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Abstrak :
Paduan AA 319 menqoakan paduan lgypoeutectic aluminium-sililcon, lennasuk dalam kelompok paduan aluminium seri 310K hasil proses pengecoran. Paduan ini banyak digunakan dalam induslri oromoif Dengan semakin berkembangnya tebiologi rekayasa material, diharapkan dapat diveroleh paduan aluminium yang lebih kuar unrulc dapar menggantikan material ferrous pada aplilcasi arornatyf Pemilihan aluminium paduan terutama karena berat jenisnya yang jauh lebih rendah daripada besi yang secara langsung dapat mengurangi berat kendaraan sehingga diharapkan akan menurunkan 1c0n.s‘um.s’i bahan bakar dan dapat rnengurangi tingkat polusi akibat emisi gas buang. Salah satu cara peningkaian kekuaian paduan aluminium adalah melalui microalioying yang diikuri dengan proses precipitation hardening Telah diketahui bahwa 0,01 wt. % Sn pada paduan Al-1, 7Cu (ar. %) yang mengalami proses precipitation hardening akan rnenghasillcan presipitai yang xanga! halus dan iersebar merata sehingga terjadi peningkatan paduan yang signyifkan. Alcan letapi ejék tersebut beiarn pemalz diieliti untukpaduan yang lebih kornpleks seperli AA 319. Penelitian ini rnelalrukan proses precqziration hardening pada paduan AA 319 dengan penarnbahan 0,1 wt. % Sn. Hasil dari proses precqritation hardening tersebut dilcarakterisasi dengan melakulcan pengujian kekerasan dan penganzatan srruktur mikro. Hasil peneliiian menunjukkan penambahan 0,1 wi. % Sn Ire dalarn paduan AA 319 yang diilcuti dengan precipilation hardening akan meninglcatlcan kekerasan dibanding kondisi as-cast sebesar ~60 %, dari 67 menjadi 105 BHN unnilc paduan basil cetalcan logam dan ~55 %, dari 62 menjadi 101 BHN untuk ceialcan pasir. Penambahan 0,1 wi. % Sn ke dalam paduan AA 319 diindikasikan akan menstim ulasi nukleasi partikel inrerdendritik dan presipitat di dalam matrilrs yang secara signifikan alcan rneningkaikan kekuaran paduan.

Abstrak :
Paduan AIMg9 dan AIMg5 dilebur dalam dapur krusibel lift out kapasitas 80 kg dengan variabel Fe 0,5 %, 1 % 1,5 %. Pengujian sifat mekanis kecuali pada kondisi as-cast, juga dilakukan setelah hasil solution treatment 430 ºC selama 12 jam yang diquench di dalam air. Proses penuaan buatan dilakukan pada 150 ºC dan 175 ºC selama 2 dan 4 jam. Bertambahnya kadar Fe pada AIMg5 menunjukkan tidak ada kenaikan sifat mekanis yang berarti, sedangkan untuk paduan AIMg9 dengan bertambahnya kadar Fe menunjukkan kenaikan sifat mekanis, walaupun pada beberapa kondisi kenaikan sifat mekanis tidak begitu menyolok yaitu berkisar antara 76,5 - 79 HB. Dari hasil penelitian ternyata pengaruh penambahan Mg dan Fe meningkatkan sifat mekanis paduan Al-Mg-Fe. Kemudian juga didapatkan komposisi ideal untuk paduan Al-Mg-Fe yaitu dengan AIMg9 dengan proses perlakuan panas pelarutan 430 ºC diikuti proses penuaan buatan pada temperatur aging 175 derajat C dengan waktu aging 4 jam. Setelah dilakukan proses perlakuan pelarutan pada temperatur 430 ºC dilanjuti dengan proses penuaan buatan (artificial aging) pada temperatur 150 ºC dan 175 ºC didapatkan nilai kekerasan maksimum pada kondisi Quench dan pada kondisi temperatur aging 175 ºC waktu 4 jam untuk komposisi 9 % Mg, dan 1,5 % Fe yaitu sebesar 105,5 HB dan 107 HB. Dari data ini berarti untuk komposisi 9 % Mg, dan 1,5 % Fe termasuk paduan dapat dilaku panaskan (Heat treatable).

Abstrak :
Aluminium adalah sebuah logam ringan dan ulet yang memiliki kegunaan terbanyak kedua di dunia industri setelah besi dan baja. Salah satu aluminium yang memiliki aplikasi yang luas adalah paduan Al-Mg-Si yang tergolong ke dalam aluminium seri 6xxx. Walaupun memiliki banyak keunggulan, paduan Al-Mg-Si memiliki kekurangan yaitu nilai kekerasannya yang rendah jika dibandingkan dengan aluminium seri lainnya. Oleh karena itu, peningkatan nilai kekerasan pada paduan Al-Mg-Si dapat dilakukan melalui pengerjaan dingin dan perlakuan penuaan. Kedua proses tersebut dapat digabungkan sehingga menghasilkan perlakuan yang disebut dengan perlakuan panas T8. Penelitian ini menggabungkan metode canai dingin yang dilakukan setelah perlakuan pelarutan kemudian diikuti dengan penuaan buatan pada paduan Al-1Mg-0.54Si ( % berat) yang dihasilkan melalui proses squeeze casting. Canai dingin yang dilakukan menggunakan tiga variasi deformasi yaitu 5, 10, dan 20 %. Sementara itu, penuaan dilakukan pada temperatur 180 °C selama 200 jam. Pengujian yang dilakukan adalah pengujian komposisi kimia, pengujian kekerasan, pengujian metalografi, pengujian SEM–EDS (Scanning Electron Microscope – Energy Dispersive Spectroscopy), dan pengujian XRD (X-Ray Diffraction). Hasil penelitian menunjukkan bahwa semakin besar deformasi menyebabkan butir semakin memanjang dan setelah penuaan menghasilkan peningkatan kekerasan puncak yang dicapai pada waktu yang semakin singkat. Hal ini ditunjukkan dengan paduan Al-Mg-Si setelah dideformasi sebesar 20 % yang diikuti dengan penuaan pada temperature 180 °C selama 30 menit menghasilkan nilai kekeran yang paling tinggi. Hal ini mengindikasikan adanya kombinasi dua mekanisme penguatan, yaitu pengerasan regangan dan penguatan presipitasi. ......Aluminium is a light and ductile material that has the second most use in industry after iron and steel. One of the aluminium that has a wide application is the Al-Mg-Si alloy which classified as aluminium 6xxx series. Although it has many advantages, Al-Mg-Si alloy has a disadvantage, which is its low hardness value compared to other aluminium series. Therefore, increasing the hardness value of Al-Mg-Si alloys can be done through cold working and ageing treatment. The two processes can be combined to produce a treatment known as T8 heat treatment. This research combined the cold rolling method which was carried out after solution treatment followed by ageing of the Al-1Mg-0.54Si alloy (wt. %) which was produced through squeeze casting process. Cold rolling was varied to 5, 10, and 20 % deformation. Meanwhile, ageing was carried out at 180 °C for up to 200 h. Characterization included compositional testing, hardness testing, metallographic testing, SEM - EDS (Scanning Electron Microscope - Energy Dispersive Spectroscopy) testing, and XRD (X-Ray Diffraction) testing. The results demonstrated that the higher the deformation, the longer the grain elongated, and after ageing resulted in an increase in peak hardness which was achieved in a shorter time. This was demonstrated by the Al-Mg-Si alloy after 20 % deformation and ageing at 180 °C for 30 min, which produced the maximum hardness value. This suggests the presence of two strengthening mechanisms, which included strain hardening and precipitation strengthening.

Abstrak :
Paduan Al 7XXX Al-Zn-Mg merupakan salah satu paduan aluminium yang mampu dilaku panas dan memiliki kekuatan tinggi. Paduan Al 7xxx dapat diperkuat dengan pengerasan pengendapan. Dalam proses pengerasan pengendapan, proses laku pelarutan merupakan tahapan penting dimana fasa kedua larut ke dalam matriks agar dapat bertransformasi menjadi presipitat saat proses penuaan. Selain itu, penambahan Ti dapat memperkuat paduan dengan melakukan penghalusan butir. Penelitian kombinasi laku pelarutan dengan penghalusan butir oleh Ti masih terbatas. Oleh karena itu, pada penelitian ini akan diamati pengaruh temperatur laku pelarutan terhadap struktur mikro dan sifat mekanis paduan Al-5.1Zn-2Mg dengan penambahan 0.1 berat Ti hasil squeeze casting. Paduan Al-5.1Zn-2Mg-0.1Ti hasil pengecoran dihomogenisasi pada temperatur 400 C selama 4 jam. Setelah itu, laku pelarutan dilakukan dengan variasi temperatur 220, 420, dan 490 C, dilanjutkan dengan pencelupan cepat. Selanjutnya, penuaan dilakukan pada temperatur 130 C selama 48 jam. Karakterisasi meliputi pengamatan struktur mikro menggunakan mikroskop optik, dan Scanning Electron Microscope SEM Energy Dispersive Spectroscopy EDS, pengujian kekerasan Rockwell, X-Ray Diffraction XRD, dan Simultaneous Thermal Analysis STA. Penambahan 0.1 berat Ti dapat memperbulat struktur butir paduan dan menyebabkan tegangan permukaan antarmuka matriks ?-Al menurun sehingga fasa kedua lebih mudah untuk berdifusi ke dalam matriks saat laku pelarutan. Peningkatan temperatur laku pelarutan dapat meningkatkan jumlah fasa kedua yang larut ke dalam matriks. Hal ini dapat ditunjukkan melalui fraksi volume fasa kedua dari kondisi setelah homogenisasi, yaitu 7.07 menjadi 6.74, 3.50, dan 2.75 untuk temperatur laku pelarutan 220, 420, dan 490 C. Banyaknya fasa kedua yang larut berdampak pada kekerasan yang dihasilkan setelah penuaan. Nilai kekerasan penuaan meningkat seiring dengan meningkatnya temperatur laku pelarutan, yaitu 41.68, 52.46, dan 70.98 HRB pada temperatur laku pelarutan 220, 420, dan 490 C. Selain itu, nilai kekerasan paduan dengan 0.1 berat Ti lebih tinggi dibanding paduan tanpa Ti setelah penuaan karena jumlah fasa kedua yang larut lebih besar sehingga presipitat yang terbentuk menjadi lebih banyak. ......Al 7XXX alloy is one of heat treatable aluminium alloy which has superior strength. It can be strengthened by precipitation hardening. Solution treatment in precipitation hardening sequence has an important role in which second phases will dissolve, and vacancies will be quenched in the matrix to form precipitates in the ageing process. Another strengthening can be done by the addition of Ti as grain refiner. However, there is still lack of study concerned on the combination of solution treatment with grain refining by Ti. Thus, this study is aimed to investigate the effect of solution treatment temperature on microstructure and mechanical properties of Al 5.1Zn 2Mg alloy with 0.1 wt. Ti produced by squeeze casting. As cast alloy was homogenized at 400 C for 4 h. Solution treatment was conducted at 220, 420, and 490 C, followed by rapid quenching. The alloy was subsequently aged at 130 C for 48 h. Characterization was performed by optical microscope, Scanning Electron Microscope SEM ndash Energy Dispersive Spectroscopy EDS, Rockwell hardness testing, X Ray Diffraction XRD, and Simultaneous Thermal Analysis STA. The addition of 0.1 wt. Ti resulted in rounder grains which possess lower surface tension between the Al matrix and second phase interface so that the dissolution of it will be much easier while solution treatment. Increasing solution treatment temperature leads to decreasing volume fraction of the second phases at grain boundaries. It can be known by quantitative analysis from as homogenized condition with volume fraction of 7.07 which decreased to 6.74, 3.50, and 2.75 after solution treatment at 220, 420, and 490 C, respectively. The amount of dissolved second phases will affect the final hardness after ageing process, at which the hardness was increasing with increasing solution treatment temperature. The hardness was 41.68, 52.46, and 70.98 HRB with solution treatment temperature of 220, 420, and 490 C, respectively. Besides, the hardness value of 0.1 wt. Ti added alloy was higher than that of the alloy without Ti addition. It was due to higher second phase dissolution which leads to more precipitates formed.

Abstrak :
The present work aims to improve the microstructure and hardness related properties of age hardened Al6061-SiC reinforced composites produced by a two stage stir casting method. Three composites with 2, 4, and 6wt. % (35-40μm) of SiC reinforcement are subjected to microstructural examination and hardness test at different locations to analyse the uniform distribution of the reinforcements in the matrix. As-cast composites are solution-treated at 558°C, followed by an aging treatment conducted at 100, 150, and 200°C, during which peak hardness values are noted. The peak aged samples are subjected to hardness and wear tests. In line with the objectives, ranges from 80-100% and 120-145% additional increase in hardness values are observed over as-cast alloy during the aging treatment conducted at 100, 150 and 200°C, respectively. Lower temperature aging shows substantial improvement in hardness and wear resistance over high temperature aging in each respective group. Also higher weight percentages of reinforced composites show excellent wear resistance, due to the presence of eroded iron particles from the counter surface which is regarded as a beneficial effect during the wear test. The presence of SiC particles provides more sites for the nucleation of fine precipitates. These fine precipitates hinder the movement of dislocation and thus increases hardness as well as wear resistance after the precipitation hardening treatment.

Abstrak :
The present work aims to improve the microstructure and hardness related properties of age hardened Al6061-SiC reinforced composites produced by a two stage stir casting method. Three composites with 2, 4, and 6wt. % (35-40?m) of SiC reinforcement are subjected to microstructural examination and hardness test at different locations to analyse the uniform distribution of the reinforcements in the matrix. As-cast composites are solution-treated at 558°C, followed by an aging treatment conducted at 100, 150, and 200°C, during which peak hardness values are noted. The peak aged samples are subjected to hardness and wear tests. In line with the objectives, ranges from 80-100% and 120-145% additional increase in hardness values are observed over as-cast alloy during the aging treatment conducted at 100, 150 and 200°C, respectively. Lower temperature aging shows substantial improvement in hardness and wear resistance over high temperature aging in each respective group. Also higher weight percentages of reinforced composites show excellent wear resistance, due to the presence of eroded iron particles from the counter surface which is regarded as a beneficial effect during the wear test. The presence of SiC particles provides more sites for the nucleation of fine precipitates. These fine precipitates hinder the movement of dislocation and thus increases hardness as well as wear resistance after the precipitation hardening treatment.

Abstrak :
[Stainless steel merupakan material yang paling banyak digunakan dalam pembuatan turbin pembangkit tenaga listrik Organic Rankine Cycle (ORC), karena densitasnya yang tinggi, membuat kinerja turbin menjadi kurang efisien. Salah satu alternatif penggantinya adalah paduan aluminium seri 7xx.x (Al-Zn-Mg) yang memiliki sifat mekanik terbaik dibandingkan dengan seri yang lainnya. Sifat mekanik paduan tersebut dapat ditingkatkan dengan penambahan Cr serta perlakuan pengerasan penuaan. Pada penelitian ini dipelajari pengaruh penambahan Cr sebesar 0, 0.03, 0.1 dan 0.46 wt. % pada paduan Al-10Zn-6Mg. Paduan dibuat dengan proses squeeze casting dengan tekanan sebesar 76 MPa. Pelat selanjutnya dihomogenisasi pada temperatur 400 oC selama 4 jam dan dilakukan proses pengerasan penuaan dengan melakukan solution treatment pada temperatur 440 oC selama 2 jam, pendinginan cepat, dan penuaan pada temperatur 130 oC. Karakterisasi yang dilakukan diantaranya adalah pengujian kekerasan Rockwell B, pengujian impak, pengamatan struktur mikro dengan mikroskop optik dan Scanning Electron Microscope (SEM) dilengkapi dengan Energy Dispersive X-Rays (EDX), dan Simultaneous Thermal Analysis (STA). Hasil penelitian menunjukkan bahwa penambahan Cr sebesar 0.03, 0.1 dan 0.46 wt. % meningkatkan kekerasan paduan Al-10Zn-6Mg menjadi 50.9, 52.8, 53.2 HRB yang diakibatkan oleh pengecilan ukuran SDAS, pembentukan larutan padar Cr di dalam matriks serta pembentukan fasa kedua (CrFe)Al7 dan CrAl7 pada penambahan 0.46 wt. % Cr. Penambahan Cr belum memberikan pengaruh yang signifikan terhadap proses pemanasan. ......Stainless steel is most widely used in manufacturing of turbine impeller of Organic Rankine Cycle (ORC). However, due to its high density, the performance of turbine becomes less efficient. One alternative to substitute stainless steel is 7xx.x series aluminum alloys (Al-Zn-Mg) which have good mechanical properties compared to other series. Their mechanical properties can be improved by the addition of Cr as well as precipitation hardening process. This research studied the effect of addition of Cr with variation of 0, 0.03, 0.1 and 0.46 wt. % in Al-10Zn-6Mg alloys. The samples were made by squeeze casting process with pressure of 76 MPa. The plate was then homogenized at 400 ° C for 4 hours, followed by precipitation hardening process which consisted of solution treatment at 440 ° C for 2 hours, water quenching and ageing 130 ° C. Characterization was done by Rockwell B hardness testing, impact testing, microstructure observation by using optical microscope and Scanning Electron Microscope (SEM) equipped with Energy Dispersive X-rays (EDX) and Simultaneous Thermal Analysis (STA). The results showed that addition of Cr 0.03, 0.1 and 0.46 wt. % increase the hardness of Al-10Zn-6Mg aloys to 50.9, 52.8, 53.2 HRB respectively, which were due to reduction of SDAS, solid solution strengthening of Cr in the matrix and the formation of (CrFe)Al7 and CrAl7 second phases when 0.46 wt. % Cr was added. During ageing process also increased hardness alloys, but Cr were not have a significant impact on the transformation phase. The addition of Cr not have a significant influence on the heating process. ;Stainless steel is most widely used in manufacturing of turbine impeller of Organic Rankine Cycle (ORC). However, due to its high density, the performance of turbine becomes less efficient. One alternative to substitute stainless steel is 7xx.x series aluminum alloys (Al-Zn-Mg) which have good mechanical properties compared to other series. Their mechanical properties can be improved by the addition of Cr as well as precipitation hardening process. This research studied the effect of addition of Cr with variation of 0, 0.03, 0.1 and 0.46 wt. % in Al-10Zn-6Mg alloys. The samples were made by squeeze casting process with pressure of 76 MPa. The plate was then homogenized at 400 ° C for 4 hours, followed by precipitation hardening process which consisted of solution treatment at 440 ° C for 2 hours, water quenching and ageing 130 ° C. Characterization was done by Rockwell B hardness testing, impact testing, microstructure observation by using optical microscope and Scanning Electron Microscope (SEM) equipped with Energy Dispersive X-rays (EDX) and Simultaneous Thermal Analysis (STA). The results showed that addition of Cr 0.03, 0.1 and 0.46 wt. % increase the hardness of Al-10Zn-6Mg aloys to 50.9, 52.8, 53.2 HRB respectively, which were due to reduction of SDAS, solid solution strengthening of Cr in the matrix and the formation of (CrFe)Al7 and CrAl7 second phases when 0.46 wt. % Cr was added. During ageing process also increased hardness alloys, but Cr were not have a significant impact on the transformation phase. The addition of Cr not have a significant influence on the heating process. , Stainless steel is most widely used in manufacturing of turbine impeller of Organic Rankine Cycle (ORC). However, due to its high density, the performance of turbine becomes less efficient. One alternative to substitute stainless steel is 7xx.x series aluminum alloys (Al-Zn-Mg) which have good mechanical properties compared to other series. Their mechanical properties can be improved by the addition of Cr as well as precipitation hardening process. This research studied the effect of addition of Cr with variation of 0, 0.03, 0.1 and 0.46 wt. % in Al-10Zn-6Mg alloys. The samples were made by squeeze casting process with pressure of 76 MPa. The plate was then homogenized at 400 ° C for 4 hours, followed by precipitation hardening process which consisted of solution treatment at 440 ° C for 2 hours, water quenching and ageing 130 ° C. Characterization was done by Rockwell B hardness testing, impact testing, microstructure observation by using optical microscope and Scanning Electron Microscope (SEM) equipped with Energy Dispersive X-rays (EDX) and Simultaneous Thermal Analysis (STA). The results showed that addition of Cr 0.03, 0.1 and 0.46 wt. % increase the hardness of Al-10Zn-6Mg aloys to 50.9, 52.8, 53.2 HRB respectively, which were due to reduction of SDAS, solid solution strengthening of Cr in the matrix and the formation of (CrFe)Al7 and CrAl7 second phases when 0.46 wt. % Cr was added. During ageing process also increased hardness alloys, but Cr were not have a significant impact on the transformation phase. The addition of Cr not have a significant influence on the heating process. ]

Abstrak :
Salah satu metode fabrikasi untuk membuat braket ortodontik yaitu metal injection molding. Kelebihan metode fabrikasi ini dapat menghasilkan produk dengan ukuran yang sangat kecil. Sehingga metode ini cocok digunakan sebagai metode fabrikasi braket ortodontik. Namun metode fabrikasi ini memiliki kelemahan. Terdapat proses sintering yang sulit diprediksi hasil akhirnya. Salah satu parameter yang menentukan hasil akhir sintering yaitu atmosfer. Sehingga penelitian bertujuan untuk mengetahui pengaruh temperatur pada argon sintering terhadap material SS 17-4 PH.Feedstock SS 17-4 PH dibentuk dengan menggunakan mesin injeksi menjadi bentuk kubus dengan ukuran 5 mm x 5 mm x 5 mm. Tekanan yang diberikan untuk injeksi ini yaitu 2700 psi dengan temperatur injeksi yaitu 200°C. Setelah proses injeksi, dilakukan proses penghilangan binder dengan proses debinding. Proses solvent debinding dilakukan dengan menggunakan heksana pada temperatur 50°C menggunakan magnetic stirrer selama 1,5 jam. Proses thermal debinding dilakukan menggunakan vacuum furnace pada temperatur 510°C dengan heat rate 1°C/menit dan proses holding selama 1 jam. Proses sintering dilakukan menggunakan atmosfer gas argon dengan flow rate 1 liter/menit pada temperatur 1320°C, 1340°C, 1360°C, dan 1380°C dengan heat rate 5°C/menit dan proses holding selama 1,5 jam. Hasil penelitian ini menunjukkan bahwa dengan menggunakan atmosfer argon untuk proses sintering masih terdapat adanya inklusi. Hal ini dimungkinkan terjadi karena proses thermal debinding yang kurang baik. Pada proses sintering, terbentuk fasa ?-ferrite. Fasa ini mempengaruhi proses densifikasi dari material SS 17-4 PH. Nilai densitas relatif, nilai penyusutan, dan nilai kekerasan yang dicapai pada setiap temperatur tidak mengalami perubahan yang signifikan. Hal ini menunjukkan bahwa proses sintering dengan menggunakan gas argon sudah mencapai parameter optimal pada temperatur 1320°C, 1340°C, 1360°C, dan 1380°C.

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Orthodontic brackets can be manufactured using several methods of fabrication, one of them is metal injection molding. Ability to produce very small product is the advantages of this method. However, sintering process result with this method quite unpredictable. One of the important sintering parameter is sintering atmosphere. This study is aimed to understand the influence of argon atmosphere in sintering process with different temperature.To produce orthodontic bracket with metal injection molding method, 17 4 PH stainless steel feedstock injected to the mold using injection molding machine. After injection, the binder eliminated with solvent and thermal debinding. Solvent debinding process conducted with hexane at 50 oC on magnetic stirrer for 1,5 hours. Thermal debinding were performed in vacuum furnace at 510 oC with heat rate 1 oC min and 60 min holding time. Afterward, the resulting sample were heated at 5 oC min to sintering temperatur of 1320°C, 1340°C, 1360°C, and 1380°C under 90 min holding time in argon atmosphere with flow rate 1 liter min. The results of this study indicate that, the inclusion still occur in argon atmosphere sintering process. This is possible due to poor thermal debinding process. In the sintering process, ferrite phase is formed. This phase affects the densification process of SS 17 4 PH material. The value of relative density, shrinkage, and hardness at different temperature did not change significantly. This indicates that the sintering process using argon gas has reached the optimum parameters at 1320°C, 1340°C, 1360°C, And 1380°C.

Abstrak :
ABSTRAK Kelemahan dari penggunaan braket ortodontik dalam penanganan maloklusi gigi adalah pelekatan patogen periodontal seperti Streptococcus mutans dan Lactobacillus acidophilus yang dapat menyebabkan pembentukan plak serta demineralisasi disekitar braket ortodontik. Penelitian ini bertujuan untuk mengembangkan braket ortodontik SS 17-4 PH yang memiliki sifat anti bakteri hasil dari proses metal injection molding MIM . Kemampuan braket untuk meminimalisir aktifitas penempelan bakteri ini dapat dicapai dengan pembentukan lapisan TiO2 pada permukaan braket. Lapisan TiO2 dapat dibentuk dengan metode PVD. Proses PVD magnetron sputtering dipilih karena stokiometri dari lapisan dapat dikontrol dan target dari logam berbentuk padatan dapat digunakan. Tahapan preparasi sampel dimulai dari proses injeksi menggunakan mesin metal injection molding, debinding dalam dua tahap, sintering dengan kondisi vakum dan atmosfer argon, pemolesan dan PVD magnetron sputtering. Bias negatif, energi kerja, temperatur, tekanan gas dalam ruang vakum dan aliran gas diatur sebagi parameter proses PVD. Hasil dari sintering atmosfer argon dan vakum diteliti untuk mengetahui pengaruhnya terhadap lapisan deposisi TiO2. Pada atmosfer argon, porositas yang terbentuk sebesar 7,56 . Sedangkan pada atmosfer vakum, porositas yang terbentuk sebesar 10,11 . Densitas relatif pada atmosfer argon lebih tinggi daripada vakum karena densitas mempengaruhi luas porositas yang terbentuk. Pengujian XRD dan FE-SEM dilakukan untuk mengetahui peak, unsur, serta morfologi dari senyawa yang terbentuk. Hasil akhir yang didapat dari as-deposited PVD TiO2 memiliki struktur fasa kristalin anatase dan rutile dengan rentang ukuran butir 2,27 nm dan 9,78 nm secara berurutan. Lapisan deposisi memiliki rentang ketebalan sebesar 3 m hingga 8 m.

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ABSTRACT Streptococcus mutans and Lactobacillus acidophilus as the bacterial that lived around orthodontic bracket are one of primary step for enamel demineralization which increase the tendency for plaque accumulation. This study was aimed to improve orthodontic bracket SS 17 4 PH fabricated by metal injection molding MIM with anti bacterial properties. The surface coating on the orthodontic bracket was applied by forming TiO2 layer on the substrate surface prepared by physical vapor deposition PVD that exhibit antimicrobial effect compare to substrate material one. PVD magnetron sputtering was chosen due the possibility to control thin film stoichiometry and bulk metal target can be used. PVD magnetron sputtering generally have columnar structure and smooth coating surface. Sampel preparation started from injection using metal injection molding, binder elimination with solvent and thermal debinding, sintering in vacuum and argon atmosphere, polishing and the final stage is magnetron sputtering PVD coatings. Negative bias, sputtering power and partial pressure on vacuum chamber were set as the parameters constant. The gas flowing rate of O2 in Ar O2 mixture was controlled to reveal the effects on properties of TiO2 thin coating. The results of argon and vacuum sintering atmosphere were assessed in order to know the effect in TiO2 deposition film. In argon and vacuum atmosphere, porosity area was formed in the amount of 7,56 and 10,11 . Relative density in argon atmosphere was higher than vacuum atmosphere because density influenced the content reduction of porosity. X Ray diffraction XRD and scanning electron microscopy SEM were used to obtain the information on the phase and morphology of the films. Crystalline rutile and anatase phase with 2,27 and 9,78 crystal size was measured in as deposited PVD TiO2 respectively. The deposition films was achieved in the range of 3 m 8 m.