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"Buku "Express and standard : ductile iron pipelines" ini membahas tentang spesifikasi pipa besi."

"Dalam pengoperasiannya, kendaraan pengangkat personel alutsista umumnya menggunakan material baja sebagai penyusun utamanya. Penggantian material baja dengan komposit aluminium diharapkan mampu membuat kendaraan tersebut menjadi ringan dan tetap mempunyai ketangguhan yang baik. Pada penelitian sebelumnya, komposit aluminium Al-9Zn-6Mg-3Si dengan berpenguat ZrO2 sudah mampu menahan peluru tipe III, namun mengalami keretakan pada pelat bagian belakang. Oleh karena itu, pada penelitian ini, untuk meningkatkan ketangguhan pelat komposit, ditambahkan unsur Cr pada matriks. Penambahan kadar Cr dipilih karena mampu meningkatkan kekuatan komposit tanpa harus mengorbankan sifat ketangguhan dari komposit bermatriks Aluminium. Komposit yang dipelajari memiliki matriks Al-10Zn-6Mg-2Si dengan penambahan unsur Cr sebanyak 0, 0.06, 0.15, 1.69 wt.% dengan berpenguat partikel ZrO2 sebanyak 5 vol.%.. Proses pembuatan komposit dilakukan dengan menggunakan metode squeeze casting pada tekanan sebesar 76 Mpa. Pelat komposit kemudian dilakukan laku pelarutan pada suhu 4500C selama 1 jam dan laku penuaan pada 2000C selama 1 jam. Pengujian yang dilakukan meliputi: Optical Emmision Spectrometry (OES), uji kekerasan, uji impak, pengamatan mikrostruktur menggunakan Mikroskop Optik dan Scanning Electron Microscopy (SEM) yang dilengkapi dengan Energy Dispersive X-Ray Spectroscopy (EDX), serta X-Ray mapping. Hasil pengujian menunjukan adanya peningkatan kekerasan pada pelat komposit dan penurunan ketangguhan seiring dengan kenaikan kadar Cr di dalam pelat komposit. Kandungan ZrO2 pada pelat komposit sulit dideteksi dan tersebar secara tidak merata. Hasil pengamatan SEM dan EDX mendeteksi adanya fasa baru intermetalik (CrFe)Al7 yang menggetaskan material. Adanya unsur Fe yang tinggi serta fasa intermetalik Cr yang muncul pada penambahan kadar Cr sebanyak 1.69% menjadi penyebab penurunan nilai impak dari pelat komposit Al-10Zn-6Mg-2Si tersebut.

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In operation, the personal carrying vehicle uses steel material as a major constituent. Replacement of steel with lighter material, such as aluminum composite is expected to make the vehicles become even lighter without sacrifying their toughness. Previous research had shown that Al-9Zn-6Mg-3Si aluminum composite with ZrO2 reinforcement was able to stop type III bullet, but cracks still occur at the back surface of the composite. Therefore in this research, Cr was added to increase the toughness of the matrix.

The studied composite composed of Al-10Zn-6Mg-2Si matrix with addition of Cr with the amount of 0, 0.06, 0.15, and 1.69% with5 vo.% ZrO2 particles. The composite was manufactured through squeeze casting processat the pressure of 76 Mpa. Solution Treatment was applied at the temperature of 4500C for 1 hour, followed by aging at 2000C for 1 hour. The analysis is done by : Optical Emmision Spectrometry (OES), hardness test, impact test, microsructure observation by Optical Microscopy, Scanning Electron Microscopy (SEM) linked with Energy Dispersive X-Ray (EDX), and X-Ray mapping.

The results showed that the increase in Cr content resulted in the increase of hardness of the composite. The ZrO2 particles were difficult to detect and found to be unevenly spreaded. The observation of SEM and EDX detected the presence of a new intermetallic phase (CrFe)Al7 that makes the composite brittle. The high level of Fe content and (CrFe)Al7 intermetallic phase in the 1.69wt.% Cr Cr containing found to decrease the impact value of the composite."

"Dalam penelitian ini dilakukan pengambilan kembali lithium dan cobalt dari limbah baterai Li-Ion. Proses yang digunakan yaitu terdiri dari proses leaching dan dilanjutnya dengan proses ekstraksi cair-cair. Proses leaching dilakukan dengan menggunakan asam sitrat sebagai leaching agent. Kemudian dilakukan proses ekstraksi cair-cair dengan menggunakan Cyanex® 272 sebagai ekstraktan. Hasil percobaan diuji menggunakan metode pengujian atomic absorption spectroscopy (AAS). Proses leaching dengan menggunakan asam sitrat 1,5 M dapat menghasilkan logam lithium hingga mendekati 100% dan cobalt mendekati 90%. Proses ekstraksi cair-cair dengan pH fasa akuatik 6,6 dan konsentrasi Cyanex® 272 sebesar 0,2 M, menghasilkan 57,4% logam lithium dari total lithium awal dan 66,2% cobalt dari total cobalt awal.

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In this study conducted recovery of lithium and cobalt from waste of lithium ion batteries. The process that will be used is consisted of leaching and followed by solvent extraction. Leaching has done by using citric acid. Then, solvent extraction was done with Cyanex® 272 as the extractant. The lithium and cobalt concentration in the aqueous phase is characterized by atomic absorption spectroscopy (AAS). Leaching process with 1.5 M citric acid can recover lithium nearly 100% and cobalt nearly 90%. Solvent extraction was done with pH of aqueous phase 6.6 and Cyanex® 272 0.2 M produce more than 55% lithium from the total initial of lithium and more than 65% of cobalt from the total initial is recovered."

"This book explains the metallurgy of steel and its heat treatment for non-metallurgists. It starts from simple concepts—beginning at the level of high-school chemistry classes—and building to more complex concepts involved in heat treatment of most all types of steel as well as cast iron. It was inspired by the author when working with practicing bladesmiths for more than 15 years. Most chapters in the book contain a summary at the end. These summaries provide a short review of the contents of each chapter. This book is THE practical primer on steel metallurgy for those who heat, forge, or machine steel."

"Offering a comprehensive source of information on metallographic techniques and their application to the study of metals, ceramics, and polymers, this work is available once again from ASM. It contains an extensive collection of micro- and macrographs. This proven reference for metallographers, engineers, technicians has also been found useful by students studying physical metallurgy, metallography and materials science."

"A complete introduction to titanium and its alloys, with coverage of all technical aspects of titanium with sufficient metals property data for most users. For users at any level of experience with titanium, providing both technical information and an executive summary of the metal and its uses. DLC: Titanium."