ARMATUR : Artikel Teknik Mesin & Manufaktur

Effect of Sputtering Time Variation on Mechanical Characteristics and Microstructural Evolution of AISI 4140 Steel

Niki Agastia Mutaqin, Amarullah — Mon, 27 Apr 2026 12:24:02 +0700

AISI 4140 steel is a high‑strength, low‑alloy material commonly used in mechanical components subjected to high load and friction. Although its bulk properties are favorable, surface modification is often required to enhance wear resistance and prolong service life. This study investigates the influence of DC sputtering Titanium Nitride (TiN) deposition time on the mechanical performance and microstructural evolution of AISI 4140 steel. The experimental procedure varied sputtering times at 30, 60, 90, 120, and 150 minutes while maintaining constant processing parameters. Characterization techniques included Vickers hardness testing, wear testing, and SEM–EDX analysis to evaluate coating morphology and coating–substrate interface quality. The results indicate that TiN deposition significantly enhances surface hardness compared to the uncoated substrate. The maximum hardness value of 186.66 VHN was achieved at 60 minutes of deposition, corresponding to a dense, uniform coating with strong adhesion. Prolonged deposition times, however, led to decreased hardness and increased wear rate, attributed to excessive coating thickness, microstructural non-uniformity, and the formation of micro-defects. SEM observations corroborate these findings by revealing notable variations in coating morphology and interface integrity across deposition durations. Overall, the study concludes that sputtering time is a critical parameter in optimizing TiN coatings to improve the surface performance of AISI 4140 steel for engineering applications.

Analisis pengaruh ketebalan dan jenis Coating terhadap kekuatan Adhesi pada Pelat Baja SA 516 Gr 70

Muhammad Syauqi, Rachmad Syarifudin H, Wahyu Dwi K, Sigit N — Mon, 04 May 2026 00:00:00 +0700

SA 516 Gr 70 carbon steel is often used in pressure vessels, requiring a coating system with good adhesive strength to prevent failure due to corrosion. This study analyzes the effect of coating type and thickness on the adhesive strength of SA 516 Gr 70 plates using the pull-off test method in accordance with ASTM D4541. The two coating systems tested were Interbond 2340 (UPC) and Interline 399, with variations in dry film thickness (DFT) of 75 µm, 125 µm, and 175 µm. Surface preparation was carried out through an abrasive blasting process with a cleanliness level of Sa 2½, accompanied by control of roughness profile, salt contamination, dust cleanliness, and control of application environmental conditions to maintain coating quality. Test results show that Interbond 2340 produces higher adhesion values than Interline 399 across all thickness variations, confirming the influence of coating type on coating adhesion performance. A maximum adhesion value of 17.09 MPa was obtained for Interbond 2340 with a thickness of 125 µm, indicating the optimal thickness for increasing the bond strength of the coating to the steel substrate. All specimens met the ASTM D4541 requirements, with Interbond 2340 at a thickness of 125 µm showing the most superior adhesion performance and can be used as a technical reference in selecting a coating system for pressure vessel applications.

Analisis Sifat Mekanik Uji Tarik Material Komposit Serat Karbon–Epoksi 1011l dengan Metode Manufaktur yang Berbeda

Agus Bayu Utama, Kosim Abdurohman, Moh. Habibullah, Rialdi Agustian — Mon, 04 May 2026 00:00:00 +0700

Carbon fiber reinforced polymer composites are widely used in structural applications due to their high strength-to-weight ratio. Manufacturing methods significantly affect fiber impregnation quality, void content, and mechanical properties. This study investigates the effect of different manufacturing methods on the tensile properties of carbon fiber–epoxy 1011L composites with 0° fiber orientation. Three manufacturing methods were used: hand lay-up (HLU), vacuum bagging (VB), and vacuum assisted resin infusion (VARI). A total of 21 specimens were tested using a Universal Testing Machine (UTM) at the National Research and Innovation Agency (BRIN) following ASTM D3039. The results show that The VARI method showed the best mechanical performance with an average maximum point stress (MPS) of 774,31 MPa and an elastic modulus (ME) of 39.313 MPa, followed by the vacuum bagging and hand lay-up methods. The hand lay-up method produced the lowest MPS and ME values, at 507,72 MPa and 20.401 MPa, respectively. The VARI method produces the best mechanical properties compared to the hand lay-up and vacuum bagging methods.

Evaluasi Kinerja Cooling Tower Tipe Counter Flow Mechanical Induced Draft pada Pembangkit Listrik Tenaga Panas Bumi (Studi Kasus: PT Pertamina Geothermal Energy (Tbk), Area Ulubelu, Unit 4)

Agus Apriyanto, Amrul, Hadi Prayitno, Hafizd Zakiyun Al Rasyid — Mon, 04 May 2026 10:48:59 +0700

The cooling tower is one of the vital components in a Geothermal Power Plant (PLTP) system, functioning to cool the condensate water from the condenser before it is reused. This study aims to analyze the effectiveness of a counter flow mechanical induced draft cooling tower at PLTP Unit 4, PT Pertamina Geothermal Energy (Tbk), Ulubelu Area. The data were obtained from field measurements conducted over seven days at fourtime intervals each day. The parameters analyzed include range, approach, and effectiveness, calculated using inlet water temperature, outlet water temperature, and wet bulb temperature. The results show an average effectiveness value of 70.05%, with variations influenced by changes in range and approach values. This effectiveness is close to the design standards stated in the manufacturer’s specifications, indicating that the cooling tower operates with good performance. This analysis provides an overview of the actual equipment condition and can serve as a reference for maintenance and performance optimization in the future.

Studi Komparatif Variasi Ketebalan Pelat Baja ASTM A36 pada Main Steel sebagai Penopang Baterai

Mon, 04 May 2026 10:51:10 +0700

This simulation aims to conduct a comparative study of variations in the thickness of ASTM A36 steel plates to determine the most optimal thickness for supporting the load of batteries, which are currently a critical energy source. The analysis focuses on the values of von Mises stress, displacement, and safety factor. Battery supports are the primary focus of this study, which will compare variations in optimal thickness for batteries that typically require thicknesses of up to 3 to 4 mm; in this simulation, a thinner and optimal solution will be sought. As technology advances and the demands of manufacturing digitalization grow, production processes are increasingly utilizing simulations in Computer-Aided Engineering (CAE) software, making conventional testing more efficient. Using SolidWorks software simulation, a static analysis was conducted to evaluate each variation. ASTM A36 steel plates measuring 1400 mm in length, 70.6 mm in width, and with thicknesses of 1 mm, 2 mm, and 3 mm were selected to accommodate the battery weight. Three battery blocks, each weighing 5 kg, were used in this simulation. ASTM A36 material was selected because it has a high yield strength of 250 MPa. In addition to the parameters mentioned above, dynamic loads with variations of 1.5G and 2G will also be calculated. The optimal strength of the battery mount was determined through simulation in SolidWorks. The results of each thickness variation were then analyzed using a comparative study to determine the optimal thickness based on a comparison of von Mises stress, displacement, and safety factor. Ultimately, the optimal thickness was determined to be 3 mm, with von Mises stress reduced by 32.8% to 82 MPa. Displacement was reduced by 1.08% compared to the two previous variations, specifically 12 mm at the center of the plate. The optimal dynamic load stress occurs at a thickness of 3 mm.

Perancangan Ulang Produk Kruk Dengan Metode Quality Function Deployment Untuk Memenuhi Kebutuhan Penyandang Disabilitas Kaki

Ratna Apriani, Demas Emirbuwono Basuki — Mon, 04 May 2026 00:00:00 +0700

The population of persons with disabilities in Indonesia is currently estimated at approximately 22.97 million individuals, representing around 8.5% of the national population. Among this group, persons with lower-limb disabilities constitute the largest proportion, accounting for roughly 38% of all individuals with disabilities. This category of disability is frequently associated with significant challenges in mobility, including difficulties in walking, ascending stairs, and performing other related movements. Consequently, lower-limb disability users commonly depend on assistive devices such as crutches to support their daily activities. However, complaints often arise when using crutches, one of which is the difficulty of using crutches when traveling, whether by motorcycle or car, due to the elongated size of the device. To address these issues, a Quality Function Deployment (QFD) approach was employed to redesign the crutch in accordance with user needs. Based on this study, improvements were made in two aspects: economic and ergonomic. The product was adjusted to ensure that the price is acceptable to users. In addition, a redesign of the crutch dimensions was carried out, resulting in an increase in height. This modification aims to enhance ergonomic comfort and prevent potential secondary health problems for the users

Analisis Hidrodinamika dan Karakteristik Pressure Drop pada Fotobioreaktor Flat-Panel Sistem Closed-Loop Menggunakan Computational Fluid Dynamics

Tue, 12 May 2026 00:00:00 +0700

Hydrodynamic performance plays a crucial role in determining flow distribution and hydraulic losses inside flat-panel photobioreaktor systems. This study aims to investigate the flow characteristics and pressure drop behavior of a closed-loop flat-panel photobioreaktor using a Computational Fluid Dynamics (CFD) approach. A three-dimensional steady and incompressible laminar model was employed with water as the working fluid. Inlet velocities of 0.01 m/s, 0.03 m/s, 0.05 m/s, and 0.1 m/s were applied to evaluate their influence on velocity distribution, streamline patterns, and pressure drop. A grid independence study was conducted using three mesh densities, and the final mesh with an element size of 0.015 m showed less than 1% variation in pressure drop, confirming mesh-independent results. The simulation results indicate that increasing inlet velocity significantly increases pressure drop and maximum velocity within the reaktor due to flow acceleration near the inlet region. Streamline analysis reveals the formation of recirculation zones in the lower section of panel.

Pelapisan Antikorosi berbasis LDPE dari Limbah Kantong Plastik melalui Metode Catalytic Liquefaction

Mon, 25 May 2026 00:00:00 +0700

Penelitian ini mengkaji pemanfaatan polimer LDPE yang berasal dari limbah kantong plastik sebagai inhibitor korosi pada besi. Proses pencairan LDPE dilakukan dengan menggunakan metode Catalytic Liquefaction dengan katalis ZnCl₂ pada suhu 300°C selama 30 menit. Pengujian karakteristik gugus fungsi dilakukan menggunakan spektrofotometer FTIR, sedangkan efektivitas inhibisi korosi dievaluasi melalui metode pengurangan berat (weight loss) dan Electrochemical Impedance Spectroscopy (EIS) dalam media NaCl 3%, NaCl 5%, HCl 3%, dan HCl 5%. Hasil penelitian ini menunjukkan bahwa polimer LDPE mampu secara signifikan menurunkan laju korosi besi. Efisiensi inhibisi tertinggi diperoleh sebesar 76,84% dalam larutan NaCl 5% dengan konsentrasi inhibitor 5 gram. Analisis EIS menunjukkan efektivitas LDPE ditandai dengan nilai total impedansi yang lebih tinggi dibandingkan tanpa penambahan LDPE (8,21 Ω vs. 5,29 Ω). Adsorpsi molekul LDPE pada permukaan logam mengikuti isoterm adsorpsi Langmuir. Penelitian ini menunjukkan potensi besar dalam pemanfaatan limbah plastik sebagai material antikorosi yang ramah lingkungan.

PEMANFAATAN POLIMER LDPE (LOW-DENSITY POLYETHELENE) LIMBAH PLASTIK SEBAGAI INHIBITOR KOROSI PADA MATERIAL BAJA JENIS LOW-CARBON ASTMA-53 PADA PIPA MINYAK FRAKSI BERAT

Rikki Nababan; Randy Yusuf Kurniawan , Farid Nanda Syanur (Author) — Tue, 26 May 2026 10:36:42 +0700

Penelitian ini membahas permasalahan korosi pada baja karbon ASTM A53 yang banyak digunakan dalam industri minyak dan gas. Tujuan penelitian adalah menganalisis efektivitas pelapisan berbasis limbah plastik Low Density Polyethylene (LDPE) dalam menurunkan laju korosi pada media air formasi. Metode yang digunakan meliputi preparasi spesimen, sintesis larutan LDPE menggunakan pelarut toluena, proses pelapisan методом pencelupan, serta pengujian korosi menggunakan metode kehilangan massa (weight loss) dengan variasi waktu perendaman. Karakterisasi dilakukan menggunakan FTIR untuk mengidentifikasi gugus fungsi pada lapisan pelindung. Hasil penelitian menunjukkan bahwa pelapisan LDPE mampu menurunkan laju korosi secara signifikan dibandingkan baja tanpa pelapisan, di mana peningkatan massa LDPE menghasilkan perlindungan yang lebih optimal.

Pengaruh Jenis Sensor Water Level dan Variasi Tegangan Terhadap Ketinggian Air Pada Tangki Bensin Berbasis Arduino

Yuniarto Agus Winoko, Moch Riduwan — Wed, 27 May 2026 00:00:00 +0700

Cases of vehicle tank leaks throughout 2024-2025 amounted to 23,500 units. The cause of vehicle tank leaks is water vapor (condensation) because the empty space in the tank contains air. Water Level Sensor is a sensor used to detect and measure water levels. The way the Water Level Sensor works by utilizing an open conductor path that is connected when in contact with water, the Water Level Sensor used is HW 37 and HW 38. The purpose of this study is to determine the effect of the type of Water Level Sensor HW 37 and HW 38, variations in working voltage of 3V and 5V and to compare the percentage error value of water level measurements of 5, 10, 15 and 20 mm. The test method uses experiments presented in the form of tables and graphs. The independent variables are the type of sensor and voltage. The dependent variables are the accuracy of water level measurements of 5, 10, 15, and 20 mm. The test results of the Water Level Sensor HW 37 with the best accuracy occurred at a voltage of 5V with a percentage error value of 0.35%, while the Water Level Sensor HW 3 with the best accuracy occurred at a voltage of 5V with a percentage error value of 0.10%.

Waste Analysis in the Chain Wheel Gear Production Process Using the Lean Manufacturing Approach at PT Sinar Agung Selalu Sukses

pitapus rini, Maulana Fajrian, Ratna Agil Apriani — Tue, 02 Jun 2026 10:04:53 +0700

The global automotive industry faces increasing pressure to improve productivity, quality, and cost efficiency to remain competitive. Manufacturing companies are therefore required to minimize waste and optimize production processes. This study analyzes waste reduction in the Original Equipment Manufacturer (OEM) production line at PT Sinar Agung Selalu Sukses, focusing on Chain Wheel Gear (CWG). Between January and July 2025, the production line recorded 9,903 defective units, indicating significant inefficiencies. Lean Manufacturing tools—Value Stream Mapping (VSM), the Borda method, and Fishbone Diagrams—were applied to identify dominant waste and root causes. The analysis revealed a Process Cycle Efficiency (PCE) of 35.9%, below the 50% benchmark, with defect waste identified as the most critical issue. The main contributing factors include material inconsistency, unstable process methods, operator performance, and machine conditions. A 5W+1H-based improvement plan is proposed, including operator mentoring, process standardization, preventive maintenance, and stricter material control. These improvements are expected to reduce defects, shorten lead time, and enhance production efficiency, strengthening competitiveness in Indonesia’s automotive component industry.

ANALISIS PENGARUH JENIS BAHAN BAKAR B0, B30, B35, DAN B40 TERHADAP EFISIENSI THERMAL PLTD BIAK

Syi’ar Mulya Ahmad Pratiknyo, Christiono — Thu, 04 Jun 2026 09:05:30 +0700

Diesel Power Plants (PLTD) play an important role in supplying electrical energy, particularly in island regions and remote areas such as Biak. To support the national energy transition, the government has implemented a mandatory biodiesel policy that has progressively increased from B30 and B35 to B40 in order to reduce dependence on fossil fuels. This study aims to analyze the thermal efficiency of PLTD Biak under B0, B30, B35, and B40 fuel types, as well as their effects on Specific Fuel Consumption (SFC) and heat rate. The research employed a quantitative descriptive approach using actual operational data, including fuel consumption, generator output power, and fuel heating values. The results show that increasing biodiesel content causes SFC to rise from 0.251 liter/kWh for B0 to 0.271 liter/kWh for B40, reduces thermal efficiency from 39.8% to 37.1%, and increases heat rate from 9,045 kJ/kWh to 9,704 kJ/kWh. It can be concluded that B30 provides the best balance between supporting the mandatory biodiesel policy and maintaining operational performance, while B35 and B40 require optimization of operating parameters to preserve efficiency.

Pendekatan Integratif Untuk Peningkatan Efektivitas Layanan dan Operasional Bengkel Otomotif: Systematic Literature Review

Siti Ruqaiyah Baharuddin, Syakia Muflihat — Sat, 06 Jun 2026 00:00:00 +0700

The increasing number of motor vehicles has led to higher demand for automotive workshop services, requiring workshops to improve both service quality and operational efficiency. However, many automotive workshops still face operational problems such as long service waiting times, inefficient workflows, inconsistent service quality, and non-value-added activities. This study aims to identify and analyze various approaches used to improve service quality and operational efficiency in automotive workshops through a Systematic Literature Review (SLR). The study reviewed 15 scientific articles published between 2020 and 2025 related to automotive workshop services, operational improvement, and quality management methods. The analysis focused on approaches such as Service Quality (SERVQUAL), Importance Performance Analysis (IPA), Lean Service, Quality Function Deployment (QFD), Value Stream Mapping (VSM), Six Sigma, Service Blueprint, TRIZ, and Design Thinking. The results show that SERVQUAL is the most widely used method for identifying service quality gaps, especially in responsiveness and reliability dimensions. However, integrated approaches combining service quality methods with operational improvement methods such as Lean Service, VSM, and Six Sigma provide more comprehensive solutions for improving workshop performance. These approaches are effective in reducing operational waste, improving workflow efficiency, minimizing service variability, and enhancing service innovation. The study concludes that improving automotive workshop performance requires an integrated approach involving service quality, operational efficiency, process control, and service innovation.

Pengaruh Konsentrasi Perekat Kitosan Terhadap Sifat Fisik dan Mekanik Papan Partikel Tiga Lapis Berbahan Limbah Batang Jagung Untuk Aplikasi Meja Ramah Lingkungan

Dicky Setyo Purnomo Dicky, Kardiman, Lilik Astari — Sat, 06 Jun 2026 00:00:00 +0700

The growing demand for eco-friendly composite materials has driven research into the use of agricultural waste as a substitute for wood-based raw materials. Conventional adhesives such as urea-formaldehyde (UF) and phenol-formaldehyde (PF) contain toxic formaldehyde compounds, making the development of natural alternatives essential. This study investigates the effect of chitosan adhesive concentration and layer arrangement on the physical and mechanical properties of particleboard made from corn stalk (Zea mays L.) waste, intended for environmentally friendly table applications. Corn stalk particles were processed using a hammer mill and bonded with chitosan adhesive at concentrations of 20%, 25%, and 30%. The boards were hot-pressed at 180°C under 30 MPa for 10 minutes and evaluated according to the Japanese Industrial Standard JIS A 5908:2003, covering density, moisture content (MC), water absorption, thickness swelling, Modulus of Elasticity (MOE), and Modulus of Rupture (MOR). Results showed that density values across all treatments (0.46–0.50 g/cm³) met the JIS standard, classifying the boards as medium density particleboard. Moisture content complied with the standard only at 20% and 25% chitosan concentrations. The 30% chitosan concentration yielded the highest mechanical performance (MOE = 654.98 N/mm²; MOR = 2.81 N/mm²), though all treatments fell below the minimum MOE threshold required by the standard. Water absorption and thickness swelling remained high across all treatments, indicating limited dimensional stability.

Rancang Bangun dan Analisis Kinerja Saluran udara pada Simulator Trainer Airbag

Solachuddin Al Ayyubi, Yuniarto Agus W — Wed, 10 Jun 2026 16:27:09 +0700

Passive safety systems such as airbags are crucial for reducing the risk of fatal injuries in the event of a crash. The deployment speed of an airbag depends heavily on its mechanical design and electronic controls. This study aims to determine the effect of variations in valve channel diameter 2.5 mm, 5 mm, and 8 mm on the deployment response time of the driver-side airbag. The experimental method was conducted using an ATmega328 microcontroller-based airbag vehicle safety simulator trainer. In this test, a solenoid valve was used to regulate airflow with valve orifice diameters of 2.5 mm, 5 mm, and 8 mm. An ADXL345 sensor was used to provide the collision trigger signal to the microcontroller, while an HC-SR04 ultrasonic sensor was used to detect when the airbag began to deploy. Based on experimental analysis, it was concluded that the diameter of the valve channel significantly affects the inflation rate. The smaller the valve channel diameter, the faster the airbag response time. Conversely, the larger the channel diameter, the longer it takes for the airbag to inflate.

Analisis Sifat Mekanik Tarik Komposit Hybrid Matrik Epoxy Serat Rami (Boehmeria Nivea) Dan Serbuk Genteng.

Endar Mukti, Sutrisno, Wahidin Nuriana — Fri, 12 Jun 2026 09:10:55 +0700

Ramie fiber was chosen for its superior mechanical properties and environmentally friendly characteristics as a renewable material, while roof tile powder was used as an inorganic filler to increase stiffness and utilize abundant construction waste. This study aims to analyze the effect of the composition ratio used on the tensile strength of hybrid composites based on natural ramie fiber (Boehmeria Nivea) and roof tile powder with an epoxy matrix, focusing on mechanical testing, namely tensile testing, to analyze the effect of composite material combinations. The research will be conducted using the hand lay-up method, with variations in the volume fraction of epoxy resin (75%) and ramie fiber (0%; 5%; 10%; 15%; 20%; 25%) and roof tile powder (25%; 20%; 15%; 10%; 5%; 0%). The planned mechanical test include several types of test, including tensile test to analyse the effect of composite material combination.