed along its central axis. There are many factors influence the quality of casting product, including the quality of mold, the temperature of molten material, the speed and duration of rotation, as well as the pressure upon the mold. This research aims to investigate the quality of casting product when a resin-based 3D printing is utilized to make a model for vulcanized rubber mold. The model is designed by using CAD software and printed layer by layer by using Selective Laser Sintering (SLS) method. Curing process is employed in order to harden the model before placed in the disc-shape silicone rubber. The rubber is then vulcanized so that the mold is formed. Standard edge gate and straight runner are then made to let the molten material flow during casting process. Zinc alloy is used as raw material in the casting process with five variations of rotation speed. Based on the experiment results it is observed that the resin-based 3D printed product can be used as a master model in rubber mold making with some limitations. The resin could not maintain its shape due to the high temperature and pressure during vulcanization process. However, for simple design without any need of very small and detail features, the resin-based 3D printed product still can be used as an alternative.
Ramie Fiber Woven Composite: The Effect of Number of Layers of Woven Fibers on the Thrust Force in the Drilling Process
Authors: Djafar Z , Azis N , Djafar Z 
Published: April 2024

Abstract
Composite material is a combination of two or more materials to obtain better properties and capabilities of the constituent materials. Applications for the use of composites can now be found in industrial equipment to household appliances. To produce these products required machining process. The aim of the study was to determine the effect of the number of layers of woven fiber and the diameter of the drill bit on the thrust of the ramie woven fiber composite in the machining process. The research method was based on ASTM D 5766/D 5766M-02 (Standard Test Method for Tensile Strength Open Hole Laminated Polymer Matrix Composites), the method of making composite material specimens using the hand lay-up method, and the drilling process was carried out with various machining parameters such as composite thickness with variations of 3 layers, 4 layers, 5 layers, and without layers (0 layers). The maximum thrust value obtained was 153.54 ± 3.3 N, with 5 layers of hemp fiber reinforcement, the highest feed rate was 0.15 mm/rev, and the lowest spindle speed was 88 rpm, while the minimum thrust value was 29.52. ± 3.12 N with 0 layers of ramie fiber reinforcement, and the lowest feed rate is 0.05 mm/rev with the highest spindle speed of 1500 rpm.
Optimization of Runner Balance for a Family Product of Injection Molding Process
Authors: Budiyantoro C , Sosiati H 
Published: April 2024

Abstract
A family mold is used in the injection molding process to produce components of different sizes that would normally be assembled into a single product assembly. The uniform quality of each injection molded part is strongly influenced by the filling balance of the mold cavity. The filling balance can be controlled by optimizing the dimensions of runners that are directed towards each cavity. In this paper, an optimization method is proposed that aims at balancing the filling time that maximizes the quality of a family mold cavity. There are two steps proposed in this research, namely theoretical calculations and simulation of runner balanced design using the software. The results of this study can be used as a practical reference in designing a mold for family products to avoid design errors as early as possible. The result obtained from an industrial case study highlighted the effectiveness of the proposed approach in finding the optimal runner dimension by a restricted number of simulations.
The Effect Analysis of ZnO Variations on Corn Starch and Cellulose Biocomposites toward Impact Strength
Authors: Widi I K A , Sutrisno T A , Febritasari R , Ariyanto A 
Published: April 2024

Abstract
Biocomposites made from renewable resources make biocomposites a more viable and promising alternative for the manufacture of metal replacement materials. The use of polyester resin as a matrix in composites does have good mechanical properties. However, it needs development to improve the mechanical properties better, namely by adding corn starch to help the polyester resin matrix. The addition of ZnO and cellulose to strengthen the mechanical properties of the biocomposite. This research was conducted using an experimental method, namely by varying the percentage of 100% Polyester Resin, 2.5% ZnO, 5% ZnO, and 7.5% ZnO to determine the difference in the impact value of the biocomposite. From the impact test results, the specimen with the best mechanical properties will be continued with X-Ray Diffraction testing, to determine the crystallinity index and crystal size. Based on data analysis and discussion, the average impact value of biocomposite 100% Polyester Resin, 2.5% ZnO, 5% ZnO, 7.5% ZnO respectively 0.0139 J/mm2 0.0188 J/mm2 0.0241 J/mm2 0.0168 J/mm2. The best impact value was obtained on biocomposite specimens with a percentage of 5% ZnO. The average impact value obtained is 0.0241 J/mm2. The results of the calculation of the crystallinity index on the specimens with a percentage of 2.5% ZnO, 5% ZnO, and 7.5% ZnO respectively 70.58%, 73.43%, 81.16%, with a crystal size of 28.53 nm, 42.80 nm, 52.21 nm. It can be seen that as the percentage of ZnO increases, the crystallinity index and crystal size increase.
Metallurgical Characterization of Micro Friction Stir Spot Welding (μFSSW) Parameters on Similar Materials AA1100
Authors: Membala S B , Sutresman O S , Arsyad H , Syahid M , Widyianto A 
Published: April 2024

Abstract
The Micro Friction Stir Spot Welding (μFSSW) process is a metal plate welding technique with a relatively thin plate thickness. The advantages of this welding are the higher quality of the weld and the relatively low deformation. This study aimed to determine the effect of depth of penetration, dwell time, and tool geometry on the trend of material flow on the macro-structure of the welds produced in μFSSW technique using AA1100 thin aluminum plates. In this study, the parameters that are changed are the depth of the chisel, dwell time, and tool geometry. In this study, the parameters of the penetration depth were divided into 500 microns, dwell time was split into three lengths of time (300 ms, 500 ms, and 700 ms), and tool geometry was divided into two types of tool geometries (tool-1 and tool-2). In addition, the macro test was carried out to determine the depth of the weld, contour profile, and stretch macrostructure. The results of the macro test will be used to analyze the material flow relationship in each weld zone on the welding results of all existing parameters. Based on the results of the study, the effect of depth of penetration, dwell time, and tool geometry on the weld depth and metallography (hook width, hook height, and effective top sheet thickness) of welds using AA1100 thin plates is influential along with various tool geometries and the deeper the weld penetration and the longer stirring time, although the results are not always directly proportional.
The Limit of Incomplete Information in Inverse Analysis for Hidden Corrosion Inference in Reinforced Concrete
Authors: Ibrahim I B M , Fonna S , Kurniawan R , Huzni S 
Published: April 2024

Abstract
One recurring problem in reinforced concrete structures is hidden corrosion. Detection of hidden corrosion is difficult due to incomplete information that can be measured. To overcome this problem, inverse analysis can be employed. Inverse analysis uses incomplete information from field measurement, and employs optimization to infer further information. Previous research has demonstrated the inference capability of inverse analysis for hidden corrosion detection in reinforced concrete. However, question remains on the limit of incompleteness of measurement data. The aim of this study is to simulate and examine the limit of incomplete information that can be allowed for an effective inverse analysis. The inverse analysis of hidden corrosion in reinforced concrete is formulated as a PDE-constrained optimization. The objective function of the optimization is the distance function between measurement data and FEM simulation. The search space is the PDE boundary conditions configuration. A FEM simulation is used to simulate measurement data by half-cell potential mapping on a concrete block of 2 by 1 meters. To simulate incomplete information, the number of measurement points is varied from 2 to 20 points on the surface of the concrete block. Results show that 20 measurement points are needed to successfully infer hidden corrosion profile. However, when the number of measurement points are below this, the effectiveness of inverse analysis varies and does not seem to correlate to the amount of information (i.e., number of measurement points). Further study is needed if this is due to a fluke or choice of measurement point’s location.
Finite Element Analysis of Polyethylene Pipe with Elliptical Hole Supported by Saddle Fusion Patch with Fin
Authors: Hermawan T L , Sriwijaya R 
Published: April 2024

Abstract
Underground pipe installation is one of the crucial components in supporting industrial activities. Damage to the underground pipe is typical and usually done by patching repair. Analysis of the stress distribution on pipe with patch has been done previously. An analysis needs to be done to determine the effectiveness of the patches and the effect of the growth of the damage. The purpose of this paper is to know the effect of the application of fins on the saddle fusion patch with variations in the number of fins, fin angle orientation, and fin height on the stress distribution on the PE 80 pipe. The research was carried out on a polyethylene pipe with elliptical defects that have been repaired with a saddle fusion patch with a fin as a stiffener. The pipe is a medium-density polyethylene pipe (MDPE80), and the patched is high-density polyethylene (HDPE100). The variation in the research is the fin’s height, the fin’s number and orientation of the fin, and the variation of defect dimension as representative of crack growth. The study was carried out using a finite element analysis tool, ANSYS 2020. The simulation results showed that the addition of fins and the difference in given height on the saddle fusion patch could reduce the stress acting on the cracked pipe. The stress drop that occurs in the addition of the number of fins is not only influenced by the number of fins but also influenced by the orientation of the added fins. The results of this study will provide an overview of the optimal patch thickness after being given reinforcement by fins added to the patch. The hole variations carried out aim to simulate so that the damage that occurs does not repeat itself after being given a patch. Information regarding the optimal and efficient patch thickness becomes an input that is used as a consideration in determining effective and economical repair steps.
Railway track vertical irregularities classification based on vehicle response using machine learning method
Authors: Wikaranadhi P , Alfian S D , Handoko Y A , Palar P S 
Published: April 2024

Abstract
The common method of railway track irregularities assessment currently used, based on track geometry measurement data, is expensive to run, disrupts regular train services, and shows poor correlation with the actual vehicle response when running on a given track section. Vehicle response-based track irregularities assessment methods aim to overcome the shortcomings of geometry measurement-based methods. One of the possible methods is to establish the correlation between track geometry and vehicle response statistically using machine learning. Classification algorithms have been used in previous research for categorizing track sections into discrete classes. In this paper, in addition to discrete classification, the probability for which a track section is categorized as a certain class is presented. Testing results of the trained machine learning classification model showed high accuracy, precision, and recall. The results indicated that this method is suitable for classification of the vertical track irregularities. Further testing was performed with shifted classification threshold. The finding showed that the classification model’s precision and recall could be adjusted by shifting the classification threshold. The result of this study highlights the potential of machine learning classification usage for track irregularities assessment.
Exact closed forms for the transmittance of electromagnetic waves in one-dimensional anisotropic periodic media
Authors: Torres-Guzmán J C , Díaz-de-Anda A , Arriaga J 
Published: April 2024

AbstractIn this work, we obtain closed expressions for the transfer matrix and the transmittance of electromagnetic waves propagating in finite one-dimensional anisotropic periodic stratified media with an arbitrary number of cells. By invoking the Cayley–Hamilton theorem on the transfer matrix for the electromagnetic field in a periodic stratified media formed byNcells, we obtain a fourth-order recursive relation for the matrix coefficients that defines the so-called Tetranacci polynomials (TPs). In the symmetric case, corresponding to a unit-cell transfer matrix with a characteristic polynomial where the coefficients of the linear and cubic terms are equal, closed expressions for the solutions to the recursive relation, known as symmetric TPs, have recently been derived, allowing us to write the transfer matrix and transmittance in a closed form. We show as sufficient conditions that the4×4differential propagation matrix of each layer in the binary unit cell,Δ,a)has eigenvalues of the form±p1,±p2, withp1≠p2, andb)its off-diagonal2×2block matrices possess the same symmetric structure in both layers. Otherwise, the recursive relations are still solvable for any4×4matrix and provide an algorithm to compute theNth power of the transfer matrix without carrying out explicitly the matrix multiplication ofNmatrices. We obtain analytical expressions for the dispersion relation and transmittance, in closed form, for two finite periodic systems: the first one consists of two birefringent uniaxial media with their optical axis perpendicular to thez-axis, and the second consists of two isotropic media subject to an external magnetic field oriented along thez-axis and exhibiting the Faraday effect. Our formalism applies also to lossy media, magnetic anisotropy or optical activity.
Performance Enhancement of PV Module with Cooling Effect using Wet Wicks
Authors: Mumu Tazeen Afrin , Smrity Araf Mim Ahmed , Bhuyan Ayesha , Islam A.K.M. Sadrul 
Published: April 2024

Abstract
Solar energy is one of the most potential sources of power production among all the renewable energies which is eco-friendly and can be much cheaper too. The energy conversion efficiency of the PV module decreases even more due to an increase in operating cell temperature over a certain limit. One way of improving the efficiency of the system is to maintain a low operating temperature by cooling it down during its operational period. This study compares the effects of cooling on the performance of photovoltaic systems. Experiments are performed on the solar panel inclined at a fixed 23.45° angle with the horizontal to the south without active cooling initially to have a set of reference performance parameters for comparison. The polycrystalline PV Module was tested with different cooling methods including Normal water Spray over the front surface, wet jute, and wet woolen material over the back surface of the panel. The cooling of the panels combined with the soiling effect enhances solar efficiency. The wet woolen material results in the most significant efficiency improvement, followed closely by wet jute and normal water spray.
Control of linear instabilities in two-dimensional airfoil boundary layers
Authors: Dandelia Harvansh , Kant Ravi , Narayanan Vinod 
Published: April 2024

Abstract
The present study deals with the control of linear, modal and non-modal growth of perturbations in a trapezoidal wing boundary layer. The asymmetric NACA 2515 airfoil is chosen for the analysis. The boundary layer velocity profiles, at different locations on the airfoil, are obtained using the Falkner–Skan equations. The non-modal linear stability theory is used to obtain the amplification of the initial perturbations, for which the state-space approach is adopted. The control is brought about using a Linear Quadratic Regulator (LQR) controller by the means of addition of fluid momentum in the wall-normal direction from the wing surface. Maximum transient energy growth is calculated across a range of wavenumber pairs, and control is applied to the pair with the highest energy growth. In this numerical analysis, we show that the transient growth is higher towards the trailing edge because of the adverse pressure gradient of the flow. Upon control actuation, the reduction in the transient energy growth of perturbations is achieved up to a maximum of 54.6%.
Strategy for transferring van der Waals materials and heterostructures
Authors: Fan Sidi , Li Xianxu , Mondal Ashok , Wang Wenjie , Lee Young Hee 
Published: April 2024

Abstract
Two-dimensional (2D) layered materials and heterostructures have garnered significant attention for their exploration of uncharted scientific phenomena and their versatile applications. The customization of van der Waals heterostructures heavily relies on their transfer assembly techniques. While traditional dry or wet transfer methods show promise in manipulating 2D materials and heterostructures, challenges such as residues from supporting layers, incomplete substrate etching, embedded bubbles at interfaces, and transfer-induced damages like cracks and wrinkles still pose significant hurdles. In this review, we comprehensively examine the state of transfer technology, identifying the origins of these technical challenges and discussing potential solutions. We specifically focus on strategies developed within the last 3–5 years that aim to address these complex transfer issues, facilitating the integration of 2D materials and heterostructures into existing silicon-based technologies. Finally, we offer perspectives to guide the optimization of each transfer method and inspire future industrial applications of 2D materials.