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Pemodelan Desain Sol Sepatu dengan Inovasi Penambahan Wave Spring Bintara, Redyarsa Dharma; Kharismaningtyas, Puspita Fajar; Choiron, Moch. Agus; Purnowidodo, Anindito
Jurnal Energi Dan Manufaktur Vol 7 No 2 (2014): Oktober 2014
Publisher : Department of Mechanical Engineering, University of Udayana

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Abstract

Desain sepatu sport berkembang pesat dengan tujuan mengurangi cedera dan meningkatkankenyamanan pengguna. Pengurangan cedera dilakukan dengan cara memperbesar energi yangdiserap dari beban akibat pengguna berlari atau melompat. Pada penelitian ini dilakukanpenambahan wave spring yang digunakan sebagai mekanisme penyerap beban.Pemodelandilakukan pada sol sepatu dengan menggunakan bantuan software finite element method (FEM)Ansys 14.5 Academic. Model awal dilakukan untuk mengetahui batas deformasi sol sepatu yangakan dimanfaatkan sebagai input model berikutnya yaitu model dengan diberikan inovasipenambahan wave spring. Analisa difokuskan pada sol sepatu bagian belakang (tumit kaki).Darihasil simulasi, didapatkan bahwa penyerapan energi sol sepatu dengan penambahan wave springlebih besar daripada penyerapan energi sol sepatu tanpa penambahan wave spring, sehinggapenambahan wave spring memungkinkan untuk diaplikasikan pada sol sepatu sport.Kata kunci: Penyerapan energi, wave spring, sol sepatu.Sport shoe design had been developed rapidly with the purpose to reduce injuries and increaseuser comfort. Reduction of injury is done by enlarging the energy absorbed from the user running orjumping load. In this study, the addition of the wave spring is used as the load absorbingmechanism. The shoes sole is modeled by using finite element method (FEM) software Ansys 14.5Academic. Initial model was conducted to determine the deformation boundary in soles which willbe used as input to the next model for the wave spring addition innovation. Analysis focused onshoe sole on heel foot. From the simulation results, it was found that the energy absorption shoessoles with the addition of the wave spring is greater than the energy absorption soles without theaddition of wave spring. It can be concluded that the addition of a spring wave can be applied to thesoles of sports shoes.Keywords: Energy absorb, wave spring, shoe sole, deformation boundary
KARATERISTIK MAKRO DAN MIKRO PLAT BAJA-ALUMINIUM TERHADAP KETAHANAN BALISTIK Purwanto, Helmy; Soenoko, Rudy; Purnowidodo, Anindito; Suprapto, Agus
Prosiding SNST Fakultas Teknik Vol 1, No 1 (2015): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 6 2015
Publisher : Prosiding SNST Fakultas Teknik

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Abstract

Pengembangan material tahan balistik atau peluru tidak hanya pada material baja, tetapi mengarah pada material yang mempunyai massa jenis ringan. Aluminium merupakan alternatif material yang dapat diaplikasikan dalam kontruksi tahan balistik. Perpaduan kekerasan dan keuletan menjadi salah satu faktor untuk menahan laju peluru yang dikeluarkan dari senapan. Pembuatan panel ganda berlapis (layer) aluminium-baja atau baja-aluminum dilakukan untuk mengetahui ketahanan balistik dengan menggunakan peluru kaliber 5,56 x 45 mm (MU5-TJ) yang ditembakkan dari jarak 15 m. Aluminium cair dituang pada plat baja ketebalan 6 mm hingga menjadi satu-kesatuan plat ganda berlapis dengan metode squeeze casting. Hasil pengujian balistik menunjukkan panel aluminum-baja dan baja aluminium tidak dapat tertembus peluru walaupun terjadi penurunan kekerasan plat baja karena proses panas pada saat pengecoran. Lapisan yang lebih keras di sisi muka mempunyai ketahanan balistik yang lebih  optimal dibandingkan dengan lapisan yang lebih lunak pada sisi depan dari arah laju peluru. Kata kunci: plat berlapis, pengecoran squeeze, ketahanan balistik
Pengaruh Mechanical Bonding pada Aluminium dengan Serat Karbon terhadap Kekuatan Tarik Fiber Metal Laminates Firmansyah, Hilmi Iman; Purnowidodo, Anindito; Setyabudi, Sofyan Arief
Rekayasa Mesin Vol 9, No 2 (2018)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (877.239 KB) | DOI: 10.21776/ub.jrm.2018.009.02.9

Abstract

Fiber metal laminates (FML) are composite structures fabricated by combining two layers of surface material with the core material. The outer surface of FML used in this composite is Aluminum with Al 1100 type. The FML core material uses carbon fiber. The fabrication process of the composites utilizes vacuum infusion method, in which the resin is infused into the mold with a vacuum condition. Bonds between the core and the surface layers are the variables affecting the strength of FML. In this research, the method used to increase the bonds between layers in FML was a mechanical method, it?s called mechanical bonding. This method involved providing roughness (Ra) on the aluminum surface using sandblasting process to produce different roughness variables, with roughness value of 1,68 ?m; 1,78 ?m; 1,93 ?m; 2,128 ?m and 2,887 ?m. The aim of this study was to examine the effect of aluminum surface roughness to the tensile strength of fiber metal laminates composites. The highest tensile strength of FML was obtained at 2,887 ?m with a value of 367 MPa.
Analisa Kegagalan pada Spindle Mesin Batch Centrifugal Purnowidodo, Anindito; Wahjudi, Ari; Prawira, Riza
Rekayasa Mesin Vol 2, No 1 (2011)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

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Abstract

Failure analysis was conducted on the failure shaft of batch centrifugal. In the analysis the stress analysis was used to know the stress distribution, and in conjuction with stress analysis the life time of the component can be estimated. In addition, the fractography anlaysis together with mechanical properties test were carried out to understand the mechanism of the failure. With respect to the result of analysis shows that the failure was caused by fatigue crack initated on the surface of shaft due to the inhomogeneus mechanical properties, in this case, the hardness is lower than that on sub surface of the shaft. Besides that, the stress concentration was found take place on the surface of shaft on which the crack was initated. Further, it was known that during machining process, the material of shaft was heated on elevated temperature on the surface to ease the process. The heating reduced the hardness as well as the strength of the material.Keywords : Failure, Fatigue, Crack.
Hubungan Diameter Pasak, Lubang Sambungan Dan Ketebalan Plat Terhadap Distribusi Tegangan Sisa Wahjudi, Ari; Purnowidodo, Anindito; Pambudi, Wijil
Rekayasa Mesin Vol 2, No 3 (2011)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

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Abstract

The discontinuities on the structures or members are often to be encountered such as, rivet and bolt holes as well as notches. These discontinuities are agents for stress raiser and itcan initiate cracks in the vicinity of holes or in the notch roots. It is well known that most of the fatigue failure is caused by cracks growth initiated from the discontinuities. To reduce possibilitythe initiation of crack in those stress raisers, the compressive residual stress, in general, is imposed to the region in which the stress concentrates. In the present study, using expansionhole technique carried out by aid of computer simulation, the effect of mandrel diameter and thickness of the blank to the residual stress in the vicinity of the hole is investigated. The result shows that the magnitude of the residual stress in the vicinity of the hole varies depending onthe magnitude of the expansion and the thickness of blank. In addition, in the certain distancefrom the hole, the tensile residual stress develops, hence, it may endanger a component because it causes the crack growth rate increase, as consequent, the life time of a componentis shorter.Keyword: mandrell diameter, hole diameter, thickness, residual stress distribution
Pengaruh Temperatur Pelat Landasan Selama Proses Friction Stir Welding Terhadap Kekuatan Tarik Sambungan Las Lembaran HDPE Setiawan, Agus; Irawan, Yudy Surya; Purnowidodo, Anindito
Rekayasa Mesin Vol 2, No 3 (2011)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

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Abstract

The purpose of this study was to determine the weld ability of HDPE sheets (High Density Polyethylene) through the method of welding FSW (Friction Stir Welding). FSW is a new welding process, where joined of the material occurs in the solid state. Samples were welded with vertical milling CNC machines, while the type of connection is a butt joint. This study used three process parameters, two parameters are combined and one parameter value is constant, the parameters combined are temperature backing plate (30; 70; 110 and 150 oC) and the welding tool rotation speed (2200; 2300 and 2400 rpm), while the parameters with constant value is the welding speed (30 mm / min). In this research experiment conducted observations and analysis of surface textures welded joints, weld surface temperature during the process in front of and behind the welding tools, macro-structure of the welded joints, the maximum tensile strength and fracture tensile test results. From the results of this study was obtained that temperature backing plate during FSW process affects the maximum tensile strength and homogeneity of HDPE sheets welded joints. The maximum tensile strength of welded joints higher is 28.52 MPa or 95.07% of the maximum tensile strength of HDPE material, the maximum ultimate tensile strength values were obtained on the condition temperature backing plate t = 150 oC and the welding tool rotation speed n = 2300 rpm. Heating the material HDPEby backing plate during FSW process insulator properties of the material that is an obstacle inthe process of forming a perfect weld can be resolved.Keyword: temperatur backing plate, friction stir welding, the tensile strength of welded joints,HDPE sheets.
Pengaruh Parameter Proses Incremental Backward Hole-Flanging terhadap Ketebalan Kerah pada Alumunium 1050A Fakhruddin, Muhammad; Choiron, Moch. Agus; Purnowidodo, Anindito
Rekayasa Mesin Vol 10, No 1 (2019)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.jrm.2019.010.01.4

Abstract

Conventional hole-flanging process in a small batch is sometimes costly or almost impossible due to the variety of the product profile. Recent studies showed that modern manufacturing was developed to overcome the limitation of the conventional hole-flanging process. Incremental backward hole-flanging (IBHF) was one of the strategies that developed to overcome this particular limitation. The main objective of this research was to investigate the influence of IBHF process parameters toward collar thickness of the product. It enables to measure the impact and behavior of each process parameters, i.e., forming speed, axial and radial forming step size toward the particular response parameter. The result showed that axial and radial forming step size was the main influence and the forming speed has a slight effect towards collar thickness. The behavior of each parameter was increased forming speed and radial forming step size would decrease collar thickness, whereas increased axial forming step size would increase collar thickness.
Distribusi dan Interaksi Tegangan Sisa antar Lubang Setelah Proses Cold Expansion Hole Wahjudi, Ari; Purnowidodo, Anindito; P, Andika H
Rekayasa Mesin Vol 3, No 3 (2012)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

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Abstract

It is well known that the main cause of a failure of structure is initiated by cracks on a member. A crack may originate easily in a region with high stress concentration. Because in the rivet and the bolt joining method are usual with number of holes, and to reduce the stress concentration, the compressive residual stress is introduced in the region near by the hole. The cold expansion hole technique is used to developed compressive residual on the vicinity of the edge hole. The present study was carried out by the computer simulation based on finite element method to investigate the distribution and interaction residual stress in the region between holes related to the cold expansion hole. The result of the study suggests that the distance between holes influence the state of residual stress and its magnitude. These cause by the deformed material between holes interact each other.Keywords: residual stress distribution, stress interaction, region between holes
Analisis Fatigue Failure Suhu Rendah Struktur Batang Duralumin dengan Mesin Siklus Bending Tawaf, Nanang; Suprapto, Wahyono; Purnowidodo, Anindito
Rekayasa Mesin Vol 5, No 3 (2014)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

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Abstract

Generally non-iron metals use in industries, including aluminum alloy, because of their high strength to weight ratio and favorable (no sparking and high corrosion resistance). Aluminum alloy are often found and used in airplane. Recently, aluminum alloy begins so popular in cryogenic system where it is highly applied at oil industry, low temperature operated, and automotive industry. It is estimated that 50%-90% mechanical failures are due to fatigue failure. This research attempts to predict duralumin fatigue resistance at low temperature and to understand the effect of micro structure on duralumin at low temperature. Several states, which include 15, 30, and 45 in MPa, are given to bending cycle machine. The tested material is duralumin (alloy Al-Cu) which has passed the tests over porosity, fatigue level at low temperature (-19o C) and room temperature (27o C), microstructure, fractography, and macrostructure. Result of research indicates that fatigue resistance increases with lowering work tense at specimen. Average fracture of duralumin fatigue at low temperature is more than 17,8 x 10 cycles, while at room temperature is 13 x 10 5 cycles. During low temperature fatigue test, microstructure shows long and small grains. The deformation during low temperature fatigue test cause smaller grain produce greater slip resistance for specimen.Keywords: Fatigue Failure, Low Temperature, Duralumin, Bending Cycle
Perilaku Rambat Retak di Daerah Lubang yang Terekspansi pada Aluminium Alloy Syahrizal, Syahrizal; Purnowidodo, Anindito; Soenoko, Rudy
Rekayasa Mesin Vol 5, No 1 (2014)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

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Abstract

Mechanism of crack propagation is done by loading the cycle against the perforated metal material will be difficult to avoid, to fatigue crack growth rate can be a way to expand its peg with the hole that normally uses metal balls as an alternative. By using a materials testing machine type cantilever bending eccentric crank, life time of the materials are determined. Research using the method of cold expansion hole in the aluminum alloy metal material to a hole with a diameter of 5 mm in expansion using pin with variation of  5,1 mm,  5,15 mm and  5,2 mm made that crack found on the side of the hole would be difficult to propagate due to residual stress comparison. The result shows that there are residual stresses around the hole which varies depending on the diameter of the pin. In addition, there is growing tensile residual stress within a certain distance of the specimen being tested resulted in a faster growth rate, this causes the material usage time will be shorter.Keywords: cold expansion hole, materials testing machine, aluminumalloy, comparison residual stress, life time.