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"The book is intended to be a handbook, a general reference, and a textbook. It contains the background educational materials on parametric analyses, extensive data, and previously unpublished master high-temperature curves for wrought and cast aluminum alloys.ASM International has previously published extensive numeric factual data on the high-temperature tensile and creep properties of aluminum alloys in the book Properties of Aluminum Alloys: Tensile, Creep, and Fatigue Data at High and Low Temperatures. In addition to interest in the properties themselves, there is a great amount of interest in how these properties are analyzed to provide estimates of long-time service performance. The latter analysis makes use of parametric time-temperature relationships based upon rate-process theory, enabling the user to combine all time-temperature exposure curves into one master curve useful for extrapolation as well as interpolation. The purpose of this book to explain and illustrate such analytical tools, and to provide a broad range of illustrative examples based upon data from the previous publication, plus much previously unpublished data from Alcoa Laboratories.The theory of and procedures for the development of master parametric relationships for high-temperature creep and stress rupture data for aluminum alloys are based upon rate-process theory. The advantages and limitations of several such analyses will be discussed. Previously unpublished master curves will be provided for a number of aluminum alloys, including wrought alloys 1100, 2024, 3003, 3004, 5050, 5052, 5154, 5454, 5456, 5083,and 6061, plus several castings alloys, including 224.0, 249.0, C355.0, and 357.0."

"Karena sifatnya yang menarik seperti ketahanan aus yang tinggi, koefisien ekspansi termal yang rendah, ketahanan korosi yang baik serta kemampuan cor yang baik, paduan aluminium - silikon hipereutektik telah menjadi suatu kandidat material untuk aplikasi - aplikasi yang membutuhkan sifat mekanis yang baik seperti piston.Walaupun demikian, paduan ini memiliki kekurangan yaitu paduan akan semakin bertambah brittle seiring dengan bertambahnya kandungan silicon dikarenakan oleh adanya silikon primer yang kasar. Terdapat berbagai cara untuk meminimalkan ukuran dari fasa silikon salah satunya adalah modifikasi dengan penambahan modifier.Pada penelitian ini, material AC8A didesain pada kondisi hipereutektik. Modifier fosfor ditambahkan dengan komposisi 0,0025 wt%, 0,0027 wt %, 0,0038 wt %, 0,0046 wt % dan 0,0061 wt % P. Untuk mengetahui sifat mekanis material, dilakukan pengujian kekuatan tarik, kekerasan serta keausan. Pengujian struktur mikro, SEM dan EDAX dilakukan untuk mengetahu perubahan struktur mikro serta fasa - fasa yang terbentuk dalam paduan.Hasil penelitian menunjukkan bahwa penambahan fosfor pada material AC8A hipereutektik akan mengubah morfologi dan ukuran silikon primer dari yang berbentuk poligonal dan kasar menjadi berbentuk blocky dan halus. Silikon eutektik juga mengalami perubahan karena pertumbuhannya yang berasal dari ujung silikon primer dan dipengaruhi oleh morfologi dan ukuran silikon prime. Silikon eutektik berubah dari jarum - jarum halus yang panjang menjadi batangan pendek dan seperti titik dengan panjang rata - rata yang lebih pendek.Hasil pengujian kekerasan menunjukkan, dengan bertambahnya kadar fosfor (0,0025 wt%, 0,0027 wt %, 0,0038 wt %, 0,0046 wt % dan 0,0061 wt %), kekerasan akan meningkat dari 38 HRB menjadi 39 HRB,40 HRB, 41 HRB dan 42 HRB. Peningkatan juga terjadi pada nilai ketahanan aus material. Sedangkan nilai kekuatan tarik tidak menunjukkan kecenderungan tertentu dikarenakan terdapatnya porositas pada sampel.

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Because of the interesting properties such as high wear resistance, low thermal expansion coefficient, high resistance to corrosion and castability, hypereutectic Al-Si alloys have become a candidate material for potential applications including piston. Nevertheless, it has a disadvantage which is it becomes more brittle as the ratio of silicon is added because of the presence of coarse primary silicon. There are a lot of ways to minimize silicon phases, one of them is modification using modifier.

In this research, aluminium alloy desaigned as AC8A was desaigned in hypereutectic condition. Phosphorus modifier was added to the melt with composition 0,0025 wt%, 0,0027 wt %, 0,0038 wt %, 0,0046 wt % dan 0,0061 wt % P. Tensile strength, hardness and wear were tested in order to know mechanical properties of material. Microstructure testing, SEM and EDAX were conducted to observe microstructure changing and phases formed in alloy.

Results of this research show that phosphorus addition in hypereutectic AC8A alloy changes the morphology and size of primary silicon from coarse polygonal to fine blocky structure. Eutectic silicon is also changed because it grows from the tip of angles on the primary silicon and is influenced by the morphology and size of primary silicon. The eutectic silicon changes from long fine needle-like shape to short bars and dots with less average length.

Hardness testing shows that by increasing phosphorus addition (0 wt %, 0,003 wt%, 0,004 wt% , 0,005 wt% dan 0,006 wt%) to the melt, hardness of the material increases from 38 HRB to 39 HRB, 40 HRB, 41 HRB, and 42 HRB. Furthermore, the value of wear resistance also increases. Nevertheless, tensile strength doesn't show any tendency because of porosity."

"Pada umumnya modifier stronsium ditambahkan pada paduan Al-Si hipoeutektik dengan kadar Si < 12 %. Penambahan modifier stronsium pada paduan Al-Si hipoeutektik terbukti efektif meningkatkan sifat-sifat mekanis paduan. Sedangkan penambahan modifier stronsium pada paduan aluminium hipereutektik belum banyak dilakukan. Penelitian ini bertujuan untuk mengetahui pengaruh penambahan modifier stronsium terhadap sifat mekanis paduan Al-Si hipereutektik (Si>12,7%). Sifat mekanis yang ingin diketahui setelah penambahan modifier stronsium adalah kekerasan, kekuatan tarik dan keausan. Dalam penelitian ini digunakan material AC8A dengan standar kadar Si sebesar 11-13%. Ditambahkan kristal silikon murni ke dalam material AC8A untuk mendapatkan kondisi hipereutektik (Si>12.7%). Perbedaan penambahan kadar stronsium dalam paduan AC8A hipereutektik merupakan variabel dalam penelitian ini, sedangkan kondisi-kondisi proses lainnya dibuat sama. Stronsium yang ditambahkan adalah sebesar 0% wt, 0.126% wt, 0.208% wt, 0.284% wt dan 0.299% wt.Hasil penelitian menunjukkan bahwa dengan penambahan modifier stronsium pada paduan AC8A hipereutektik akan mengubah bentuk silicon eutektik dari acircular menjadi fibrous dan fasa intermetalik yang terbentuk menjadi lebih tersebar. Selain itu silikon primer akan ditekan pertumbuhannya sehingga berukuran lebih kecil dan lebih tersebar merata. Hasil pengujian kekerasan dan keausan menunjukkan adanya kekerasan dan ketahanan aus yang cenderung meningkat dengan peningkatan kadar stronsium yang ditambahkan. Kekerasan cenderung meningkat secara berturut-turut dari 41 HRB menjadi 44 HRB, 45 HRB, 43 HRB dan 48 HRB. Ketahanan aus meningkat dengan laju aus yang cenderung semakin menurun secara berturut-turut dari 3.27 x 10^-5 mm3/mm menjadi 2.01 x 10^-5 mm3/mm, 1.82 x 10^-5 mm3/mm, 2.27 x 10^-5 mm3/mm, dan 1.28 x 10^-5 mm3/mm. Kekuatan tarik yang didapatkan berturut-turut dari 173 Mpa menjadi 187 Mpa, 168 Mpa, 172 Mpa dan 185 Mpa. Nilai elongasi cenderung mengalami penurunan yaitu dari 0.125 menjadi 0.123, 0.118, 0.124 dan 0.114.

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In general, stronsium modifier is added to hypoeutectic Al-Si alloys with Si content < 12%. Addition of stronsium modifier in hypoeutectic Al-Si alloys effectivelly improve mechanical properties of alloys. Whereas, addition of stronsium modifier in hypereutectic Al-Si alloys is done rarely. This research has purpose to know effect of stronsium modifier addition on mechanical properties of hypereutectic Al-Si alloys. The mechanical properties that will be observed in this research are hardness, tensile strength and wear resistant. This research use AC8A material with 11-13% standard of Si content. Silicon crystal is added to AC8A material for obtaining hypereutectic condition (Si >12.7%). The difference of amount stronsium addition is as variable on this research. The other condition casting process, such as : strontium modifier addition temperature, cast temperature, solidification time and casting time are the same. The amount of strontium modifier which added is 0,126% wt, 0.208% wt, 0.284% wt and 0.299% wt.

The result of research show that with addition of strontium modifier to hypereutectic AC8A alloy will change eutectic silicon morphology from acircular to fibrous and intermetallic phase that be formed become more uniformly dispersed. Another, the growth of primary silicon will be suppressed until finer in size and more uniformly dispersed. The results both of hardness and wear testing show presence of disposed increasing in hardness and wear resistant with rising of Sr content that be added. The hardness disposed increase, in succession, from 41 HRB to 44 HRB, 45 HRB, 43 HRB and 48 HRB. Wear resistant disposed increase with disposed decreasing of wear rate, in succession, from 3.27 x 10-5 mm3/mm to 2.01 x 10^-5 mm3/mm, 1.82 x 10^-5 mm3/mm, 2.27 x 10^-5 mm3/mm, and 1.28 x 10^-5 mm3/mm. Tensile strength that be obtained, in succession, from 173 Mpa to 187 Mpa, 168 Mpa, 172 Mpa and 185 Mpa. The value of elongation disposed decrease from 0.125 to 0.123, 0.118, 0.124 and 0.114."

"Because lithium is the least dense elemental metal, materials scientists and engineers have been working for decades to develop a commercially viable aluminum-lithium (Al-Li) alloy that would be even lighter and stiffer than other aluminum alloys. The first two generations of Al-Li alloys tended to suffer from several problems, including poor ductility and fracture toughness; unreliable properties, fatigue and fracture resistance; and unreliable corrosion resistance.Now, new third generation Al-Li alloys with significantly reduced lithium content and other improvements are promising a revival for Al-Li applications in modern aircraft and aerospace vehicles. Over the last few years, these newer Al-Li alloys have attracted increasing global interest for widespread applications in the aerospace industry largely because of soaring fuel costs and the development of a new generation of civil and military aircraft. This contributed book, featuring many of the top researchers in the field, is the first up-to-date international reference for Al-Li material research, alloy development, structural design and aerospace systems engineering."

"The purpose of this research was to find other material to be alloyed to aluminum which is cheap, not a dangerous compound, which can be carted as simple as possible and should be as far as possible found in Indonesia. Tin, zinc, and indium, are metals to be alloyed which were reported gave a better performance to aluminum sacrificial anode, although the latest mentioned is difficult to be found in Indonesia. The alloying was done by simple casting. The investigation started with alloying aluminum with 5% Zn , and tin added in varying weights from of 0.004, 0.006, 0.008, 0.01, 0.04, 0.1, to 0.2 percent. The second was also 5% Zn and Indium in varying weights as from 0.004, 0.005, 0.02, 0.05, 0.07, to 0.08 percent. Anode potential, cathodic protection potential, the capacity of anode, anode output, anode efficiency, the anode corrosion patron and induction time were points being investigated to know the anode performance, gained by immersed test in 3% sodium chloride solution. The efficiency of 77 % can be obtained from 5% Zn and 0,1 % Sn aluminum alloy and for comparison, 5% Zn and 0.05% indium aluminum alloy can reach an efficiency of 86 %. The Sn, Zn aluminum alloys, have an anode potential of -1.15 volt, cathodic protection potential -1,06 volt , capacity of 2558 A.h/kg, while the Indium, Zn aluminum alloy has -1.155 volt anode potential, capacity of 2543 Ah/kg , and anode out put of 4.76 ampere. During the immersion time Al-Zn-Sn alloys give more stable cathodic protection potential."

"Sumber energi terbarukan terus dikembangkan sebagai sumber energi alternatif. Pembangkit tenaga listrik dengan turbin radial inflow mini sistem Organic Rankine Cycle (ORC) dewasa ini banyak dikembangkan untuk memanfaatkan sumber panas bertemperatur rendah ( <150oC) seperti geotermal, energi buang pembangkit dan energi surya yang selama ini belum dimanfaatkan secara optimal. Penggunaan paduan aluminium sebagai material impeller turbin ORC telah dilakukan karena memiliki densitas yang rendah sehingga dapat mengurangi kerugian daya akibat berat impeller. Impeller turbin diproduksi dengan Proses investment casting karena memiliki bentuk geometri yang rumit, investment casting dipilih dibanding metode casting lainnya karena memiliki tingkat presisi yang baik. Penelitian ini bertujuan untuk mengembangkan paduan aluminium sebagai impeller turbin ORC yang memiliki kinerja tinggi. Dilakukan analisis gating system menggunakan software Z-Cast untuk mendapatkan sound casting. Paduan aluminium yang dikembangkan adalah paduan seri 3xx dan 7xx. Untuk memenuhi persyaratan sifat mekanik dan sifat fisik material sudu turbin, dilakukan desain dan analisis penambahan unsur paduan dan perlakuan panas. Karakterisasi material yang dilakukan adalah pengujian kekerasan, uji tarik, pemeriksaan struktur mikro dan cacat cor dengan mikroskop optik dan SEM/EDAX, pengujian komposisi kimia dengan spektrometri. Dilakukan uji fatik, uji korosi erosi pada media NaCl dan media R134a dan uji creep sesuai kondisi turbin ORC. Hasil penelitian menunjukkan desain gating system yang dipilih dapat menghasilkan sound casting. Paduan Al-9Zn-4Mg-5Cu menghasilkan kekuatan yang paling tinggi yaitu 179 MPa dengan kekerasan 91 HRB dengan adanya fasa MgZn2 dan CuAl2. Penambahan Cu menurunkan ketahanan korosi namun dapat meningkatkan ketahanan creep dengan adanya pin pada batas butir oleh fasa CuAl2. Uji Performance impeller turbin menunjukkan impeller turbin dapat bekerja dengan baik pada kondisi turbin ORC yaitu 130℃.

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Reneweble energy is developed for alternative energy resources. Power plant with radial inflow turbine system Organic Rankine Cycle (ORC) has developed using low thermal resources (<150 oC) such as geothermal, waste energy from power plant and solar energy that did not use optimally. Aluminium Alloy for turbine impeller ORC has been developed due to low density and lead to increase efficiency of turbine. Turbine impeller produced by investment casting process because of complex geometry and need high precision.

The aim of research is develop aluminium alloy for high performance turbine impeller ORC. Analysis gating system was coducted by software Z-Cast in order to achieve sound casting. Alumminium alloy series 3xx and 7xx was developed in this research. Design and analysis of element addition and also heat treatment were conducted to increase mechanical properties of material. Characterization of material was conducted by hardness test, tensile test, element analyzer, microscope optic and scanning electron microscopy (SEM/EDAX). Fatigue test, Corrosion and erosion test in slurry (3.5%NaCl+ silica sand) and R134, creep test also conducted according to impeller turbine ORC requarement.

Result of this reseach show that gating system was simulated by Z-Cast before achieved sound casting. Al-9Zn-4Mg-5Cu obtain the higher mechanical properties is 179 Mpa and 91 HRB after heat treatment due to precipitacion hardening by MgZn2 and CuAl2. Addition Cu content increase mechanical properties but decrease corrosion resistance. Addition Cu also increasecreep resistance due to fasa CuAl2 as pin/obstacle in the grain boundary. Performance test indicate that the impeller works optimally at turbine ORC condition (130 ℃)."

"Penelitian ini betujuan untuk mengetahui pengaruh temperatur cetakan dan temperatur tuang terhadap hasil pengecoran piston pada material aluminium AC8A menggunakan metode gravity die casting dengan program simulasi Z-Cast. Penelitian ini menggunakan simulasi pengecoran. Simulasi ini menggunakan software Z-Cast Pro 3.0 dan desain pada penelitian ini menggunakan software Solid Works 2021 untuk menghasilkan gambar 3D. Penelitian ini menggunakan produk piston dengan variasi variabel temperatur cetakan dan temperatur tuang. Variasi variabel temperatur cetakan yang digunakan adalah 250°C, 300°C, dan 350°C. Variabel yang digunakan untuk variasi temperatur tuang adalah 660°C, 700°C, dan 750°C. Shrinkage karena adanya proses pembekuan atau solidifikasi yang tidak merata pada produk, disebabkan oleh penyusutan volume logam cair pada proses pembekuan serta tidak mendapatkan pasokan logam cair dari riser. Pada penelitian tidak menggunakan riser dengan keadaan optimal pada temperatur cetakan 250°C dan temperatur tuang 660°C, penggunaan riser berukuran 40 mm didapatkan hasil temperature cetakan 350°C dan temperatur tuang 750°C , ukuran riser 50 mm dengan keadaan optimal pada temperatur cetakan 250°C dan temperatur tuang 660°C. Upaya untuk mengurangi cacat dengan membesarkan ukuran riser, dengan ukuran riser 50 mm akan menghasilkan produk coran denga temperatur cetakan dan temperatur tuang yang rendah. Shrinkage pada riser 50 mm lebih sedikit dibandingkan ukuran 40 mm dan tidak menggunakan riser.

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This research aims to determine the effect of mold temperature and pouring temperature on the results of piston casting on AC8A aluminum material using the gravity die casting method with Z-Cast simulation program. This research uses casting simulation. This simulation uses Z-Cast Pro 3.0 software and the design in this research uses Solid Works 2021 software to produce 3D images. This research uses piston product using variable variations in mold temperature and pouring temperature. The variable of mold temperature variations used are 250°C, 300°C, and 350°C. The variables used to vary the pouring temperature are 660°C, 700°C, and 750°C. Shrinkage is due to the uneven solidification process in the product, due to the shrinkage of the liquid metal volume during the solidification process and not getting a supply of liquid metal from the riser. In the research without using a riser with optimal conditions at a mold temperature of 250°C and a pouring temperature of 660°C, using a 40 mm riser resulted in a mold temperature of 350°C and a pouring temperature of 750°C, a riser size of 50 mm with optimal conditions at the mold temperature 250°C and pouring temperature 660°C. Efforts to reduce defects by increasing the riser size, with a riser size of 50 mm will produce cast products with low mold temperatures and casting temperatures. Shrinkage on a 50 mm riser is less than the 40 mm size and does not use a riser."