Mikrofabrikasi Jalur PCB Menggunakan Metode Visible Ligth Maskless Photolitography

Pada tulisan ini akan dibahas metode modifikasi dari Photolitography yaitu Visible Ligth Maskless Photolitography, perbedaannya menggunakan sinar tampak (visible light) dan tanpa mask (cetakan) selanjutnya diaplikasikan pada fabrikasi jalur listrik PCB (printed circuit board). [DI1]Kelebihan metode adalah mudah, murah tetapi mampu membuat profil rumit dan aman. Cara kerjanya model/ profil dibuat di komputer/ laptop kemudian dipancarkan melalui DLP projector. Pada bagian bawah projector dipasang PCB yang sudah dilapisi Negative Photoresist sehingga terjadi proses exposure. Selanjutnya dilakukan proses developing dan eching sehingga terbentuk profil sesuai desain. Pada jenis projector Infocus IN114A ditemukan parameter terbaik: posisi lensa pemfokus pembesaran 3X berjarak 3 cm dibawah DLP projektor dan 14 cm diatas material uji PCB, menggunakan kombinasi warna hitam (R:0 G:0 B:0) dan biru terang (R=0, G=176, B=240) dengan waktu prebake 2 menit, spin 2.000 rpm, exposure 3 menit, developing 5 menit, Postbake 5 menit dan Eching 5 menit. Profil jalur listrik yang berhasil dibuat diantaranya: garis, huruf, alur listrik, dan bentuk microcontroller. Hasil pengukuran Scanning Electron Microscope (SEM) profil garis terkecil yang dapat dibuat yaitu m132 m dan memiliki kekasaran tepi (deviasi) 6,6 m

ANALISIS DAMPAK GAYA TUMBUKAN MELALUI PERUBAHAN BENTUK SEGI CRUSH INITIATOR PADA STRUKTUR TAILOR-WELDED BLANK

Tailor-welded blank (TWB) structure is one of the vehicle component models used in vehicle parts. In addition, these structures can be used in crashworthiess technology which can reduce injuries during a collision.. The structure of a vehicle that has greater strength can cause passengers to be thrown from the passenger compartment. This paper discusses the effect of faceted holes such as square, hexagonal and octagonal as crush initiator mounted on TWB which results in a maximum impact force (Fmax). The smallest maximum impact force is the criteria achieved from this study. The method used experimental quasi-static loading of the actuator speed of 0.5 mm/s to achieve 9.5 mm of deformation. TWB was made from plate formation with a process of stamping to spot weld. The result showed that the maximum impact force has an increase directly proportional to the addition of the shape of the crush initiator in the amount of 14.633 kN to 18.705 kN. From these results, it can be seen a square hole as best design in obtaining the smallest maximum impact force

Multiobjective optimization of dimension and position of elliptical crush initiator on crashworthiness performance of square tube using response surface methodology

In this study, the crashworthiness performance of a thin-walled square steel-tube structure with an elliptical crush initiator under impact loading was investigated. The effect of the height, width, and distance of the crush initiator from the top of the tube on the crashworthiness performance was analyzed using several numerical simulations using ABAQUS Explicit. The response surface methodology was used to predict the crashworthiness performance indices, and optimization was performed to determine the optimal dimensions and position of the crush initiator. The optimization was aimed at minimizing the peak force (PF) while maximizing the mean crushing force (MCF), crush force efficiency (CFE), and specific energy absorption (SEA). The result was an elliptical crush initiator with a height of 15 mm, width of 24.784 mm, and distance of 15.08 mm. Validation was performed to verify these results. The optimal crush initiator effect resulted in a 10.12% decrease in the peak force, 13.67% increase in the crush force efficiency, and 2.23% increase in the mean crushing force. However, a slight decrease of 0.82% in specific energy absorption was observed

Realization of Photo-curing Gelatin Hydrogel using a Commercial Projector for Culturing Mesenchymal Cells

This paper investigates the realization of synthetic extracellular matrix with visible light photo-patterning gelatin in a simpler manner. A synthetic extracellular matrix provides an initial attachment for the seeded cells on the experimental substrate such as glass plate or multi-well until they realized their the natural extracellular matrix. Here, a commercial Digital Light Projector (DLP) was used to induce gelatin with Rose Bengal as a crosslinking agent to form the thin layer on the experimental substrate. Various gelatin concentrations from 2%-10% were exposed at different times in order to optimize the patterning process. A geometrical characterization on the patterned gelatin, such as contour measurement and resolution, were taken place. Results showed that the thickness of patterned gelatin was in the range of 10 µm – 60 µm depends on the exposure time of the DLP projector. Moreover, a visual method aided by the Fiji toolbox from NIH ImageJ image processing was used to observe the density and spatial arrangement of the cultured cells on the substrate. Ultimately, biocompatibility using MTT assay was also employed to confirm the viability of the cells on the gelatin substrate. The results show that we are able to control the physical and spatial arrangement of the gelatin substrate, and they with cell viability depend on 6 days of observation. It was found that the gelatin substrate provides faster growth on cultured cells compared to the control study. This finding leads to the possibility to realize the automation system in cell culture technology with an affordable investment

Theoretical Prediction of Dynamic Axial Crushing on a Square Tube with Eight Holes Used as a Crush Initiator

Thin-walled square steel tubes are part of automobile structures, used as impact energy absorbers on crush boxes. Under axial crushing, such tubes sometimes produces unpredictable folding forms. There are three modes of dynamic axial crushing folding forms: the symmetric collapse mode; the asymmetric mixed collapse mode A; and the asymmetric mixed collapse mode B. The objective of this paper is to develop a theoretical prediction for the three modes on a thin-walled square steel tube with eight holes used as crush initiator. The basic folding mechanism is used to predict the dynamic axial crushing analysis on the tube. These theoretical analyses can also can be implemented in different crush initiator positions. Two types of cross section (c/h) were used in this study: specimen A (c/h = 60.42) and specimen B (c/h = 45.69). Thirty-six experimental drop test studies were conducted on the thin wall square tube. In addition, the results of a previous drop test were compared to the results of the theoretical prediction. The results show that the theoretical analysis has good agreement with the experimental drop test study. This study proposes nine formulas to predict average force, peak force and energy absorption of the dynamic axial crushing on the thin-walled square steel tube with eight holes of crush initiator. The limitation of these formulas, however, is that they are unable to show the relationship between force and time in a graph

Dry Film Photoresist Application to a Printed Circuit Board (Pcb) using a Maskless Photolithography Method

This paper offers an alternative method of making PCB routing using a negative dry film photoresist and a maskless photolithography method. The objective of this research is determining the correct parameters for the process of making PCB design easier, cheaper and safer. Electronic circuit design was created on a laptop or PC using Autodesk EAGLE software with a combination of result is black and blue light color. PCB routing design was inserted into a PowerPoint slide to display on a commercial Digital Light Processing (DLP) projector. No modifications were made to projector, which was mounted directly on a stand with a downward facing position. The projector lamp replaced an ultraviolet or X-ray source during the exposure process, exposing PCB coated in negative dry film photoresist. After the exposure process, the PCB was inserted into developer solution, causing the blue light irradiated part to remain while the blackened sections dissolved. The PCB was then added to an etching solution to scrape the copper unprotected by the photoresist. The PCB was finally soaked in a remover solution to remove the photoresist. Once complete, the process generated a laptop-designed PCB routing. Electrical lines can be created using this method with a size of 100 µm and a lane edge deviation of 5 µm. The goal of research to make PCB routing cheaper, easier and safer was achieved. Evidenced by the installation of electronic components and then tested, the results are all components function well

FLEXIBLE-DIE FORMING SHEET-METAL MENGGUNAKA N PERANTARA TEKANAN VISKOPLASYIK

Abstrak Pada-proses pembentukan lembaran logam, yang lebih dikenal dengan sheet-metal forming, biasanya, perantara -tekanan yang digunakan berupa bahan padat, cair, atau gas.- Banyak kekurangan-kekurangan yang dimiliki pada penggunaan bahan yang telah disebutkan di alas. Dari berbagal percobaan yang telah dilakukan oleh para peneliti, salah satu jenis bahan pengganti perantara tekanan: yang digunakan adalah bahan viscoplastik Pada makalah inl akan dikemukakan beberapa jenis proses sheet-metal forming yang menggunakan. bahan perantara tekanan viscoplastik Akan ditunjukkan beberapa kelebihan proses ini dan embar teknik rancangan peralatannya. Kata kunci: forming, sheet-metal, voskoplastik, die, tekanan Abstract Sheet-metal forming is forming processes using a solid, liquid or gas as a medium pressure. Any disadvantage are in this process, mainly with conventional medium as told before. Many experience wich done by researhes medium viscoplastic is beter than solid, liqiud and gas mudium. This paper discus kind sheet-metal forming processes uses viscoplastic as amediunt. This paper will show advantage of this process and technical drawing of it's design.Hal. 83-88: ilus.; 24,5 c

Pengembangan Pengujian Crashworthiness dengan Simulasi Numerik Menggunakan Model Impact Transferability

Collision test is needed in transportation area in order to anticipate injuries of passangers when the accident occurred. Therefore, this test must be done for achieving standar requirements which is known by crashworthiness. This paper discussed about development of crasworthiness test by using modelling impact transferability by numerical simulation. The goal is to know the error of maximum deformation when given axial dynamic loading between numerical simulation and real experiment. Furthermore, analitic was used to validate duration of stress wave propagation from result of numerical simulation. This simulation used explicit finite element method by using PAM-Crash. The component of this research was impactor and impact of transferability with 80 and 27 kg of mass. The square tube-thin walled structure with holes as crush initator 3 mm of diameter was used as specimen. The result shows maximum deformation and duration of stress propagation error which are 3.90 % and 14.89 %.

Effect of Infill Pattern on Impact Toughness, Microstructure, and Surface Roughness of Inconel 625 Built via Filament-Based Material Extrusion Additive Manufacturing

Filament-based material extrusion additive manufacturing (FMEAM) is an additive manufacturing technique that uses 3D printing. Additive manufacturing could build parts with infill variations. Solid or triangular infill pattern could be selected as needed. The solid pattern will have the maximum material volume, while the triangular pattern will contain a triangular lattice structure that fills the voids in the volume so the material requirement is reduced. This is valuable in optimizing the requirements of metallic materials for mechanical properties without changing the surface shape. The alloy Inconel 625, which is very popular in the aerospace industry have been developed as a feed material of FMEAM. However, for developing rotating parts, such as turbine blades, impact toughness, surface roughness and microstructure need to be investigated. This research was conducted to determine the effect of the infill pattern on the impact toughness, morphology of surface fracture, microstructure of side surface and surface roughness with Inconel 625 material built using FMEAM. The Charpy impact test, s ASTM 23, with v-notch testing method and SEM with EDS were performed. The results showed that the impact toughness for solids was higher than the value for the triangular infill pattern. It was discovered that the cavities in the triangular lattice structure within the specimen reduced the impact toughness to 57.6%. Micropores and residual polymer trapped on the surface reduce impact toughness. However, the same surface shape on solid and triangular infill patterns with surface roughness of 2.44 and 10.03 µm is still feasible for manufacture

Non Machinable Volume Calculation Method for 5-Axis Roughing Based on Faceted Models through Closed Bounded Area Evaluation

The increase in the volume of rough machining on the CBV area is one of the indicators of increased efficiencyof machining process. Normally, this area is not subject to the rough machining process, so that the volume of the rest of the material is still big. With the addition of CC point and tool orientation to CBV area on a complex surface, the finishing will be faster because the volume of the excess material on this process will be reduced. This paper presents a method for volume calculation of the parts which do not allow further occurrence of the machining process, particulary for rough machining on a complex object. By comparing the total volume of raw materials and machining area volume, the volume of residual material,on which machining process cannot be done,can be determined. The volume of the total machining area has been taken into account for machiningof the CBV and non CBV areas. By using delaunay triangulation for the triangle which includes the machining and CBV areas. The volume will be calculated using Divergence(Gaussian) theorem by focusing on the direction of the normal vector on each triangle. This method can be used as an alternative to selecting tothe rough machining methods which select minimum value of nonmachinable volume so that effectiveness can be achieved in the machining process