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This article focuses on the production of tensile test (ASTM D638-03) specimens using fused deposition modelling technique as preliminary study for preparation of 3D-printed SUAV wings. Carbon-PLA (nylon 6/66 copolymer adding with 20% of carbon fiber) was used as 3D filament. There were 7 printing orientations: 0o, 15o, 30o, 45o, 60o, 75o, and 90o based on tensile axis with 3 specimens for each direction (21 specimens in total). Printing parameters were set using open-source slicing application CURA. It was found delamination and fracture outside the gauge length causing high deviation of the mechanical properties value. So, the result of the testing test seems like do not comply with theoretical aspect of relationship between fiber orientation and tensile properties of composite materials. Taking care of printing parameters and increasing the number of specimens has an opportunity to achieve high precision results since precise data is crucial as a starting point for the development of SUAV wings.

Gray cast iron has graphite flakes which makes it relatively weak and brittle. The addition of magnesium to gray cast iron resulted in nodular cast iron which has spherical graphite. The aim of this research was to investigate the changes in the microstructure and strength due to the addition of magnesium to gray cast iron. Microstructure observations were made by metallographic testing using Scanning Electron Microscopy and Energy Dispersive Spectroscopy. Tensile testing was carried out to measure the yield strength, tensile strength, and modulus of elasticity. The addition of magnesium to gray cast iron was observed to increase the yield strength by 179%, tensile strength by 238%, and decrease the modulus of elasticity by 94%.

The research objective is to investigate the formation of new compounds and the mechanical properties of Double Side Friction Stir Welding (DS-FSW) welding with Cu particle reinforcement. Aluminum alloys of AA6061 and 12 μm Cu powder were chosen as the main materials. The addition of Cu particles is conducted in single groove and double groove. The DS-FSW process uses CNC milling with a feed rate of 80 mm/minute and 1000 rpm of tool rotation. Observation of the microstructure was carried out by using optical metallography, and X-ray diffraction. Microhardness testing was done to determine the mechanical properties of the material. The results showed that the increase in the hardness value of 23.39% occurred in the double groove material. MMCs detected were Al2Cu, and AlCu2Mn.

Using the nanoindentation technique, the creep deformation behavior of Zr55Co25Al15Ni5 bulk metallic glass (BMG) in the range of 0.94–1.03 glass transition temperature (Tg) and different loading rates was studied. The Maxwell–Voigt model was applied to describe the deformation and relaxation kinetics of BMGs near the glass transition. According to the results, the serrated behavior of deformation, as the indicator of shear events, disappeared at higher loading rates and temperatures. This event was due to the high rate of defect formation and propagation at higher temperatures under the indenting process. Based on the Maxwell model, it was found that the creep deformation can be divided into two distinct characteristic relaxation times in the range of 0.1–0.68 S and 8.3–24.8 S, respectively. At the higher temperatures, the creep deformation tends to have higher relaxation times, which corresponds to the viscoplastic behavior of material.

Nodular cast iron is a type of cast iron with spheroid graphite surrounded by ferrite matrix and / or pearlite. The size of the graphite and its matrix affects the mechanical properties of the cast iron. This research was conducted to investigate the effect of Magnesium composition on strength, stiffness and toughness of nodular cast iron. Magnesium addition is performed by adding FeSiMg alloys. After that, the composition of magnesium was investigated by using spectrometry. Then tensile test was conducted to obtain the yield strength, tensile strength and modulus of elasticity. Further, impact test was performed to determine the impact energy needed to break the material. The result showed an increase of yield strength, tensile strength and stiffness and a decrease of toughness.

Sand casting is one of manufacturing process that still exist today. Numerous products are produced to serve industrial and domestic use. Defect could lead to product performance, and unfortunately inevitable in a casting process. This paper aim to investigate typical defect resulted from sand casting process. An aluminum cooling fan was selected as the model since it has complicated shape with different thicknesses. The casted fan was investigated under photo micro for defect analysis. Porosity, gas inclusion, pinhole, and shrinkage were found as the common defects occured at different part of the fan.

The objectives of the study is to investigate the formation of intermetallic compound and the mechanical properties of the underwater welding. AISI 4012 steel was selected as the material and two types of electrode E6013 and E7018. The variations of electric current used in this study were 80,100, and 120 amperes. The underwater welding was conducted in plain water pool and 3 meters depth by using SMAW. Tensile test and SEM-EDS were carried out to investigate the tensile strength and appearence the intermetallic layer.The results of this study indicated that the highest value of tensile stresswas found on the use E7018 electrodes and 80 amperes electric current. While the lowest value was found in the use E6013 electrodes with 120 amperes. Intermetallic layer was detected base on the SEM-EDS investigation.

Arang daun bambu tutul sebagai kajian produk nanopartikel dan penghasil silica yang memiliki berbagai keunggulan dari segi sifat fisika dan kimia. Pada penelitian ini produksi nanopartikel menggunakan High Energy Milling (HEM) tipeshaker mill untuk memproduksi nanopartikel dari arang daun bambu tutul. Pada penelitian ini dilakukan uji PSA untuk menganalisa ukuran partikel, untuk menganalisa distribusi morfologi partikel dan komposisi kimia yang terkandung dalam material menggunakan uji SEM dan EDX. Siklus yang digunakan pada penelitian adalah 2 juta siklus dengan putaran motor listrik 1000 rpm, dan diameter bola baja 1/4 inchi. Tabung stainless steel berjumlah 4 dengan diameter tabung 2 inchi dan tinggi tabung 120 mm dengan perbandingan volume ruang kosong tabung yaitu 1:1, 1:2, 1:3, dan 1:4 dengan material. Penelitian ini bertujuan untuk mengetahui pengaruh volume ruang kosong tabung dan rata – rata diameter partikel, distribusi partikel, dan komposisi yang terkandung dalam partikel hasil tumbukan dengan alat shaker mill. Hasil penelitian ini menunjukkan bahwa volume ruang kosong tabung sangat berpengaruh pada mekanisme tumbukan. Dari uji PSA semakin besar volume ruang kosong tabung, semakin kecil ukuran partikel material yang dihasilkan. Hasil uji SEM dan EDX didapatkan unsur kimia karbon yang paling tinggi 68,47 % pada volume 1:1 ruang kosong tabung. Sehingga arang daun bambu tutul merupakan sumber potensi sebagai penghasil silica.

Garbage is a serious problem if it is not managed properly, both organic and non-organic. Inorganic waste, for example, plastic, metal, glass, and charcoal from coal combustion are difficult to decompose in the soil. HDPE (high-density polyethylene) plastic is one type of inorganic waste that is difficult to decompose, but this plastic can be recycled. The objective of the study is to develop light cement blocks by using the waste of HDPE, coal bottom ash and cement. The research guide was referred to SNI (Indonesian National Standard). The SNI-03-6825-2002 is for testing of the compressive strength and SNI 03-0349-1989 for the testing of the water absorption. The size of the specimen was 5 x 5 x 5 cm. In this study, the compositions of HDPE: coal bottom ash were varied by 70%: 0%, 60%: 10%, 50%: 20%, and 40%: 30%. The Holcim cement was 30% of the volume fraction. Testing was conducted after the specimens stay in 7 and 28 days. For the 7 days old of specimens, the highest compressive strength has resulted from 50%:20% composition with the value of 5.88 N/mm2. For the 28 days old specimens, the highest compressive strength was 8.34 N/mm2. The lowest water absorption test was delivered by the more coal bottom ash in the composition of 40%:30%. It was 16.971%. The more coal bottom ash, the less water absorption. The mean of specimens density was 1.076 gr/cm3. The result of the research shows that recycles HDPE and coal bottom ash as concrete block meet the required strength.

The Abaqus software was used to simulate the creep behavior of a cylindrical tube of Sanicro-25 austenitic steel under an internal pressure of 11.3 MPa at a uniform temperature at 750 °C. The data used for the simulation input were obtained from the experimental data of a previous work. The hidden information of material parameters was estimated from the shape of creep strain versus time plots obtained from the experimental data. The validated results between the simulation and the experimental data produced the material parameter of the creep power law which were set at 2.6 x 10-22 for the power law constant and 9 for the stress exponent. The parameters were further used to explore the stress and strain inside and outside of the tube wall and the thickness changes of the tube wall.

The purpose of this research is to investigate the corrosion resistance of 5052 aluminum alloy to increasing salinity in sea water. Salt spray chamber was used to measure and compare the corrosion rate of 5052 aluminum alloy with weight reduction method. The experiment was conducted by varying the three concentrations of NaCl solution to compare the corrosion rate of the metal. The test specimens used were aluminum alloy 5052 with length of 6 cm, width of 4 cm and thickness of 0.7 cm. The tests were carried out for 48 hours, aggressive NaCl solutions with concentrations of 3.5%, 4% and 5% were used as an artificial sea water corrosion medium and the temperature in the test chamber was maintained at 35 °C. Corrosion rate for 3.5% NaCl solution, 4% NaCl solution and 5% NaCl solution were 0.197 mm/year, 0.541 mm/year and 0.558 mm/year, respectively. The higher concentration leads to greater corrosion rate.

The residual stress generated after thin layer TiN coating by Physical Vapor Deposition is reducing the mechanical and tribological properties of TiN. Thermal stresses are one of the residual stress components which can cause failure modes of proper coatings. In this article, a validated computational simulation was developed to investigate the effect of physical and thermal properties on the thermal stresses of the coating, including the deposition temperature, Young's modulus of coating, the thermal expansion coefficient of coating, and the thicknesses of coating and substrate. An analytical method using Stoney & Tsui model was used to verify the simulation result by Abaqus software 6.14–5, and very good agreement was achieved. Results show that the thermal stress distribution is discontinued large difference between high stresses in the coating and low stress in the substrate. Also, increasing the deposition temperature from 100 oC to 500 oC increases the thermal stresses from 214 MPa to 1355 MPa linearly. Analysis of the coating thickness in the range of 1–5 µm slightly reduces the thermal stress from 1362 MPa to 1342 MPa, while an increase of the substrate thickness in the range of 1–5 mm increases the thermal stress from 1330 MPa to 1360 MPa. It is also realized that an increase in Young's modulus of TiN from 250 GPa to 600 GPa linearly increases the thermal stress from 567 MPa to 1355 MPa, while an increase of the coefficient of thermal expansion of TiN from 3.92×10−6 °C−1 to 9.40 × 10−6 °C−1 reduces the thermal stress from 3418 MPa to 1355 MPa.

The objective of the research was to propose a 90 degree steering mechanism system. The application of this steering system can be implemented on off-road cars, military vehicles, and city cars. The advantage of the systems is its flexibility in movement. Therefore, the vehicle will have high degree of moving in any direction. The mechanism was designed in 2D and 3D model. Subsequently, the components were joined in assembly and the kinematic simulation was done by using CATIA. Clash detection among the components was carried out in assembly workbench of CATIA. The results of this study will help the automotive industries to develop a real 90 degree steering system. All components were completely designed in 3D solid by using CATIA. Furthermore, the clash among the component in the product assembly could be eliminated by part editing. In the final assembly, none of the clash was detected.

The objective of the research is to design truck frame of 120 PS series. The method used in the research is reverse engineering, by re-designing the existing frames and taking its measurements. The measurement results are then used to design a frame in the CATIA V5 software. After the modeling, it will obtain the three-dimensional design in solid form. Static analysis was then performed to see the truck’s frame strength under the static load. The given loads vary from 8, 10, 12, and 16 ton. Based on the load, the maximum Von Mises stress results are 1.37 x 107 N/m2, 1.98 x 107 N/m2, 2.37 x 107 N/m2 and 3.16 x 107 N/m2 respectively. The maximum stress condition is still in the safe category based on comparison with the yield stress of steel material used of 2.5 x 108 N/m2. While the maximum strain that occurred at each loading was 0.025 mm, 0.0832 mm, 0.0999 mm and 0.133 mm, respectively.

Dissimilar welding of aluminum is an innovation used to increase the effectiveness and efficiency in making a product or component. It has been applied on the automotive industry, aerospace, and shipbuilding. Aluminum has low weldability in compared with steel material because of the oxide layer on the surface of aluminum. The welding problems of aluminum can be overcome by using a solid state welding such as friction stir welding (FSW). The objective of this study was to determine the strength of the welding joint and the microstructure of dissimilar welding joint with different series of aluminum. The tensile testing was performed with the weld directions of 0° and 45° to assess the formability, hardness testing, and microstructure of FSW. In this study, welding process was conducted to combine aluminum 1100 series (low strength aluminum) and aluminum 6061-T6 series (high strength aluminum) in the 2 mm thickness of aluminum sheet. The analysis was done by making comparison of the strength between dissimilar and similar aluminum series. The results showed that the dissimilar weld types, both in angle orientation of 0° and of 45° had fracture location on the HAZ area of 1100 aluminum series. The highest results of tensile strength were 78.07 MPa and 75.26 MPa for weld angle orientation of 0° and 45°, respectively. Weld angle orientation had significant effect to the strain where value of the welding direction of 0° was 10.99% and of 45° was 13.8%. Hardness test in the weld zone generated diverse values because the material stirring was not homogenous, whereas the similar welding was more stable in the welding area. Microstructure investigation on the dissimilar aluminum welding found a hook defects in the weld nugget. In the HAZ area, the grain size of 6061-T6 increased while of 1100 material decreased. It might be affected by the temperature and the aluminum characteristic. Meanwhile, in weld nugget, the grain size increased due to the stirring tool joint and heating during the welding process.

The objective of the research is to design the outer rear door of Esemka Rajawali 2 by using reverse engineering method. Esemka car is one of the national cars being developed in Indonesia. Esemka Rajawali 2 has a Sports Utility Vehicle (SUV) model with 1.6L engine version, 1,597 cc inline DOHC. Reverse engineering method is used to obtain geometry data from the existing products and to reconstruct into three-dimensional drawing model. The three-dimensional model is used to design the mold or dies. Dies design is done by using CATIA V5 software. The process of die making plays an important role because it will be produced with a variety of car body components with particular desired shape. Design of a car body consists of various models, shapes, and construction. After the mold designs are completed, static analysis was done to determine the stresses that occur in the mold. This research has succeeded in modeling a three-dimensional model of the rear door using reverse engineering method. The dies design was successfully created using CATIA V5 software. From the static analysis results, by employing a maximum load of 50,000 N, the mold is still in a safe condition based on the yield stress of the used material.

In this paper, a dynamic explicit method was used to simulate U-bending processes of aluminium and its springback. The simulation was carried out using a free software of finite element analysis code namely Impact. The model was taken from a benchmark model in Numisheet'93. The numerical results of the dynamic explicit code were compared with the results of the experimental works. After the optimization was done using the simulation process, it was found that the springback results showed a good agreement with that done by the experimental results. The software Impact was capable of simulating the U-bending processes and predicting the occurrence of springback.

Tailored welded blank (TWB) consists of steel sheets of different thicknesses and strength which welded into one sheet to reduce weight and production costs, to increase dimensional accuracy and strength. Since a tailored blank is composed of different sheets of metals having different thicknesses and properties, the forming of tailored blanks then creates a lot of technical problems especially in the scheme of deformation. The objective of this work was to evaluate the drawability of tailored blanks. In order to assess the forming behavior of the tailor-welded blanks under the influence of weld orientations, a finite element and experimental methods were conducted. Three welded specimens with weld lines oriented at an angle of 0°, 90° and 45° with respect to the direction of load were investigated. The finite element result showed in a good agreement with the experimental result. The result of the experiment showed that a welded part was characterized by a higher strength and lower plasticity compared to those of the base material. Hence, the weld influences the strain distribution of the tailor-welded specimens. This phenomenon depends strongly on the direction of the weld against the direction of tensile load. The lowest strains occur in the specimen with a longitudinal weld.

The objective on this research is to investigate the influence of tool rotation to the welding strength of Aluminium and Steel. AA1100 and ST37 were material selected for the specimens. The welding process was conducted by using Friction Stir Welding (FSW) method. The tensile strength and hardness of the specimens will be indicators of welding strength. FSW was carried out by using conventional milling machine with tool rotation of 800 rpm and 1250 rpm. Feed rate 10 mm/minute for all process. The tool tilt angle was 1° and 1.8 mm of depth plunge. By using 800 rpm, the average of Tensile Stress was delivered of 82.22 MPa and Strain of 1.09%. While for the use of 1250 rpm, Tensile Stress given 96.23 MPa and Strain 1.14%. The hardnes of HVN on the weld zone was 42.2 and 56.2 HVN for rotation of 800 and 1250 rpm respectively. Based on the Tensile Stress and the Hardness of the weld zone, the FSW process was influenced by tool rotation. The higher rotation given higher Tensile strength.

The existence of fossil fuels is increasingly scarce nowadays. Therefore, finding alternative fuels to substitute petroleum fuels, especially gasoline that very huge used for a motor vehicle. One of the alternative fuels as a substitute for gasoline is bioethanol (BE). The aim of the research work was to analyze engine performance and exhaust emission level of vehicle using two different types of spark plug. Further investigation was addressed by varying additional bioethanol fuel made from raw material of cassava. The work was carried out experimentally both in the laboratory and engine test drive. The results show that by using platinum spark plug resulting better performance of engine. The additional bioethanol on fuel, the power, and torque generated from the engine increases with the increase of percent bioethanol in the fuel mixture. The fuel consumption is more efficient by using fuel of 30% BE, compared with engine operation using fuel of 100% pertalite. While the results of the exhaust emission on the vehicle show that by using fuel bioethanol, exhaust emissions decrease as the increase of bioethanol in fuel mixture than exhaust emissions generated when using fuel 100% pertalite. It was proved by statistical data analysis using a one-way ANOVA Varian (F test) for power, torque, and HC emission levels, found of F value less than F table. Therefore hypothesis null (Ho) was accepted. Further result in each variation of fuel there is no significant difference. However, for CO, found that counted F greater than F table, then Ho was rejected; therefore the result of each variation of fuel there is significantly different.

Manufacturing of beverage cans is porcessed by using multi-stage ironing following deep drawing from the sheet material of aluminum and steel. An earing profiles are develops during deep drawing of cylindrical cup due to the planar anisotropic properties of sheet. Therefore, the analysis of earing is important to evaluate and control the development of earing. This paper describes a simulation of the cold ironing process in the forming cylinder cap. The ironing process in this study was focused on the prediction of height increasing, earing and thinning. Two different materials of aluminum AA5042 and AKDQ steel were selected for comparison. The results show that the increasing of cup height was in the same trend.

Numerical simulation by finite element method has become a powerful tool in predicting and preventing the unwanted effects of sheet metals technological processing. One of the most important problems in sheet metal forming is the compensation of springback. To improve the accuracy of the formed parts, the die surfaces are required to be optimized so that after springback the geometry falls at the expected shape. This paper presents and discusses numerical simulation procedure of die compensation by using the methods of Simplified Displacement Adjustment (SDA). This analysis use Benchmark 3 models of Numisheet 2011. Sensitively analysis was done by using finite element method (FEM) show that the springback values are influenced by element size, integration points and material properties.

In commercial aerospace development, feasibility accidents design or crashworthiness is a major concern in aviation safety. Fuselage structure plays an important role in absorbing energy during an accident. The research aims are to determine drop test phenomenon on the fuselage, to investigate deformation occurred in the structure of the fuselage, and to know the influence of the airframe falls position to the stress strain which occurred in the structure of the fuselage. This research was conducted by varying the fall angle of the fuselage in a vertical position or 0° and 15°. Fuselage design was modeled by using SolidWorks. Then the model is imported to the Abaqus for drop test simulation. From the simulation results, it can be obtained the phenomenon of deformation on the structure of the fuselage when it comes in contact with the rigid ground. The high deformation occurs shows the structure capabilities in order to absorb the impact. It could be happened because the deformation is influenced by intern...

Plastic injection merupakan proses manufactur untuk membuat produk dengan bahan dasar plastic atau dalam kesempatan ini polypropylene. Pada proses tersebut seringkali terjadi cacat produk seperti pengerutan, retak, dimensi tidak sesuai dan kerusakan saat produk keluar dari mould, sehingga banyak material yang terbuang percuma. Meskipun cacat produk tersebut dipengaruhi banyak factor, tetapi yang paling utama adalah masalah shrinkage, atau penyusutan material setelah terjadi pendinginan. Sangat penting untuk melakukan prediksi lebih awal terjadinya penyusutan setelah pendinginan untuk menghindari cacat produk. Dalam penelitian ini akan dilakukan prediksi shrinkage yang akan digunakan untuk material polypropylene dengan cara perhitungan standar. Pembuatan modeling dalam bentuk 3D (tiga dimensi) injection molding baik cavity maupun corenya dengan menggunakan CATIA, kemudian dilakukan analisis dengan software MoldFlow untuk pembuatan mesh dan memberikan batasan panas pada komponen sehingga dapat diketahui mode penyusutannya. Analisis ini akan memberikan gambaran tentang distribusi panas pada mould dan memberikan tentang gambaran aliran fluida. Pada analisis tersebut dapat dilihat gejala terjadinya cacat produk, jika hal itu terjadi maka perlu dilakukan perubahan shrinkage, sampai diperoleh hasil analisis yang baik.

The objective on the research was to investigate the mechanical properties and microstructure of tailor welded blank (TWB) made from AA6061-T6 and AA1100 using friction stir welding (FSW) process. Due to the dissimilar mechanical properties of the two aluminium alloys, microhardness test was conducted to measure the hardness distribution across the weld nugget. The mixing of two distinct materials was influenced by tool rotation speed. Therefore, microstructure analysis was carried out to investigate the grain size and shape. The grain size of AA6061-T6 has increased in the heat affected zone (HAZ) while for AA1100 has decreased. In the weld nugget, it has found a hook defects in the dissimilar aluminium joining. By using monotonic tensile load, the different weld line direction was observed with the expansion in tool rotation. The joints failure were consistently on the area of AA1100 series. Furthermore, two specimens were investigated, one through the dissimilar aluminium and the other through similiar material. Inspection of the weld nugget hardness was shown that nonhomogen material intermixing during the stiring process as confirmed by microhardness measurement.

The most key factor in the modern sheet metal process is an accurate dimension of final shape part. The accurate simulation of the drawing products will not be useful since springback will occur after the tools are removed off the drawing die set. One of the most promising ways to solve this problem is modify the die surface as known die compensation. Die compensation is one of the hottest topics in the stamping field. In this paper, a new method to compensate the die tool shape due to elastic deviation is proposed. The combination of spring-forward and spring-back method is applied simultaneously. This method was applied to 2D draw bending benchmark problem from Numisheet '93 for verification. The simulation result show that the final deformed part is closely to the desired shape part.

Springback phenomenon theoretically occurs for anything kind of deep drawing or sheet metal forming process. In the real manufacture, it is a well known and avoided characteristic of every process that involves plastic deformations on elastic metals. To improve the accuracy of the formed parts, the die surfaces are required to be optimized and compensate therefore after springback the geometry falls at the expected shape. The proposed procedure combined two methods of die compensation; Displacement Adjustment Method (DAM) and Spring‐forward method (SFM) of Karafillis and Boyce (K&B) called Hybrid Method (HM). Both are based on iteratively comparing the deformed shape with the target. According to the advantages of each method DA and K&B to solve the springback compensation problem, these methods are applied alternately. This paper presents and discusses the proposed framework in accommodating springback in sheet metal forming.

An accurate modelling of the sheet metal deformations including the springback prediction is one of the key factors in the efficient utilisation of Finite Element Method (FEM) process simulation in industrial application. Assuming that springback can be predicted accurately, there still remains the problem of how to use such results to appear at a suitable die design to produce a target part shape. It is this second step of springback compensation that is addressed in the current work. This paper presents an evaluation of a standard benchmark model defined as Benchmark II of Numisheet 2008, S-channel model with various drawbeads and blank holder force (BHF). The tool geometry modified based on springback calculation for a part to compensate springback. The result shows that the combination of the smooth bead with BHF of 650 kN resulted in the minimum springback and the tool compensation was successfully to accommodate the springback errors.