Pengaruh Setting Parameter pada Slicing Software terhadap Surface Roughness Objek 3D Printing menggunakan Metode Taguchi

<p>Teknologi FDM (<em>Fused Deposition Modelling</em>) merupakan salah satu teknologi yang digunakan untuk membuat objek 3D. FDM sering disebut sebagai teknologi yang sudah mampu mengubah dunia manufaktur dewasa ini. Namun teknologi FDM memiliki kelemahan karena teknologi ini menggunakan proses <em>building per layer </em>membuat permukaan yang dihasilkan terlihat memiliki garis yang menunjukan batas antar <em>layer </em>sehingga mempengaruhi kekasaran pada permukaan produk cetak. Penelitian ini menggunakan filamen <em>Super Tough</em> PLA (ST.PLA). Tujuan penelitian ini adalah untuk mengetahui pengaruh parameter proses terhadap kekasaran permukaan objek cetak dan untuk mengetahui seting parameter proses yang menghasilkan kekasaran permukaan terbaik dari parameter proses yang digunakan. Penelitian ini menggunakan metode Taguchi dengan matriks ortogonal L₂₅(5⁶). Parameter proses yang akan dipilih dan dianalisis dalam penelitian ini adalah<em> layer thickness, printing speed, nozzle temperature, orientation, flowrate</em>, <em>cooling speed </em>dan respon yang diamati adalah kekasaran permukaan objek cetak. Untuk mengatasi permasalahan <em>noise</em> (gangguan) maka dicetak masing-masing tiga kali replikasi Selanjutnya parameter proses tersebut akan dianalisis menggunakan Analisis Varian (ANOVA). Berdasarkan data hasil pengukuran kekasaran permukaaan objek cetak, maka diperoleh parameter proses yang memberikan pengaruh paling besar terhadap kekasaran permukaan objek cetak dengan menggunakan filamen ST-PLA adalah <em>layer thickness</em> dengan nilai F hitung sebesar 129,96, <em>flowrate</em> dengan nilai F hitung sebesar 6 dan <em>orientation</em> dengan nilai F hitung sebesar 3,03. Seting parameter proses yang menghasilkan nilai kekasaran permukaan terbaik objek cetak adalah 0,10 mm yaitu pada eksperimen nomor lima (Exp. No. 5) dengan rata-rata 12,61 µm, dengan pengaturan <em>layer thickness</em>, 45 mm/s pada pengaturan <em>printing speed</em>, 210˚C pada <em>nozzle temperature</em>, 0˚ pada <em>orientation</em>, 110% pada pengaturan <em>flowrate</em> dan 40% pada pengaturan <em>cooling speed</em>. Seluruh parameter proses tersebut disetting pada <em>slicing software</em> ideamaker 3.6.1. dalam menghasilkan G-Code objek cetak.</p>

Improving the Performance of Split Air Conditioner by Adding Nano Silver to the Compressor Oil

A high demand on the energy and power has brought scholars more attention to investigate new ways to reduce the energy consumption. The aim of this research is reducing the power consumption required for air conditioning to cool the room by adding nanomaterials to the compressor oil at a mass concentration of 0.15%. Two models of chambers with dimensions (2 x 2 x 2) meters were fabricated to represent the test section and connected to a 1ton compressor, one operating with natural oil as a standard basis for comparison, while the other one with Nano-oil prepared in the laboratory. The mass concentrations of 0.15% of silver nanoparticles (Ag) were prepared, and the stability of the nanoparticles was tested by direct observation for different time periods. The results indicated that the performance of the air conditioner was better with the addition of nanoparticles to the compressor oil compared to the pure oil in the compressor. Reducing energy consumption in the cooling system by (19%). Also, it was found that there is an increase in the cooling speed of the nanotechnology system by (6%)as well as in the efficiency of the Nano-oil system compared to the regular system by (13%). This study showed that the thermophysical properties of the cooling oil increased by increasing the weight ratios of solid nanoparticles by (12%).

Research on the Reciprocating Motion of the Man-Machine Indirect Piston and the Efficiency of Internal Friction

In the process of technological progress and development, many industries are moving towards artificial intelligence (AI) technology, which is a construction and combination of multi-thinking technology. But in terms of structure, material development and diversification, the source of ideas is still inseparable from the natural world. Therefore, when faced with solving problems, many scientists not only conduct in-depth research on changes in cells, tissues and expansion, to solve the multi-dimensional movement of current technology, but also non-destructively explore the thermal effects of friction. Self-generated lubrication or external additives are used to solve the demand, so that the reciprocating movement of the piston can be more effective, and each cycle can be achieved. According to research and discussion, in each cycle, heat engine and cooling, speed movement frequency and lubrication method are different, which not only makes the piston have different effects, but also the reaction and sensitivity will greatly change, which makes it necessary to stop resting. Therefore, this research is primarily aimed at exploring the reciprocating motion of the human-machine “Indirect piston” and the efficiency of internal friction. The purpose is to have a more in-depth study of the piston theory, so as to have a deeper foundation for the movement of derived multi-dimensional angles in the future. In the future, there will be better development in injection, piston mechanism, and lubrication.

Microstructure features and formation mechanism in a newly developed electroslag welding

Electroslag welding (ESW) is known to show higher heat input than electrogas welding (EGW), resulting in poor low-temperature toughness. However, a newly developed ESW (dev. ESW) method using low-resistivity slag bath exhibited excellent low-temperature toughness as a result of lower effective heat input than conventional EGW, as demonstrated by the faster cooling rates measured in weld metals and estimated using finite element method analyses. This led to much shallower molten pool in the dev. ESW, resulting in much finer columnar grains and thinner centerline axial grains. High cooling speed in the dev. ESW method appeared to contribute to increased acicular ferrite proportion. The uniform microstructure with large acicular ferrite proportion and small number of inclusions in the weld metal permitted the dev. ESW weld metal to possess little variation in Charpy impact energy across the center of weld metal.

Analisis Proses 3D Printing terhadap Pengujian Impak Metode Charpy Pada Material PLA+

Pada era industri perkembangan teknologi pada saat ini telah mengalami kemajuan yang sangat pesat, salah satunya adalah teknologi 3D printing atau juga dikenal sebagai additive manufacturing. Salah satu teknologi 3D printing yang terkenal adalah Fused Deposition Modelling (FDM). Prinsip kerja FDM adalah dengan cara ekstrusi termoplastik melalui nozzle yang panas pada melting temperature selanjutnya produk dibuat lapis perlapis. Teknologi 3D printing adalah proses pembuatan benda padat dari sebuah file digital. Penelitian ini menggunakan metode eksperimen, dilakukan pada mesin 3D printing FDM model Prusa area dengan menggunakan nozzle 0,4mm. Material yang digunakan adalah filamen PLA+ dengan diameter 1,75mm variasi parameternya nozzle temperature (205oC, 215oC, 225oC), Cooling speed (100%, 90%, 80%), infill type (grid, lines, triangles, Tri hexagon, cubic, cubic subdivision, octet, quarter qubic, concentric, zigzag, cross, cross 3D dan gyroid). Penelitian ini menggunakan 39 sampel dengan tujuan untuk mengetahui hasil uji impak tertinggi dan terendah dengan pengujian impak dari parameter yang ditentukan yaitu orientasi printing 90o. Hasil dari pengujian impak tertinggi sebesar 0,00548 Joule/mm2 dengan ekperimen nomor 32 infill geometry (cubic Subdivision), cooling speed 80% dan nozzle temperature 225ºC. Sedangkan nilai uji impak terendah sebesar 0,00084 Joule/mm2 dengan ekperimen nomor 14 dan 17 infill geometry (grid) dan (Tri hexagon), cooling speed 90%, nozzle temperature 215ºC dan ekperimen nomor 27 infill geometry grid, cooling speed 80%, nozzle temperature 225ºC. hasil pengujian impak menggunakan spesimen PLA+ didapatkan nilai uji impak sebesar 0,00548 Joule/mm2, dengan ekperimen nomor 32 infill geometry cubic subdivision, cooling speed 80%, nozzle temperature 225oC.

Optimasi Parameter Proses 3D Printing Terhadap Kuat Tarik Material Filamen PLA + Menggunakan Metode Taguchi

FDM (Fused Deposition Modeling) is one of the methods often usen by researchers in 3D printing technology which is used to print filaments products as a materials, due to the easy technique for 3D printing with relatively low production costs. One of the materials that can be processed in a 3D printing machine ia PLA+. Research in tensile testing has been done on PLA and ABS filaments. Meanwhile, tensile testing using PLA+ filaments is still rarely done. From these problems, research is needed to get the optimal process parameters on the 3D printing machine to get the highest tensile strenght value using PLA+ filaments. This research uses the taguchi method, carried out on a PRUSA area model FDM 3D Printing machine with dimensions of 300mm x 300mm x 350mm using a nozzle size of 0.4mm. The material used is PLA + Esun filament with a diameter of 1.75 mm with a variety of printing speed parameters (30 mm/s, 35 mm/s, 40 mm/s, 45 mm/s, 50 mm/s), nozzle temperature (1950C, 2000C, 2050C, 2100C, 2150C), layer thickness (0.10mm, 0.15mm, 0.20mm, 0.25mm, 0.30mm), cooling speed (20%, 40%, 60%, 80%, 100%), orientation (00, 300, 450, 600,900) which will be determined in ideamaker 3.6.1 to produce 75 printed samples. This research aims to determine the optimal tensile strength value. From the research results there is an optimal tensile strength value, namely in experiment 10 with the parameter values of printing speed (35 mm/s), Nozzle Tenperature (2150C), Layer Thickness (0.10mm), Cooling speed (20%), and Orientation (450). with a tensile strength value of 48.1 MPa from 3 replications.

Analisis Laju Penurunan Temperatur di Dalam Ruangan Menggunakan AC Low Watt 0,5 HP

Heat absorb ability split AC is the most important factor in the cooling speed on room temperature. The rate of temperature drop is determined by many factors, including compressor power. Nowadays, there are many Split AC are produced that have low power (low Watt), so that research is needed to determine the cooling speed in a room. This study uses a low watt split AC with a power of 0.5 HP. The distance from the evaporator and the outside temperature are used as independent variables, while the rate of temperature reduction or cooling speed in the room is used as the dependent variable. The results showed that the distribution of room temperature and the rate of temperature reduction in the room varied based on the position of the distance to the location of the AC Split Low Watt. The lowest temperature and reduction rate in the room occurs at a distance of 2 m and 3 m in front of the AC location. The outside temperature or the temperature around the location of the AC condenser affects the temperature distribution at each distance in front of the AC. When the outside temperature is low, the temperature conditions at a distance of 1 m, 4 m, and 5 m have a significant difference. While the high outside temperature conditions, the temperature at a distance of 1 m, 4 m, and 5 m, namely the positions close to the wall, is almost the same. Kata kunci: AC, split, low watt, evaporator

Using P(Pressure)-T(Temperature) Path to Control the Foaming Cell Sizes in Microcellular Injection Molding Process

Microcellular injection molding technology (MuCell) using supercritical fluid (SCF) as a foaming agent is one of the important green molding solutions for reducing the part weight, saving cycle time, and molding energy, and improving dimensional stability. In view of the environmental issues, the successful application of MuCell is becoming increasingly important. However, the molding process encounters difficulties including the sliver flow marks on the surface and unstable mechanical properties that are caused by the uneven foaming cell sizes within the part. In our previous studies, gas counter-pressure combined with dynamic molding temperature control was observed to be an effective and promising way of improving product quality. In this study, we extend this concept by incorporating additional parameters, such as gas pressure holding time and release time, and taking the mold cooling speed into account to form a P(pressure)-T(temperature) path in the SCF PT diagram. This study demonstrates the successful control of foaming cell size and uniformity in size distribution in microcellular injection molding of polystyrene (PS). A preliminary study in the molding of elastomer thermoplastic polyurethanes (TPU) using the P-T path also shows promising results.

Structure and Ion Conductivity Study of Argyrodite (Li5.5PS4.5Cl1.5) according to Cooling Method

All solid-state batteries (ASSBs) are now anticipated to be an ultimate solution to the persistent safety issues of conventional lithium-ion batteries (LIBs). Contemporary society’s expanding power demands and growing energy consumption require energy storage with greater reliability, safety and capacity, which cannot be easily achieved with current state-of-the-art liquid-electrolyte-based LIBs. In contrast, these conditions are expected to be met by implementing ASSBs with high-performance solid-state electrolytes (SSEs). In this work, we altered the microscopic structure and Li diffusional behaviors of argyrodites (Li_6-xPS_5-xCl_1+x), which were precisely monitored with cooling protocols. It was shown that, at the cooling speed of -3 ^oC·h^-1, as the cooling rate decreased, impurities in Li_5.5PS_4.5Cl_1.5 such as LiCl and Li₃PO₄ gradually diminished and eventually disappeared. At the same time, differences in the lattice sizes of Li_5.5PS_4.5Cl_1.5 crystallites gradually decreased, resulting in a single phase Li_5.5PS_4.5Cl_1.5. It was also found that the Cl content of the 4d crystallographic sites increased, eventually contributing to the improvement in ionic conductivity. This work also revealed the effect of cooling rates on the crystallographic atomic arrangements, which became weaker as a decrease in x. The correlations between ionic conductivities and structural features were experimentally verified via XRD and solid-state NMR studies.