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Gedung Manajemen Puspiptek Gedung 720, Jl. Puspitek, Muncul, Kec. Setu, Kota Tangerang Selatan, Banten 15314, Tangerang Selatan, Provinsi Banten, 15314 Alamat Penerbit : Gedung BJ Habibie, JI. M.H. Thamrin NO. 8, Kb. Sirih, Kec. Menteng, Jakarta Pusat, Provinsi DKI Jakarta, 10340, Tangerang Selatan, Provinsi Banten
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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
Failure of Heat Exchanger Return Bend Due to Long-Term Localized Overheating [Kerusakan pada Pipa Belokan U Alat Penukar Kalor akibat Panas Berlebih secara Lokal dalam Jangka Panjang] Dewa Nyoman Adnyana
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 (1138.848 KB) | DOI: 10.14203/metalurgi.v34i1.463

Abstract

A return bend of a heat exchanger had failed due to bursting after it had been only about 2.5 years in service. The heat exchanger was used to transfer heat from hot combustion gas on the shell side to the feedstock oil on the tube side. Type and factors that may have caused the return bend bursting are discussed in this paper. The metallurgical assessment was conducted by preparing a number of specimens from the as-received burst and unburst return bends. Various laboratory examinations were performed including visual and macroscopic examination, chemical analysis, metallographic examination, hardness testing, and scanning electron microscopy equipped with energy-dispersive spectroscopy analysis. Results of the metallurgical assessment obtained showed that the burst return bend had been experiencing fracture overload due to local hot spot or long-term localized overheating occurred on the outer bend external surface. The long-term localized overheating was most likely caused by formation of fouling deposit that was built up on the outer bend internal surface, leading to increase the corrosion rate significantly and resulted in excessive metal loss or thinning occurred on the outer bend external surface. Consequently, the hoop stress at the outer bend section had been increasing significantly and eventually the working pressure of the feedstock oil on the tube side could burst the return bend wall thereonAbstrakTulisan ini menyajikan penelitian yang dilakukan pada sebuah belokan pipa U (return bend) pada sebuah alat  penukar kalor yang mengalami kerusakan (pecah) setelah beroperasi hanya dalam waktu 2,5 tahun. Alat penukar kalor tersebut digunakan untuk memindahkan panas dari gas panas hasil pembakaran pada sisi bejana/tabung ke  dalam bahan baku minyak (feedstock oil) pada sisi pipa. Material belokan pipa U tersebut dibuat dari baja karbon dengan standar ASTM A-234 Gr.WPB, memiliki diameter 2 inch dan tebal SCH 80. Penelitian berupa observasi dan pengujian metalurgi dilaksanakan dengan menyiapkan sejumlah sampel material dari belokan pipa U, baik yang sudah pecah maupun yang tidak pecah. Pengujian yang dilakukan meliputi uji visual dan makro, analisa kimia, uji metalografi, uji kekerasan dengan metoda Vickers dan SEM (scanning electron microscopy) - EDS (energy dispersive spectroscopy).  Hasil pengujian metalurgi menunjukkan bahwa pipa belokan U yang pecah mengalami kerusakan akibat beban berlebih yang dipengaruhi oleh local hot spot atau panas berlebih secara lokal dalam jangka panjang (long-term localized overheating). Akibatnya, tegangan yang bekerja pada dinding belokan pipa U mengalami peningkatan yang sangat signifikan sehingga pada akhirnya tekanan operasi yang terjadi pada bahan  baku minyak di dalam  pipa dapat merobek atau memecahkan bagian dinding belokan pipa U tersebut.
MODEL OFF-LINE UNTUK SIMULASI PROSES PEMURNIAN BAJA DI VACUUM TANK DEGASSER (VTD) [Off-Line Model for Refining Steel Process Simulation in Vacuum Tank Degasser (VTD) Zulfiadi Zulhan
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 (1030.546 KB) | DOI: 10.14203/metalurgi.v27i2.145

Abstract

STUDI PERILAKU PELINDIAN BIJIH NIKEL LIMONIT DARI PULAU HALMAHERA DALAM LARUTAN ASAM NITRAT [Study on the Leaching Behaviour of Limonite Nickel Ore From Halmahera Island in Nitric Acid Solution] Mohammad Wildanil Fathoni; Mohammad Zaki Mubarok
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 (598.092 KB) | DOI: 10.14203/metalurgi.v30i3.42

Abstract

pelindian bijih nikel laterit maupun meregenerasi reagen pelindi menjadi fokus perhatian peneliti dan dunia industri dalam beberapa tahun belakangan ini. Salahsatu teknologi yang dikembangkan adalah pelindian bijih nikel laterit asam nitrat, dimana >95% asam nitrat yang digunakan dapat diregenerasi kembali. Pada paper ini didiskusikan perilaku pelindian bijih nikel laterit yang diperoleh dari Pulau Halmahera dalam larutan asam nitrat. Serangkaian percobaan pelindian dalam larutan asam nitrat telah dilakukan dengan variasi konsentrasi asam nitrat, persen padatan dan temperatur. Analisis ekeperimental faktorial desain 23 digunakan untuk mempelajari pengaruh variabel temperatur, konsentrasi asam dan persen padatan serta interaksi antara variabel-variabel tersebut dalam proses pelindian. Hasil percobaan menunjukkan bahwa ekstraksi Ni tertinggi yaitu 94% diperoleh pada pelindian selama 8 jam dengan konsentrasi asam 6M, 10% padatan dan temperatur 95°C. Variabel yang paling berpengaruh pada ekstraksi Ni adalah temperatur dengan persen kontribusi mencapai 78%. Selektivitas (S) pelindian Ni terhadap Fe dan Mg relatif rendah, dengan nilai rata-rata SNi/Fe dan SNi/Mg masing-masing 0,53 dan 0,50. Konsumsi asam cukup tinggi, dimana konsumsi tertinggi pada temperatur 95°C, konsentrasi asam 4M dan 10% padatan yaitu 1010 kgh./ton biji. AbstractEfforts to reduce the consumption of leaching agent either by increasing selectivity of nickel laterite oreleaching and regeneration of the leaching agent, are being the focus of researchers and industries in recentyears. One of technologies that is developed is the leaching of laterite ore in nitric acid, through which morethan 95% of nitric acid being used can be regenerated.In this paper, leaching behavior of nickel laterite orefrom Halmahera Island is discussed. A series of leaching experiments in nitric acid solution has been carriedout under variations of nitric acid concentration, solid percentage and temperature. Analysis usingexperimental factorial design of 23 was performed to determine the effects of temperature, acid concentrationand solid percentage as well as the interaction between these variables toward nickel extraction duringleaching. The experimental results show that the highest nickel extraction of 94%, was obtained from theleaching test for 8 hours using acid concentration of 6 M, 10% solid at temperature of 95 °C. The mostinfluencing variable on nickel extraction is temperature with contribution of 78%. Selectivity of Ni leachingto Fe and Mg is relatively low, with average values of SNi/Fe and SNi/Mg of 0.53 and 0.50, respectively.Acid consumption in leaching process is relatively high, which the highest consumption was at leachingtemperature of 95°C, acid concentration 4 M and 10% solid, namely 1010 kg/ton ore.
Studi Awal Sintesis dan Karakterisasi Bi(Pb)-Sr-Ca-Cu-O dengan Penambahan Carbon Nanotube dan TiO2 Menggunakan Metoda Reaksi Padatan dan Proses Sintering Berulang [Preliminary Study Synthesis and Characterization of Bi(Pb)-Sr-Ca-Cu-O By Addition of Carbon Nanotube and TiO2 Using Solid Reaction Method and Recurrent Sintering Process] Rizki Syahfina; Bintoro Siswayanti; Sigit Dwi Yudanto; Agung Imaduddin; Nurul Suhada; Fauzan Amri; Mukti Hamjah Harahap
Metalurgi Vol 32, No 3 (2017): Metalurgi Vol. 32 No. 3 Desember 2017
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (571.06 KB) | DOI: 10.14203/metalurgi.v32i3.330

Abstract

Bi1.6Pb0.4Sr2Ca2Cu3O10+δ with the addition of carbon nanotubes (CNT) and TiO2 have been synthesized using solid state reaction method with the repeated sintering process. 0.1 wt % of CNT and 5 wt% of TiO2 have been added to analyze the effect on the synthesizing of 2223 phases. The samples were analyzed using XRD (X-ray diffractometer) and SEM (Scanning Electron Microscopy). Based on the XRD results, 2223 and 2212 were formed. The addition of CNTs and TiO2 reduced the intensity of 2223 phases. This is due to the addition of CNTs and TiO2 as an impurity and prevent the formation of the phases. Also, the repeated sintering process led to the increase of 2223 phase, and the decrease of 2212 phase. However, the repeated sintering process in the B-CNT and B-TiO samples eliminates the impurities phase thus increasing the volume fraction 2223 and decreasing the volume fraction 2212. Based on morphological structure through SEM observation, the addition of CNT in the Bi(Pb)-2223 samples formed longer plates with large porosity spaces while the addition of TiO2 formed clumps on the Bi(Pb)-2223 morphological structure. However, the repeated sintering process improves the morphological structure of B-CNT and B-TiO becomes increasingly denser and the smaller porosity space.AbstrakTelah dilakukan sintesis Bi1,6Pb0,4Sr2Ca2Cu3O10+δ dengan penambahan CNT (carbon nanotube) dan penambahan TiO2 menggunakan metode reaksi padatan dengan proses sintering berulang. Penambahan CNT sebesar 0,1 %berat dan TiO2 sebesar 5 %berat dan sintering berulang dilakukan untuk mempelajari pengaruhnya terhadap pembentukan fasa 2223 beserta pengotornya, dan mempelajari perubahan morfologi Bi1,6Pb0,4Sr2Ca2Cu3O10+δ. Bi1,6Pb0,4Sr2Ca2Cu3O10+δ yang dibuat dianalisis dengan XRD (x-ray diffractometer) dan SEM (scanning electron microscopy). Berdasarkan hasil XRD, penambahan 0,1 %berat CNT dan TiO2 sebesar 5 %berat pada superkonduktor Bi(Pb)-2223 diketahui menghasilkan fasa 2223, fasa 2212, dan juga fasa pengotor. Namun proses sintering berulang mampu mengurangi fasa impuritas, meningkatkan fraksi volume 2223, serta menurunkan fraksi volume 2212.   Berdasarkan pengamatan struktur morfologi melalui SEM, penambahan CNT pada superkonduktor Bi(Pb)-2223 membentuk serpihan memanjang dengan ruang porositas yang besar sedangkan penambahan TiO2 membentuk gumpalan pada struktur morfologi Bi(Pb)-2223. Proses sintering berulang mampu memperbaiki struktur morfologi B-CNT dan B-TiO menjadi semakin rapat dan ruang porositas yang semakin kecil. 
EFFECTIVENESS OF THE SEPARATION OF MAGNESIUM AND LITHIUM FROM SEAWATER WITH SODIUM SILICATE PRECIPITATION PROCESS Latifa Hanum Lalasari; Eko Sulistiyono; Sri Harjanto; Florentinus Firdiyono; Nadya Chrisayu Natasha; Yosephin Dewayani
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 (572.608 KB) | DOI: 10.14203/metalurgi.v37i1.640

Abstract

Experiments have been carried out to separate elements of magnesium and lithium from seawater to produce a lithium concentrate product that is free of magnesium through sodium silicate precipitation processes. In this study, the sample used was seawater taken from the Ancol Lagoon Area, North Jakarta. The sea water used contains 0.1674 ppm lithium ions and 1761 ppm magnesium ions with a high Mg/Li ratio of 10521. The seawater containing high levels of magnesium is not suitable as a raw material for for the manufacture of lithium carbonate (battery active ingredient) prior to initial processing. The research variable was the volume of sodium silicate solution added by 10 ml, 20 ml, 30 ml, 40 ml, 50 ml, 60 ml, 70 ml, and 100 ml which were equivalent to 13%, 27% 40%, 53%, 67%. , 80 %, 93%, and 107% stoichiometry of magnesium ion and the technique of adding sodium silicate solution included a single stage and multi-stages. From the experimental results, it can be seen that the most effective addition of sodium silicate is the addition of 80% stoichiometry. The sodium silicate precipitation process succeeded in separating magnesium ions and lithium ions from seawater as indicated by a decrease in the Mg/li ratio from 10521 to 64. The obstacle in this study was that there were still many lithium ions that were also precipitated with magnesium silicate during the precipitation process so that the lithium lost in the filtrate reached 82.26% in the single stage process. Therefore, a multi-stage process was carried out with 6 stages of the process that the addition of sodium silicate for each stage was 1/6 of the volume of sodium silicate solution at single stage optimum conditions. The results obtained from the multi-stage process were able to reduce the lithium ion lost in the filtrate to 76.54%. From the results of the study, it can be concluded that efforts to reduce the percentage of lithium ions lost in the filtrate product need to be carried out through the development of a sodium silicate precipitation process.
KENDALA DAN KEMUNGKINAN PENGEMBANGAN PROSES CARON UNTUK BIJIH NIKEL LATERIT KADAR RENDAH INDONESIA Arifin Arif
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 (161.866 KB) | DOI: 10.14203/metalurgi.v26i1.3

Abstract

Bagian terbesar dari bijih nikel laterit Indonesia yang cadangannya lebih dari 1 milyar ton termasuk pada klasifikasi bijih berkadar rendah. Komposisi bijih kadar rendah tersebut sangat bervariasi, dari bijih saprolit yang tinggi kandungan oksida magnesium dan silikatnya serta bijih limonit yang tinggi kandungan oksida besi dan aluminiumnya. Selain itu bijih limonit juga berpotensi mengandung silikat yang cukup tinggi. Oleh karena itu selalu ada kemungkinan dari suatu cebakan bijih, kandungan total magnesium dengan aluminium dan atau silikat dari bijih campuran tersebut masih melampaui dari batas kritis olahan proses HPAL. Oleh karena itu pengolahan optimal tidak dapat diharapkan hanya dari proses HPAL. Seperti diketahui walaupun kinerjanya tinggi tetapi proses HPAL cocok hanya untuk bijih yang kandungan magnesium dan atau silikatnya rendah seperti limonit murni. Untuk itu perlu disiapkan alternatif berupa proses yang komposisi bijih umpannya dapat lebih fleksibel. Kalau pilihannya adalah proses Caron tampaknya masih diperlukan langkah pendekatan terhadap beberapa kendala yang harus dihadapi oleh proses tersebut bila akan dikembangkan kedepan. AbstarctThe largest portion of more than 1 billion ton Indonesian nickel laterite ore deposits can be classified as low grade. It is informed that the compositions of the ores varies in wide range, with high magnesium oxide and silicates contents for saprolite and high iron and aluminium oxides for limonite. The limonit ores are also potential in containing high enough silicate. Due to it always possible that the total magnesium and aluminium and or silicates contents of the mixed ores deposits are higher than the ore feed compositions critical limits of HPAL, so it is predicted that the optimal treatment would not be achieved if based only on HPAL process. As have been known even HPAL is high in performance but just only suitable for certain ores with low magnesium and low silicates contents such likes pure limonite. For that it requires to provide alternative processes which are more flexible toward ore feed compositions. If the selected process is Caron, still it needs some steps of problems approach that have to be faced for the future process development.
ANALISIS KERUSAKAN TUBE THERMOCOUPLE PADA REAKTOR HYDROCRACKING DI KILANG PENGOLAHAN MINYAK BUMI Hadi Sunandrio
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 (1095.79 KB) | DOI: 10.14203/metalurgi.v29i2.283

Abstract

Pengaruh Proses Perlakuan Panas terhadap Nilai Kekerasan Metal Matrix Composite Coating pada Substrat SS316 untuk Aplikasi Pipa Boiler [The Effect of Heat Treatment Process on Hardness Value of Metal Matrix Composite Coating on SS316 Substrate for Boiler] erie martides
Metalurgi Vol 33, No 3 (2018): Metalurgi Vol. 33 No. 3 Desember 2018
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (607.698 KB) | DOI: 10.14203/metalurgi.v33i3.432

Abstract

Deposition of MMC (metal matrix composite) Coating of NiCr+Cr3C2+Al2O3 and NiCr+WC12Co+Al2O3 on the surface of SS316 material for coal fire boiler application have been performed using HVOF (high velocity oxygen fuel) technique with constant  parameters of fuel pressure and spray distance  After that the MMC layers are heated with temperature variation of 600, 700 and 800 °C with water quenched to obtain optimum hardness value according to the application of boiler tube of power plant. The highest hardness value applied to the NiCr+WC12Co+Al2O3 layer with the heat treatment process of 800 °C ie. 551.31 VHN AbstrakDeposisi lapisan komposit dalam matriks logam (MMC) NiCr+Cr3C2+Al2O3 dan NiCr+WC12Co+Al2O3 pada permukaan material SS316 untuk aplikasi pada pipa boiler batu bara telah dilakukan menggunakan teknik HVOF (high velocity oxygen fuel) thermal spray coating dengan parameter tekanan bahan bakar dan jarak penembakan yang konstan. Selanjutnya lapisan MMC dipanaskan dengan variasi temperatur 600, 700 dan 800 °C dan pendinginan menggunakan air untuk mendapatkan nilai kekerasan yang optimum sesuai dengan aplikasi pada pipa boiler pembangkit listrik. Nilai kekerasan yang tertinggi diperoleh pada lapisan NiCr+WC12Co+Al2O3 dengan proses perlakuan panas 800 °C yaitu sebesar 551,31 VHN.
FENOMENA DYNAMIC STRAIN AGING PADA PROSES TEMPA PANAS PADUAN Co-33Ni-20Cr-10Mo[Dynamic Strain Aging Phenomena of Co-33Ni-20Cr-10Mo Alloy During Hot Forging] Ika Kartika
Metalurgi Vol 27, No 1 (2012): Metalurgi Vol. 27 No. 1 April 2012
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (877.426 KB) | DOI: 10.14203/metalurgi.v27i1.136

Abstract

A Preliminary Study of Cobalt Solvent Extraction from Nickel Sulphate Solution Using Organic Extractant-PC-88A Subagja, Rudi; Rohman, Arief Dwi; Milandia, Anistasia; Oediyani, Soesaptri; Setiawan, Iwan
Metalurgi Vol 38, No 1 (2023): Metalurgi Vol. 38 No. 1 2023
Publisher : National Research and Innovation Agency (BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (625.14 KB) | DOI: 10.55981/metalurgi.2023.684

Abstract

In present study, a solvent extraction experiment has been done to separate cobalt from the nickel sulfate solution by using 2-ethythexyl phosponic acid mono-2-ethylhexyl ester (PC-88A) as extractant. The experiment was carried out on a laboratory scale by using a separating funnel to extract cobalt from the nickel sulfate solution with PC88A. The mixed solution was shake in separating funnel for a specified period of time, and after the solvent extraction experiment was finished the organic phase PC88 was separated from the nickel sulfate solution by decantation. The nickel and cobalt content in the aqueous nickel sulfate solution were then analyzed using Atomic absorption spectrophotometry (AAS). In this experiment, the variable for  experiments were covering  solution pH from 2 to 6, shaking time from 30 minutes to 120 minutes, shaking speed  from 20 revolutions per minute (rpm) to 80 rpm, and the volumeratio  of aqueous to organic phase  (A:O ratio) was from 1:1  to 1:4. The effects that experimental variables to the cobalt extraction were observed in this experiment. The result of experiment at room temperature, solution pH 5, shaking speed  60 rpm,  shaking time  90 minutes,  A:O ratio  1:4 and  concentration of PC- 88A  40% show  97.21% of cobalt can be extracted by PC-88A from nickel sulfate solution, thererfore it was  necessary to conduct two stage extraction process  to extract 100% of the cobalt from the nickel sulfate solution. 

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