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Banten
INDONESIA
Metalurgi
Published by BRIN Publishing
ISSN : 01263188     EISSN : 24433926     DOI : 10.55981/metalurgi
The objective of this journal is the online media for disseminating results in Research and Development and also as a media for a scientist and researcher in the field of Metallurgy and Materials. The scope if this journal related on: Advanced materials and Nanotechnology Materials and Mineral characterization and Analysis Metallurgy process: extractive Ceramic and composite Corrosion and its technological protection Mineral resources manifestation Modelling and simulation in materials and metallurgy Engineering Metallurgy instrument
Articles 287 Documents
PREPARASI, SINTESIS DAN KARAKTERISASI MATERIAL OKSIDA Ca3Co4O9 [Preparation, Synthesis and Characterization Of Ca3Co4O9 Oxide Material] Sigit Dwi Yudhanto
Metalurgi Vol 30, No 1 (2015): Metalurgi Vol.30 No.1 APRIL 2015
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (466.35 KB) | DOI: 10.14203/metalurgi.v30i1.107

Abstract

Penelitian dilakukan untuk membuat material oksida Ca3Co4O9 dengan menggunakan proses reaksi padat. Material oksida Ca3Co4O9 merupakan material termoelektrik yang mempunyai kestabilan yang baik dan sudah banyak diaplikasikan. Bahan baku sintesis Ca3Co4O9 adalah serbuk CaO dan CoCO3. Proses pembuatan diawali dengan penimbangan bahan baku, dilanjutkan dengan penggerusan, kalsinasi, kompaksi dan sintering. Pelet disinter pada suhu 700, 750, 800, dan 850°C ditahan selama 24 jam dengan kondisi atmosfir udara. Pola difraksi sinar-x menunjukkan bahwa mayoritas puncak pantulan adalah fasa Ca3Co4O9. AbsractThe study was conducted to make Ca3Co4O9 oxide material using solid state reaction process. Ca3Co4O9 oxidematerial is a thermoelectric material that has good stability and has been widely applied. The raw materials areCaO and CoCO3 powders. Synthesis process begins with the weighing of raw materials, followed by grinding,calcination, compaction and sintering. Samples sintered at temperatures 700, 750, 800, dan 850°C for 24 hoursin air atmospheric conditions. X-ray diffraction pattern shows that the majority of the reflection is Ca3Co4O9phase.
Pengaruh Suhu Dan Persentase Reduksi Terhadap Limit Drawing Ratio (LDR) Pada Proses Metal Forming Paduan 70Cu-30Zn [Effect of Temperature and Reduction Percentage to Limit Drawing Ratio (LDR) on Metal Forming of 70Cu-30Zn Alloy] Amin Suhadi; Eka Febriyanti; Tri Handayani; Rini Riastuti
Metalurgi Vol 31, No 2 (2016): Metalurgi Vol. 31 No. 2 Agustus 2016
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (769.499 KB) | DOI: 10.14203/metalurgi.v31i2.126

Abstract

In metal forming, LDR parameter determination has an important role on the quality of the product.  Therefore, characteristic data such as load bearing capacity limit of material should be known prior to the metal forming process. In this research, 70Cu-30Zn alloy with 70% Cu and 30% Zn which is widely done in metal forming especially deep drawing is used as samples.  The samples are warm rolled at various temperatures and reduction percentages and then deep drawn by swift cup method based on ASTM E 643-15.  To find LDR value,  further analysis are done by  FEM (finite element method) simulation and calculation for swift cup result based on formula as stated in ASTM E 6431-15 standard. Characterization is conducted by hardness test and micro structure examinations.  Result of this reseach show that the LDR value is not significantly affected by reduction percentage but strongly affected by working temperature, where the highest temperature of metal forming has been given, the highest limit drawing ratio (LDR) could be obtained. AbstrakPenentuan nilai parameter LDR (limit drawing ratio) pada proses metal forming sangat berpengaruh terhadap kualitas produk, karena itu sebelum melakukan proses pengubahan bentuk diperlukan data mengenai batas kemampuan dari logam untuk menerima gaya pada proses tersebut. Pada penelitian ini digunakan paduan Cu- Zn dengan komposisi 70% Cu dan 30% Zn yang banyak dipakai pada proses pengubahan bentuk terutama deep drawing. Paduan 70Cu - 30Zn dilakukan proses warm rolling pada berbagai suhu dan persentase reduksi, kemudian dilakukan uji deep drawing dengan metode swift cup sesuai standar ASTM E 643-15. Untuk mencari nilai LDR, dilakukan simulasi menggunakan FEM (finite element method) dan perhitungan hasil swift cup dengan rumus sesuai stadar ASTM E 643-15. Karakterisasi yang dilakukan adalah pengamatan struktur mikro dan uji keras. Hasil dari penelitian menunjukkan bahwa nilai LDR tidak dipengaruhi oleh % reduksi tetapi sangat dipengaruhi oleh suhu saat pengerjaan dilakukan, dimana makin tinggi suhu proses metal forming, makin tinggi nilai LDR akan dihasilkan.
SINTESIS DAN KARAKTERISASI MEMBRAN KOMPOSIT KITOSANHIDROKSI APATIT BERIKATAN SILANG SEBAGAI GUIDED TISSUE REGENERATION (GTR)[Synthesis and Characterization of the Chitosan (Cs)-Hydroxyapatite (Ha) Crosslinked Composite Membrane for Guided Tissue Regeneration (GTR)] Errizal errizal; Basril A; Yessy W; Darmawan Darmawan
Metalurgi Vol 28, No 1 (2013): Metalurgi Vol.28 No.1 April 2013
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (576.184 KB) | DOI: 10.14203/metalurgi.v28i1.246

Abstract

Deposisi Lapisan Fe-Si-Al-Mg pada Baja Karbon dengan Teknik Pemaduan Mekanik [Deposition of Fe-Si-Al-Mg Coatings Using Mechanical Alloying Technique] Lusita Lusita; Riser Fahdiran; Toto Sudiro; Bambang Hermanto
Metalurgi Vol 34, No 1 (2019): Metalurgi Vol. 34 No. 1 April 2019
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (579.136 KB) | DOI: 10.14203/metalurgi.v34i1.465

Abstract

Fe-Si-Al-Mg coatings by weight variation of ferrosilicon, Mg, and Al as 50(Fe-Si)-37.5Al-12.5Mg, 50(Fe-Si)-25Al-25Mg, and 50(Fe-Si)-12.5Al-37.5Mg have been prepared on low carbon steel substrate using the mechanical alloying technique. The coatings were studied using XRD (x-ray diffractometer) to comprehend the phase formed on the substrate and OM (optical microscopy) to measure the coating thickness. Based on XRD and OM characterization, Fe-Si-Al-Mg coatings were successfully deposited on the low carbon steel substrate. Fe-Si-Al-Mg layers are composed by intermetallic phases of FeSi2, Mg2Si, and Al0.7Fe3Si0.47. Each composition shows different coating thickness that tends to decreases with the increase of magnesium concentration and the reduction of aluminum concentration. AbstrakLapisan Fe-Si-Al-Mg dengan variasi berat ferrosilicon, Mg dan Al yaitu 50(Fe-Si)-37.5Al-12.5Mg, 50(Fe-Si)-25Al-25Mg, dan  50(Fe-Si)-12.5Al-37.5Mg telah dipreparasi pada substrat baja karbon rendah dengan menggunakan teknik pemaduan mekanik (mechanical alloying). Struktur dari lapisan Fe-Si-Al-Mg dipelajari menggunakan XRD (X-ray Diffraction) untuk mengetahui fasa yang terbentuk dan OM (Optical Microscope) untuk mengetahui ketebalan lapisan yang didapatkan. Hasil X-ray Diffraction dan Optical Microscope menunjukkan bahwa lapisan Fe-Si-Al-Mg telah berhasil dideposisikan pada substrat baja karbon rendah. Lapisan Fe-Si-Al-Mg yang terbentuk memiliki fasa intermetalik FeSi2, Mg2Si dan Al0.7Fe3Si0.47. Setiap komposisi menunjukkan ketebalan lapisan yang berbeda. Ketebalan lapisan cenderung menurun dengan meningkatnya konsentrasi magnesium dan berkurangnya konsentrasi aluminium.
PENGARUH BAHAN PEREKAT DAN WAKTU REDUKSI PADA PEMBUATAN BRIKET SPONGE DARI BIJIH BESI LOKAL[Effect of Binder and Reduction Time in The Preparation of Sponge Iron Briquette from Local Iron Ore] Adil Jamali; Fiqa Rofiq Mufakhir; Muhammad Amin
Metalurgi Vol 27, No 2 (2012): Metalurgi Vol. 27 No. 2 Agustus 2012
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (317.212 KB) | DOI: 10.14203/metalurgi.v27i2.146

Abstract

PENGARUH UKURAN BUTIRAN TERHADAP STRUKTUR KRISTAL PADA PROSES KALSINASI PARSIAL DOLOMIT [Effect of Particles Size to Crystal Structure in Partial Calcination Process of Dolomite] eko sulistiyono
Metalurgi Vol 30, No 3 (2015): Metalurgi Vol. 30 No. 3 Desember 2015
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (338.326 KB) | DOI: 10.14203/metalurgi.v30i3.71

Abstract

Salah satu proses yang menentukan pada pembuatan magnesium karbonat adalah proses kalsinasi mineral dolomit. Dari proses kalsinasi ini akan diketahui apakah terjadi pembentukan senyawa MgO, CaO, CaCO3dan MgCO3 . Pada proses kalsinasi diharapkan untuk dapat membentuk senyawa MgO dalam jumlah banyak dan CaO dalam dalam jumlah sedikit. Pada tahapan proses selanjutnya diharapkan MgO yang terbentuk menjadi magnesium bikarbonat mampu larut dalam air dan kalsium berada dalam bentuk CaCO3 yang tidak larut dalam air.  Pada penelitian ini telah dilakukan percobaan kalsinasi dolomit dari Gresik  dengan variabel ukuran butiran, temperatur dan waktu proses. Dari hasil percobaan diketahui bahwa dolomite dari Gresik memiliki titik kalsinasi parsial antara temperatur 600ºC sampai dengan temperatur 700ºC dan kalsinasi total antaratemperatur 800ºC sampai dengan temperatur 900ºC. Semakin besar ukuran butiran proses kalsinasi semakin cepat, dimana ukuran butiran paling besar yaitu 2,5 cm menunjukkan hasil yang paling cepat. Sehingga titik optimal ukuran butiran belum ditemukan oleh karena itu percobaan dengan ukuran butiran diatas 2,5 cm dengan skala percobaan lebih besar dari 100 gperlu dilakukan. AbstractOne of the processes that determine the magnesium carbonat production is calcination process in dolomitmineral. From that process can be known that MgO, CaO, CaCO3 and MgCO3 happened. On calcinationprocess expected that MgO can be formed in large quantities and CaO in small quantities. On the next stepexpected that MgO which was formed as Mg(HCO3)2 soluble in water and calcium which was formed asCaCO3 not dissolved in water. This research has been done a calcination process on dolomite mineral fromGresik and used three variables such as particles size, temperature and time of this process. From the result ofthis research were known that the dolomite from Gresik has a partial calcination point around 600 °C until700 °C, total calcination around 800 °C until 900 °C.The result also shows that the particles size effected thetime of calcination, when its size reached 2.5 cm the calcination time was the fastest. But the optimal resultwas not found yet so that the particles size above 2.5 cm and the scale of the research above 100 g need to bedone.
Pengaruh Rapat Arus dan Waktu Pelapisan Nikel pada AISI 410 dengan Metode Pulse Electrodeposition terhadap Strukturmikro dan Laju Korosi [The Influences of Current Density and Time on Microstructure and Corrosion Rate Nickel Coating in Aisi 410 by Pulse Electro Deposition Method] Rivaldo Ramadhana Saputra; Soesaptri Oediyani; Yulinda Lestari; Efendi Mabruri
Metalurgi Vol 32, No 2 (2017): Metalurgi Vol. 32 No. 2 Agustus 2017
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (312.31 KB) | DOI: 10.14203/metalurgi.v32i2.224

Abstract

Nickel plating process with pulse methods in AISI 410 electrodepostion has been done to reduce corrosion rate of this material in industrial applications i.e turbine blade that is often experienced corrosion problems. The coating process using nickel sulfate 250 g / l, boric acid 50 g / l and nickel chloride 45 g / l at temperature of 50-60 ° C with various of current densities for 10, 15, 20 and 25 A / dm² and time for coating process of 10, 15 and 20 minutes. Duty cylce used was 80% and the pulse frequency approximately around 100 Hz. Microstructure examined by using SEM-EDS (scanning electron microscopy-energy dispersive spectroscopy) to observe grain size and thickness of the nickel layer. Corrosion rate measured by using CMS (corrosion measurement system).  The results showed that increasing of current density and coating process would reduce grain size and corrosion rate in coating area. The corrosion rate is 0.00027 mmpy when the current density is 25 A / dm² and plating time is 20 minutes. AbstrakProses pelapisan nikel dengan metode pulse electrodepostion pada AISI 410 dilakukan untuk menurunkan laju korosi AISI 410 pada aplikasi industri, yaitu turbin blade yang sering mengalami masalah korosi. Proses pelapisan menggunakan larutan nickel sulphate 250 g/l, boric acid 50 g/l dan nickel chloride 45 g/l pada temperatur 50 – 60°C dengan variasi rapat arus 10, 15, 20 dan 25 A/dm² dan lamanya proses pelapisan 10, 15 dan 20 menit. Duty cylce yang digunakan adalah 80% dan frekuensi pulse 100 Hz. Pengujian struktur mikro dilakukan menggunakan SEM-EDAX untuk melihat ukuran butir dan ketebalan lapisan nikel yang terbentuk. Pengujian laju korosi dilakukan menggunakan alat CMS. Hasil penelitian menunjukkan bahwa semakin besar rapat arus dan semakin lama proses pelapisan maka ukuran butir yang tergambarkan dalam mikrostruktur lapisan semakin kecil dan laju korosi yang terukur semakin kecil. Laju korosi paling kecil adalah 0,00027 mmpy pada rapat arus 25 A/dm² dan waktu pelapisan 20 menit.
The Effect of Voltage and Time In Synthesis Manganese Dioxide from Manganese Sulfate Precursor Eka Fitri Wulandari; Lia Andriyah; Soesaptri Oediyani; Latifa hanum Lalasari; Tri Arini; Nadia Chrisayu Natasha; Fariza Eka Yunita; Ariyo Suharyanto; Eko Sulistiyono
Metalurgi Vol 37, No 1 (2022): Metalurgi Vol. 37 No. 1 April 2022
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (582.192 KB) | DOI: 10.14203/metalurgi.v37i1.599

Abstract

The utilization of manganese dioxide (MnO2) as a cathode material for lithium-ion battery has attract many attentions because of their excellent electrochemical properties which have high theoretical storage capacity of 615 mAh/g. In this study, synthesis of MnO2 was carried out from manganese sulfate (MnSO4) precursor which is a pregnant leach solution from the leaching process of manganese ore from Trenggalek Regency. The electrolysis method has been used in this synthesis of MnO2 in an electrochemical cell consisting of two graphite electrodes with dimensions (16 x 5 x 0,3) cm. The purpose of this study is to determine the effect of voltage and time to particles amount of MnO2, to determine the phase and crystal structure of MnO2 and its morphological microstructure. The electrolysis process was carried out in 2000 ml of MnSO4 solution under constant stirring at 60oC with DC voltage varied by 2, 4, 6 and 8 volt and time varied by 4, 8, 12 and 16 hours. The precipitates formed at anode were separated, then the particles were dried at 110oC for 2 hours. The main contain of MnO2 were analyzed by X-Ray Fluorescence (XRF), the phase and crystal structure were evaluated by X-Ray Diffraction (XRD) and the morphological microstructure were captured by Scanning Electron Microscope (SEM). The results revealed that the highest particles amount of MnO2 is 31,63 grams which is electrolyzed at 8 volts for 16 hours. The highest purity of MnO2 is 89,23% which is electrolyzed at 2 volts for 16 hours. The particles produced were α-MnO2 with a tetragonal crystal system and nearly spherical in shape with size particles ranged from 136,01-202,48 and 144-352 nm.
KONSENTRASI PASIR BESI TITAN DARI PENGOTORNYA DENGAN CARA MAGNETIK Dedi Sufiandi
Metalurgi Vol 26, No 1 (2011): Metalurgi Vol. 26 No. 1 April 2011
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (301.972 KB) | DOI: 10.14203/metalurgi.v26i1.4

Abstract

Pasir besi titan Indonesia cadangannya cukup besar terutama di daerah sekitar pantai Selatan Jawa. Salah satu potensi pasir besi titan yang akan di teliti adalah pasir besi dari daerah Tegal Buleud Pantai Selatan Sukabumi. Pemanfaatan pasir besi titan merupakan alternatif yang diperlukan untuk memenuhi kebutuhan bahan baku industri baja yang dalam perkembangan dan kebutuhannya semakin meningkat dengan terbatasnya cadangan bijih  besi  konvensional.  Tujuan  penelitian  untuk  mendapatkan  kualitas  pasir  besi  titan  yang  memenuhi persyaratan  peleburan,  perlu  dilakukan  konsentrasi untuk  meningkatkan  kadar  besi  dengan  cara  magnetik. Metode percobaan adalah melakukan identifikasi pasir besi titan dengan mengunakan analisa XRD. Kemudian dilakukan proses preparasi sampel dan pengayakan sebelum dimasukan kedalam peralatan pemisah magnetik dan  dari  pemisah  magnet  akan  dihasilkan  produk  konsentrat,  middling,  dan  tailing.  Hasil  percobaan menunjukkan produk konsentrat pasir besi titan mempunyai kandungan Fe2 03   80 % dan TiO2   20 %. Dan pemisahan pasir besi titan dengan kondisi optimum diperoleh pada kondisi arus 3,5 ampere dan fraksi - 100 mesh dengan perolehan konsentrat rata-rata 90 %. AbstarctTitan iron sand has been found a lot in Indonesia especially around west coast of Java. One of titan iron sand used in this research is iron sand from Tegal Buleud area at Sukabumi west coast. The utilization of iron sand is an alternative to fill-up the rising demand of raw material for steel industry development due to limited amount of conventional iron ore. To obtain the quality of titan iron sand which is suitable with the requirement for smelting, it is needed to have concentration process by magnetic separator to increase iron content. The step of experiment were identification of titan iron sand composition, preparation of sample and sampling processes, and material separation using magnetic separator to get concentrate, middling, and tailing products. The result of experiment shown concentrate product of titan iron sand has Fe2O3 and TiO2 with weight composition 80 % and 20 % respectively. And also The optimum condition in magnetic separator was 3.5 Ampere current and fraction -100 mesh got average concentrate yield about 90 %.
PENGARUH OIL SPILL DISPERSANT TERHADAP KOROSI PADA STRUKTUR BAJA KONSTRUKSI DI LINGKUNGAN AIR LAUT Rahardjo Binudi; Sundjono Sundjono
Metalurgi Vol 29, No 2 (2014): Metalurgi Vol.29 No.2 Agustus 2014
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (461.865 KB) | DOI: 10.14203/metalurgi.v29i2.284

Abstract


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