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Abstrak :
This book covers the rapidly growing area of friction stir welding. It also addresses the use of the technology for other types of materials processing, including super-plastic forming, casting modification, and surface treatments.

Abstrak :
Friction-vibration interactions are common but important phenomena in science and engineering. Handbook of friction-vibration Interactions introduces the principles and provides the resources to understand and work with them. A unified theoretical framework includes some of the most important engineering applications. The first three chapters in the book introduce basic concepts and analytical methods of friction and vibration. The fourth chapter presents the general principles on friction-vibration interactions, and also touches on various engineering applications. In the fifth chapter the concepts and methods are extended to some of the most critical engineering applications in high-tech industry, presenting the friction-vibration interaction principle and applications in data storage systems.

Abstrak :
Friction-stir welding (FSW) is a solid-state joining process primarily used on aluminum, and is also widely used for joining dissimilar metals such as aluminum, magnesium, copper and ferrous alloys. Recently, a friction-stir processing (FSP) technique based on FSW has been used for microstructural modifications, the homogenized and refined microstructure along with the reduced porosity resulting in improved mechanical properties. Advances in friction-stir welding and processing deals with the processes involved in different metals and polymers, including their microstructural and mechanical properties, wear and corrosion behavior, heat flow, and simulation. The book is structured into ten chapters, covering applications of the technology, tool and welding design, material and heat flow, microstructural evolution, mechanical properties, corrosion behavior and wear properties. Later chapters cover mechanical alloying and FSP as a welding and casting repair technique; optimization and simulation of artificial neural networks; and FSW and FSP of polymers.

Abstrak :
Effect of tributylphosphite on antiwear and load carrying properties of mineral base oil containing sulfurized isobutylene has been studied by using a thermodynamically approach and surface analysis data from lubricated surfaces. From this research it is concluded that increasing the concentration of tributylphosphite improves the antiwear properties of mineral base oil with and without sulfurized isobutylene. Increasing concentration of tributylphosphite improves the load carrying properties of base oil, but have no effect on load carrying properties of base oil containing high-sulfurized isobutylene. In the presence of sulfurized isobutylene, in the mild condition tributylphosphite can inhibit adsorption of sulfurized isobutylene. The good combination between these two additives was given by addition about 700 ppm P (from tributylphosphite) to the base oil containing 2000 - 6500 ppm S (from sulfurized isobutylene).

Abstrak :
Friction Stir Welding (FSW) yang ditemukan di The Welding institute (TWI), Inggris pada tahun 1991 merupakan teknik pengelasan pada kondisi padat (solid-state) sehingga memiliki keuntungan seperti tingkat deformasi yang rendah serta tidak ada material terbakar sehingga kadar asap yang dihasilkan rendah. Pada awalnya diaplikasikan pertama kali pada material aluminium. Konsep dasar pengelasan ini sangat sederhana, yaitu perkakas (tool) yang berputar yang memiliki probe dan shoulder yang dirancang khusus dimasukan diantara dua ujung plat atau benda kerja yang akan disambung, lalu secara teratur digerakan di sepanjang garis sambungan. Proses ini tergolong baru dan belum banyak diaplikasikan di indonesia. Karena itu, penelitian ini dilakukan untuk melihat pengaruh perubahan paramater pemesinan terhadap sifat mekanik material yang disambung dengan proses friction stir welding, dalam hal ini material AC4CH (JIS). Variasi parameter yang digunakan dalam penelitian ini adalah bentuk tool, sudut tool, dan kecepatan putar tool. Dimana hasil penelitian dan pengujian menunjuakan bahwa variasi parameter tersebut berpengaruh terhadap visual hasil pengelasan (kekasaran & flashing), kekuatan tarik material yang sudah di las, kekerasan pada setiap area pengelasan (weldzone) dan bentuk penampang potong dari pengelasan (Makrostruktur). ......Friction stir welding (FSW) was invented at The Welding Institute (TWI) of United Kingdom in 1991 as solid-state joining technique so it has advantages such as low level deformation, low fume because no burned material. It was initially applied to alumunium alloys. The basic concept of FSW is remarkably simple, a nonconsumable rotating tool with a specially designed Probe and shoulder is inserted into the abuttting edges of sheets or plates to be joined and subsequently traversed along the joint line. This process is relatively new and not yet widely applied in Indonesia. Therefore, the study was conducted to study the change of machining parameter can affect the mechanical properties of the material to be joined by friction stir welding process, in this case AC4CH (JIS) material. Variaton of parameters used in this research is a form of a tool, tool angle, and rotation speed of tool. Where the study and test result shown that the variation of these parameters will affect the visual welding result (roughness & flashing), tensile strength of welded material, hardness at each weldzone and cross-sectional shape of the welding material (macrostructure).

Abstrak :
Pengelasan merupakan salah satu metode penyambungan dalam bidang manufaktur untuk digunakan dalam suatu proses pembuatan produk. Pengelasan adalah penyambungan logam dengan mencairkan logam induk dan logam pengisi dengan atau tanpa tekanan dan dengan atau tanpa logam penambah menghasilkan sambungan pada logam tersebut. Micro Friction Stir Spot Welding MFSSW adalah jenis pengelasan skala mikro yang menggunakan proses gesekan pada suatu titik dalam pengelasannya. Pada penelitian ini mencari pengaruh geometri lasan dari hasil pengelasan MFSSW terhadap sifat mekanik pada Plat Aluminium AA1100. Diperoleh bahwa besaran geometri yaitu, diameter belakang back diamater, luas selimut dan kedalaman hasil pengelasan plunge depth berbanding lurus dengan beban puncak gaya geser Shear Load. Semakin luas, semakin dalam, dan semakin besar diameter belakang back diameter hasil pengelasan maka nilai beban puncak semakin besar, sementara itu untuk deviasi diameter keyhole akibat adanya vibrasi tidak menunjukan pengaruh terhadap shear load. ......Welding is one of joining method in the field of manufacturing which is used in a product manufacturing process. Welding is the bonding of metal by liquefying the parent metal and filler metal with or without pressure and with or without the adder metal resulting in a connection to the metal. Micro Friction Stir Spot Welding MFSSW is a type of micro scale welding that uses the friction process at a point in its welding. In this research looking for the influence of weld geometry from MFSSW welding result to mechanical properties on AA1100 Aluminum Plate. It is found that the magnitude of the geometry ie, back diameter, blanket width and the depth of the weld plunge depth is directly proportional to the shear load peak. The wider, deeper, and larger back diameter the higher peak load value, meanwhile for the deviation of the keyhole diameter due to vibration, does not show the effect on the shear load.

Abstrak :
Ice slurry merupakan media yang tepat dalam proses pendingan untuk menjaga kualitas hasil tangkapan ikan, karena  ice slurry dapat mendinginkan produk lebih capat dan menahan pertumbuhan bakteri tanpa merusak produk tersebut. Selama proses pengaliran ice slurry, viskositas yang rendah diperlukan agar pengaplikasian ice slurry lebih efisien. Penelitian ini bertujuan untuk menganalisa visualisasi aliran ice slurry dengan observasi rheologi pada pipa spiral yang ditambahkan dengan glycol terhadap karakterisitik aliran fluida. Konsentrasi awal food grade propylene glycol adalah 15% pada ice slurry. Kemudian fluida tersebut mengalir pada pipa spiral dengan P/D sebesar 4,3 mm, 6,7 mm dan 7,0 mm serta dibandingkan dengan pipa bulat horizontal dengan diameter 1 inch dan 1,5 inch, masing-masing pipa memiliki panjang 1,2 m. Hasilnya friction coefficient dalam pipa spiral lebih rendah daripada pipa bulat secara horizontal, sehingga viskositas yang lebih rendah terjadi di dalam pipa spiral. Sebagai tambahan, visualisasi menunjukkan bahwa aliran ice slurry akan homogen pada Froud number tinggi.

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Ice slurry is the right medium to maintain the quality of fish catches for cooling process, because ice slurry can cool the product faster and the growth of bacteria becomes slower without damaging the product. During the flow process of ice slurry, the lower viscosity is needed so that the application of ice slurry more efficient and easier to flow. This research aims to analyze the visualization of ice slurry flow with observing rheology in a spiral pipe which is added by glycol toward the characteristics of the fluid flow. The initial concentration of food grade propylene glycol was 15% on ice slurry. Then its fluid flowed on spiral pipe with 4,3 mm, 6.7 mm, and 7,0 mm of pitch per-diameter and compared to horizontal circular pipe with 1 inch and 1,5 inches of diameter, each pipe has 1.2 m of length. The result is friction coefficient in spiral pipes lower than horizontal circular pipes, so that the lower viscosity occurs on spiral pipe. In addition, visualization shows that the flow of ice slurry will be homogenous on higher Froud Number.

Abstrak :
Progress in the understanding of corrosion and corrosion resistance properties of sintered stainless steels has lead to new applications that benefit from net shape processing and more efficient material utilization.