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Abstrak :
This publication reviews most of the available literature on the fatigue properties of β annealed Ti-6Al-4V and titanium alloys with similar microstructures. The focus is on β processed and β heat-treated alloys because β annealed Ti-6Al-4V has been selected for highly loaded and fatigue-critical structures, including the main wing-carry-through bulkheads and vertical tail stubs, of advanced high-performance military aircraft. An important aspect of the review is a concise survey of fatigue life assessment methods and the required types of fatigue data. This survey provides the background to recommendations for further research, especially on the fatigue behaviour of β annealed Ti-6Al-4V under realistic fatigue load histories, including the essential topic of short/small fatigue crack growth. Such research is required for independent fatigue life assessments that conform to the aircraft manufacturer?s design requirements, and also for life reassessments that most probably will have to be made during the service life of the aircraft.

Abstrak :
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.

Abstrak :
Geometri implan yang kompleks harus diproduksi dengan akurasi tinggi dan kualitas permukaan yang baik. Pemesinan freis-mikro adalah cara yang efektif dan efisien untuk mendapatkan komponen mikro tiga dimensi yang kompleks. Namun, proses pemesinan ini menimbulkan burr (duri) yang mengurangi akurasi dimensi dan kualitas permukaan. Dalam aplikasi biomedis, burr meningkatkan kemungkinan penolakan autoimun dari komponen yang dipasang. Teknik untuk menghilangkan burr (deburring) secara manual atau gerinda dapat menjadi sangat agresif, yang menyebabkan kerusakan. Teknik abrasif halus merupakan metode yang cepat dan efektif untuk menghilangkan bagian burr kecil. Proses ini menggunakan nozzle di mana material abrasif yang bercampur dengan udara bertekanan, diarahkan ke permukaan bagian yang akan dibersihkan. Teknik abrasif halus ini direkomendasikan sebagai pilihan untuk deburring komponen mikro tetapi belum diteliti untuk mikromilling beralur. Kemudian, diferensiasi sel telah terbukti dipengaruhi oleh kekasaran permukaan. Beberapa penelitian in vitro telah menunjukkan peningkatan proliferasi osteoblas pada permukaan yang agak kasar. Teknik abrasif halus akan menyebabkan peningkatan kekasaran permukaan, oleh karena itu diperlukan penelitian untuk mengetahui karakteristik perlakuan termasuk ukuran abrasif, tekanan udara, dan perubahan jarak terhadap kekasaran permukaan yang terjadi. Dengan demikian, makalah ini berfokus pada penelitian rinci tentang proses deburring implan sekrup mini yang memiliki alur (groove) dari proses pemesinan freis-mikro dengan teknik abrasif halus.

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Complex implant geometry must be produced with high accuracy and surface quality. Micromilling is an effective and efficient way to obtain complex three-dimensional micro components. However, micromilling process raises a burr which reduces dimensional accuracy and reduces surface quality. In biomedical applications, burrs increase the possibility of autoimmune rejection of installed components. Techniques for removing burrs (deburring) manually or grinding can be overly aggressive, causing damage to the feature. The fine-abrasive technique presents a fast and effective method for removing small burr parts. This process uses a nozzle through which abrasive material is mixed with compressed air, directed to the surface of the part to be cleaned. This fine-abrasive technique is recommended as an option for deburring micro components but has not been studied for grooved micromilling. Thus, this paper focuses on detailed research on deburring process of mini-screw implants that have grooves from the micromilling process.

Abstrak :
Sayap bagian atas pesawat dan tailcone merupakan komponen yang banyak menerima tension stress yang tinggi saat beroperasi. Dibutuhkan paduan material yang memiliki kekuatan tarik yang tinggi untuk mencegah terjadinya kegagalan pada komponen tersebut. Paduan titanium dipilih untuk menjadi solusi dari permasalahan tersebut karena memenuhi spesifikasi yang diinginkan serta memiliki beberapa aspek kelebihan lain yang dibutuhkan untuk industri kedirgantaraan. Namun dalam pengembangannya masih menggunakan metode konvensional dengan proses eksperimen yang memerlukan biaya yang tinggi, akurasi penelitian yang sangat ditentukan oleh data dan pengalaman empiris, serta memakan banyak waktu dan rentan terhadap kesalahan manusia. Penelitian rekayasa material menggunakan pembelajaran mesin regresi memberikan solusi yang menjanjikan untuk masalah tersebut, karena menggunakan data eksperimen maupun data dari penelitian terdahulu sehingga dapat memangkas waktu, tenaga, dan biaya dalam proses pengembangan paduan titanium. Pada penelitian ini berhasil dikembangkan model pembelajaran mesin dengan menggunakan algoritma KNN. model menghasilkan performa yang cukup baik, dibuktikan dari perbandingan nilai aktual dan prediksi serta nilai metrik model sebesar 86,22%. Selain itu, dilakukan studi berbasis fitur atomik yang menunjukkan bahwa elektron valensi berpengaruh besar terhadap sifat kekuatan tarik paduan titanium.  ......The upper wing of the aircraft and tail cone are components that receive high tension stress during operation. A material alloy with high tensile strength is required to prevent failure of these components. Titanium alloys are chosen as the solution to the problem because they meet the desired specifications and have several other advantages needed for the aerospace industry. However, its development still uses conventional methods with an experimental process that requires high costs, the accuracy of research is largely determined by empirical data and experience, and takes a lot of time and is prone to human error. Materials engineering research using regression machine learning provides a promising solution to the problem, because it uses experimental data as well as data from previous research so that it can cut time, energy, and costs in the process of developing titanium alloys. In this study, a machine learning model using the KNN algorithm was successfully developed. The model produces quite good performance, as evidenced by the comparison of actual and predicted values and the model metrik value of 86.22%. In addition, a study based on atomic features was carried out which showed that valence electrons have a major effect on the tensile strength properties of titanium alloys.

Abstrak :
Mechanical alloying (MA) was used to produce Ti-xMg alloys (x = 0, 2.5, 5, 7.5, 10 wt%Mg), and powders alloys of Ti-Mg were characterized by X-ray diffraction and Optical microscope. Investigation shows that the homogenous structure have not yet been obtained as milling Ti and Mg for 4 hours, but XRD traces indicated that mechanical alloying have produced Ti-Mg alloys as Mg peaks has disappeared from the traces. XRD results also showed that mechanical alloying and addition of Mg have direct effect on XRD broadening. Powder alloys were compacted using severe plastic deformation method, ECAP. Using Archimedes principle the density of Ti-Mg solid samples were measured and results shows that the density decreased as Mg content increases. Relative density on compacted powders indicates that ECAP has produced in excess of 98% density on each sample, and annealing improved the density. Microstructure observation using SEM shows that ECAP has produced good inter-particles boundaries as well as some porosity and undissolved Mg particles can be observed. After annealing there is improvement in boundaries in samples containing Mg, but at the same time cause segregation of Mg, which indicates diffusion of Mg occurs faster during annealing at 600_C. Mechanical properties measurement was conducted by ball indentation test method on annealed and un-annealed bulk samples, and the result were studied and analysed carefully, however, the final result of mechanical properties were not well understood and still require further and deeper investigation in the future.

Abstrak :
This book focus on the challenges faced by cutting materials with superior mechanical and chemical characteristics, such as hardened steels, titanium alloys, super alloys, ceramics and metal matrix composites. Aspects such as costs and appropriate machining strategy are mentioned. The authors present the characteristics of the materials difficult to cut and comment on appropriate cutting tools for their machining. This book also serves as a reference tool for manufacturers working in industry.

Abstrak :
ABSTRAK
Pengembangan material implan gigi berbasis titanium yaitu Ti-6Al-4V dan Ti-6Al-7Nb termodifikasi TiO2 nanotube TiNT berdopan logam Ag, telah dipelajari dalam penelitian ini. Kondisi di dalam mulut yang minim energi foton perlu adanya modifikasi material implan gigi tersebut dengan TiNT terdopankan logam Ag. Kombinasi TiNT dan pendopanan logam Ag dilakukan dengan metode Photo-Assisted Deposition PAD dapat berperan sebagai electron trapper dan menghasilkan radikal hidroksil sehingga memiliki sifat menghambat pertumbuhan biofilm. Selain itu juga meningkatkan hidrofilitas permukaan material implan gigi dan dapat meningkatkan osseointegrasi antara sel osteoblas dan implan gigi. Kemampuan titanium untuk melekat dengan sel atau jaringan hidup disekitarnya osseointegrasi dapat diamati dari pertumbuhan sel osteoblas secara in vitro. Pembuktian sifat ossointegrasi dilakukan dengan uji viabilitas sel untuk mengetahui kemampuan sel ostoblas dalam bertahan hidup menggunakan 3- 4,5-dimethylthiazol-2-yl -2,5-diphenyltetrazolium bromide MTT assay serta uji Alkaline Phosphatase ALP assay untuk mengetahui aktivitas enzim ALP yang dapat membentuk jaringan keras gigi dan tulang pada waktu inkubasi 7 dan 14 hari. Karakterisasi bahan dilakukan dengan XRD, FESEM/EDX dan Contact Angle Meter. Hasil uji in vitro yang optimum adalah Ti-6Al-4V dan Ti-6Al-7Nb dengan konsentrasi dopan logam Ag 0,10 M yang memiliki persentase viabilitas sel masing-masing sebesar 113,72 dan 99,68 dalam waktu inkubasi 14 hari. Modifikasi material implan gigi ini mampu meningkatkan pertumbuhan sel osteoblas sehingga memiliki sifat osseointegrasi yang baik.

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ABSTRACT
The development of dental implant material based titanium Ti 6Al4V and Ti 6Al 7Nb modified with TiO2 nanotube array TiNT metal doped Ag, have been studied in this research. The oral condition which has less photon of energy will inhibit activation of photocatalyst. Combination between composition of metal doped and method Photo Assisted Deposition PAD can serve as electron trapper and produces hydroxyl radicals that have the properties of inhibiting the growth of biofilm. Furthermore, this modivication can increase hidrophilicity and osseointegration cell dental implant. Osseointegration denotes the formation of interface between the bone and implant surface an can be osbserved by the growth of osteoblast cells. The surface morphology of titanium alloys was characterized using XRD, FESEM EDX and Contact Angle Meter. Moreover, the results was investigated by a test to obtain the viability of osteoblasts growth in vitro method with 3 4,5 dimethylthiazol 2 yl 2,5 diphenyltetrazoliumbromide MTT assay and Alkaline phosphatase ALP assay to reflect osteoblast activity and is thought to play a major role in bone formation and mineralization. As a coclusion, Ti 6Al 4V and Ti 6Al 7Nb doped Ag 0,10 M improves 113,72 and 99,68 of viability osteoblast cell, respectively.