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"Due to increased environmental sensitivity, renewable-based lubricants, and food grade lubricants are being considered potential alternatives to petroleum-based lubricants. Understanding of bio-lubricant in relation to abrasive wear is essential for using ball bearings in industrial implementation. This study focused on wear mechanism on ball bearings lubricated by bio-lubricants. Palm oil and coconut oils were used in this study. Coconut oils were made by two processes, namely dry and wet processing, resulting in three types of oil (virgin coconut oil [VCO], refined coconut oil [RCO], and hydrogenated coconut oil [HCO]). Full-scale bearing life tests were conducted with 300 N load with 2,840 rpm for 6 hours. Method of lubrication was circulating oil by using pump injection to the self-aligning ball bearings. The results show that the main wear mechanism, which impacted on the surfaces of inner race, outer race, and ball for different bio-lubricants, were abrasive and adhesive wear. It found that the abrasion rate was the least severe for VCO. The discrepancies of worn surfaces are thought to be as a result of the physical and chemical properties of bio-lubricants."

"Kualitas kerja bantalan sangat dipengaruhi oleh sistem pelumasannya. Pengembangan sistem pelumasan dilakukan dengan pembentukan sistem interlocking ? adsorbsi yang digabungkan dalam pelumas padat, dibentuk melalui pelapisan komposit Zn3(PO4)2 / MoS2 / MWCNT / nanografit / Na2SiO3 secara pencelupan kimiawi. Teknik one mixing layer menunjukkan kemampuan pembentukan lapisan tipis yang homogen. Kombinasi kristal phospat, phosphophyllite dan hopeite, terbentuk di matriks komposit. Permukaan kasar terbentuk pada bola komposit, tingkat kekasaran bola komposit I: 1,350 m, komposit II: 1,000 m dan komposit III: 0,475 m. Ketebalan komposit berada pada daerah 5 ? 6 m. Pelumas dapat teradsorb dalam lapisan komposit, terjadi interaksi ikatan hidrogen antara pelumas dan kristal phosphat. Multi walled carbon nanotube mempunyai kemampuan interlocking dan pelumas padat yang lebih baik dibandingkan grafit ketjenblack. Bola komposit memiliki ketahanan friksi yang lebih baik dibanding bola tanpa pelapisan ataupun bola berlapis MoS2; bola komposit II memiliki rasio umur pakai tertinggi (17,92) untuk uji friksi satu kali pelumasan, sedangkan umur pakai tertinggi uji friksi simulasi pelumasan berkala dimiliki oleh kedua bola komposit II dan III (rasio > 28,3).

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Work quality of bearing is strongly influenced by its lubrication system. Development of lubrication system can be done by create an interlocking and adsorbtion system which is combined by solid lubricants. It was formed through a coating of Zn3(PO4)2 / MoS2 / MWCNT / nanografit / Na2SiO3 composite by chemical immersing. One mixing layer technique show good ability to produce homogeneous thin layer. Combinations of phosphate crystals, phosphophyllite and hopeite, was formed in the composite matrix. Rough surface was formed on composite ball, roughness of composite I ball: 1.350 m, composites II ball: 1.000 m and composites III ball: 0.475 m. Thickness of composite is in the region of 5 - 6 m. Lubricants can be adsorbed in composite layer, lubricants and phosphate crystals have hydrogen bonding interaction. Multi walled carbon nanotube has better interlocking and solid lubricants capabilities than its graphite ketjenblack. Composite ball has a better friction resistance than no coating ball and MoS2 coated balls; composite II ball has the highest lifetime ratio (17.92) for a one-time lubrication friction test, while the highest lifetime friction test simulating periodic lubrication is owned by both of composites II and III ball (ratio> 28.3)."

"The increasing prices of commercial lubricants and global attention towards a green environment have become the key issues to re-think about alternatives to commercially available lubricants. With these prospects in mind, vegetable oils can be utilized as an option to commercially available lubricants, due to their biodegradable and nontoxic nature. Moreover, they possess certain advantages like lower volatility and high flash/ fire points, higher viscosity index, excellent lubricity and cost savings. These properties of bio-lubricants are more often considered as important in the preparation of various bio-fuels. So far bio-lubricants have been employed in the preparation and testing of bio-fuels for various automotive applications. The primary aim of this study is to infer a novel application of bio-lubricants in the subject area of machining. During machining, machinability and performance are most frequently determined by the friction and wear characteristics of the tool and workpiece materials. In this work, first friction and wear characteristics of bio-lubricants (blended vegetable oils in various proportions) formulated from Palm and Mahua oils have been investigated using a Pin-on-Disk wear testing machine. A bio-lubricant (composed of blended vegetable oils) is synthesized by using two base oils and blending them in different possible proportions. The tribological properties have been studied over an AISI 1040 Steel disc specimen with aluminium pins under various bio-lubricant environments using the Taguchi Design of Experiment (DOE). During the study, it was observed that the abrasive and adhesive wear were the main wear mechanisms that occurred in the tests. The results have shown that total wear of the test specimens under all machining conditions for 90% Mahua and 10% Palm blended oil combination is found to be at a minimum."

"Kalsium karbonat merupakan aditif padat yang dapat meningkatkan performa anti-wear pada pelumas gemuk. Kinerja aditif dalam mengurangi jumlah keausan dipengaruhi oleh ukuran partikelnya, dimana ukuran partikel yang semakin kecil akan memberikan sifat ketahanan aus yang semakin baik. Namun, partikel yang semakin kecil akan memiliki harga yang semakin mahal. Penelitian ini bertujuan untuk meningkatkan performa gemuk dalam mengurangi jumlah keausan dan memaksimalkan efisiensi biaya dengan mengkombinasikan ukuran partikel aditif kalsium karbonat, yaitu ukuran mikro diatas asperities (Mb), ukuran mikro dibawah asperities (Mk) dan ukuran nano (N). Tiga ukuran tersebut dikombinasikan dengan komposisi berbeda. Pembuatan gemuk dilakukan melalui reaksi saponifikasi minyak sawit sebagai bahan dasar dengan asam 12-hidroksistearat, kalsium hidroksida, dan asam asetat sebagai pengental dan pengompleks. Gemuk bio kalsium kompleks dengan tingkat kekerasan gemuk multiguna (NLGI 2) yang dihasilkan selanjutnya dicampur dengan bubuk aditif kalsium karbonat sebanyak 1% dari basis gemuk, Partikel dikarakterisasi ukurannya menggunakan SEM. Gemuk yang dihasilkan dilakukan pengujian untuk mengetahui jumlah keausan menggunakan uji four ball dan untuk mengetahui pengaruh terhadap karakteristik gemuk yaitu konsistensi, kemuluran, dan dropping point. Hasil penelitian menunjukkan bahwa pada kombinasi mikropartikel dibawah ukuran asperities dan nanopartikel dengan rasio 50% : 50% menghasilkan performa terbaik dalam mengurangi keausan dan mengurangi biaya bahan baku pembuatan gemuk. Penambahan aditif tidak terlalu memengaruhi tingkat penetrasi, kemuluran dan dropping point.

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Calcium carbonate is a solid additive that is well-known for improving the anti-wear performance of bio greases. The performance of additives in reducing the amount of wear can be affected by its particle size, where the smaller particle size will provide better anti-wear performance. However, smaller particles are more expensive. Therefore, research is needed on the particle size combination of calcium carbonate particles on tribological performance to reduce the amount of wear and achieve cost efficient grease. The grease is made through the saponification reaction of palm oil as base oil with 12-hydroxystearic acid, calcium hydroxide, and acetic acid as thickeners and complexing agents. The resulting NLGI 2 calcium complex bio-grease (multi-purpose grease) was then mixed with 1% w/w calcium carbonate powder. The additive particle size was varied into three sizes: micro size above asperities (Mb), micro size below asperities (Mk), and nano size (N). The sizes were varied by its compositions. Particles were characterized using SEM, meanwhile bio-grease using penetration, drop point, and four ball tests. The results showed that the combination of microparticles below asperities (Mk) and nanoparticles (N) with a ratio of 50% : 50% produced the best performance in reducing wear and reducing the cost of raw material for making grease. The addition of additives does not significantly affect the level of penetration, fibril texture and dropping point."

"[ABSTRAKTesis ini membahas pengaruh penambahan aditif pemodifikasi gesekan serbuk MoS2 ukuran 1 5 m dengan jumlah mulai 0 05 0 1 0 5 1 dan 2 berat dan ukuran 90 nm sebesar 0 05 0 1 0 5 pada minyak lumas dasar mineral HVI 60 terhadap karakteristik gesekan dan perlindungan keausannya Aditif ukuran 90 nm dan minyak lumas dasar dicampur dan diaduk menggunakan magnetik stirrer selama enam puluh menit pada suhu 50oC setelah itu dimasukkan ke dalam ultrasonic homogenizer selama satu jam sedangkan aditif ukuran 1 5 m pada suhu 75oC tanpa menggunakan ultrasonic homogenizer Campuran yang dihasilkan diuji karakteristik gesekan dan perlindungan keausannya menggunakan mesin uji four ball dan mesin uji SRV Analisis dilakukan pada material bola uji menggunakan optical emission spectroscopy OES goresan permukaan bola uji menggunakan scanning electron microscope SEM dan minyak lumas sisa pengujian dengan alat uji rotating disk electrode RDE Hasil penelitian menunjukkan bahwa penambahan aditif meningkatkan perlindungan keausan dengan dosis optimal sebesar 0 1 berat dengan rincian ukuran 1 5 m perbaikannya sebesar 23 dan ukuran 90 nm sebesar 11 Pengamatan permukaan goresan menunjukkan mekanisme keausan terjadi secara adesif dan abrasif Data yang diperoleh dari penelitian ini bisa digunakan sebagai dasar dalam pembuatan minyak lumas untuk aplikasi tertentu dengan mutu yang lebih baik

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ABSTRACTThis thesis discusses the influence of MoS2 friction modifier FM addition in the form of powder with two different mesh sizes i e 90 nm and 1 5 um on the friction and wear characteristic of HVI 60 base oil The variation of MoS2 were 0 05 0 1 0 5 weight whereas MoS2 1 5 um were 0 05 0 1 0 5 1 and 2 weight MoS2 additive 90 nm was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 50oC and homogenized in ultrasonic homogenizer for 1 hour For the MoS2 1 5 um the additive was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 75oC without using ultrasonic homogenizer Friction and wear characteristic of these mixtures were tested using four ball and SRV test rig Ball specimen surfaces were analyzed by using optical emission spectroscopy OES the wear scars were analyzed by using scanning electron microscope SEM while used mixtures from the test were analyzed by using rotating disk electrode RDE The results of the tests showed that the addition of 0 1 weight MoS2 additive both in 90 nm and 1 5 um resulted in an optimum increase in friction and wear characteristic of 23 and 11 respectively Observation on the wear scar showed that adhesive and abrasive wear mechanism were involved in the wear process The results of this research could be applied in production of lubricating oils for certain applications to improve their quality ;This thesis discusses the influence of MoS2 friction modifier FM addition in the form of powder with two different mesh sizes i e 90 nm and 1 5 um on the friction and wear characteristic of HVI 60 base oil The variation of MoS2 were 0 05 0 1 0 5 weight whereas MoS2 1 5 um were 0 05 0 1 0 5 1 and 2 weight MoS2 additive 90 nm was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 50oC and homogenized in ultrasonic homogenizer for 1 hour For the MoS2 1 5 um the additive was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 75oC without using ultrasonic homogenizer Friction and wear characteristic of these mixtures were tested using four ball and SRV test rig Ball specimen surfaces were analyzed by using optical emission spectroscopy OES the wear scars were analyzed by using scanning electron microscope SEM while used mixtures from the test were analyzed by using rotating disk electrode RDE The results of the tests showed that the addition of 0 1 weight MoS2 additive both in 90 nm and 1 5 um resulted in an optimum increase in friction and wear characteristic of 23 and 11 respectively Observation on the wear scar showed that adhesive and abrasive wear mechanism were involved in the wear process The results of this research could be applied in production of lubricating oils for certain applications to improve their quality ;This thesis discusses the influence of MoS2 friction modifier FM addition in the form of powder with two different mesh sizes i e 90 nm and 1 5 um on the friction and wear characteristic of HVI 60 base oil The variation of MoS2 were 0 05 0 1 0 5 weight whereas MoS2 1 5 um were 0 05 0 1 0 5 1 and 2 weight MoS2 additive 90 nm was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 50oC and homogenized in ultrasonic homogenizer for 1 hour For the MoS2 1 5 um the additive was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 75oC without using ultrasonic homogenizer Friction and wear characteristic of these mixtures were tested using four ball and SRV test rig Ball specimen surfaces were analyzed by using optical emission spectroscopy OES the wear scars were analyzed by using scanning electron microscope SEM while used mixtures from the test were analyzed by using rotating disk electrode RDE The results of the tests showed that the addition of 0 1 weight MoS2 additive both in 90 nm and 1 5 um resulted in an optimum increase in friction and wear characteristic of 23 and 11 respectively Observation on the wear scar showed that adhesive and abrasive wear mechanism were involved in the wear process The results of this research could be applied in production of lubricating oils for certain applications to improve their quality ;This thesis discusses the influence of MoS2 friction modifier FM addition in the form of powder with two different mesh sizes i e 90 nm and 1 5 um on the friction and wear characteristic of HVI 60 base oil The variation of MoS2 were 0 05 0 1 0 5 weight whereas MoS2 1 5 um were 0 05 0 1 0 5 1 and 2 weight MoS2 additive 90 nm was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 50oC and homogenized in ultrasonic homogenizer for 1 hour For the MoS2 1 5 um the additive was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 75oC without using ultrasonic homogenizer Friction and wear characteristic of these mixtures were tested using four ball and SRV test rig Ball specimen surfaces were analyzed by using optical emission spectroscopy OES the wear scars were analyzed by using scanning electron microscope SEM while used mixtures from the test were analyzed by using rotating disk electrode RDE The results of the tests showed that the addition of 0 1 weight MoS2 additive both in 90 nm and 1 5 um resulted in an optimum increase in friction and wear characteristic of 23 and 11 respectively Observation on the wear scar showed that adhesive and abrasive wear mechanism were involved in the wear process The results of this research could be applied in production of lubricating oils for certain applications to improve their quality ;This thesis discusses the influence of MoS2 friction modifier FM addition in the form of powder with two different mesh sizes i e 90 nm and 1 5 um on the friction and wear characteristic of HVI 60 base oil The variation of MoS2 were 0 05 0 1 0 5 weight whereas MoS2 1 5 um were 0 05 0 1 0 5 1 and 2 weight MoS2 additive 90 nm was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 50oC and homogenized in ultrasonic homogenizer for 1 hour For the MoS2 1 5 um the additive was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 75oC without using ultrasonic homogenizer Friction and wear characteristic of these mixtures were tested using four ball and SRV test rig Ball specimen surfaces were analyzed by using optical emission spectroscopy OES the wear scars were analyzed by using scanning electron microscope SEM while used mixtures from the test were analyzed by using rotating disk electrode RDE The results of the tests showed that the addition of 0 1 weight MoS2 additive both in 90 nm and 1 5 um resulted in an optimum increase in friction and wear characteristic of 23 and 11 respectively Observation on the wear scar showed that adhesive and abrasive wear mechanism were involved in the wear process The results of this research could be applied in production of lubricating oils for certain applications to improve their quality , This thesis discusses the influence of MoS2 friction modifier FM addition in the form of powder with two different mesh sizes i e 90 nm and 1 5 um on the friction and wear characteristic of HVI 60 base oil The variation of MoS2 were 0 05 0 1 0 5 weight whereas MoS2 1 5 um were 0 05 0 1 0 5 1 and 2 weight MoS2 additive 90 nm was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 50oC and homogenized in ultrasonic homogenizer for 1 hour For the MoS2 1 5 um the additive was mixed with base oil and stirred with magnetic stirrer for 60 minutes at 75oC without using ultrasonic homogenizer Friction and wear characteristic of these mixtures were tested using four ball and SRV test rig Ball specimen surfaces were analyzed by using optical emission spectroscopy OES the wear scars were analyzed by using scanning electron microscope SEM while used mixtures from the test were analyzed by using rotating disk electrode RDE The results of the tests showed that the addition of 0 1 weight MoS2 additive both in 90 nm and 1 5 um resulted in an optimum increase in friction and wear characteristic of 23 and 11 respectively Observation on the wear scar showed that adhesive and abrasive wear mechanism were involved in the wear process The results of this research could be applied in production of lubricating oils for certain applications to improve their quality ]"

"Aditif pelumas merupakan komponen utama dari pelumas. Aditif memiliki sifat anti-aus dan tahan pada tekanan tinggi. Pembuatan aditif dilakukan dengan proses sulfurisasi minyak biji kapuk randu dengan gas H2S. Proses sulfurisasi dimodifikasi dengan tambahan metode sirkulasi H2S yang berfungsi untuk meningkatkan efisiensi penggunaan H2S. Radiasi sinar UV dengan panjang gelombang 254 nm juga digunakan untuk mempercepat proses sulfurisasi. Proses sulfurisasi dinyatakan berhasil karena ada ikatan C-S pada hasil spektrum FTIR di puncak 581,25 cm-1. Hal ini diperkuat dengan hasıl kandungan sulfur tertinggi yang didapatkan pada sampel minyak biji kapuk randu tersulfurisasi 20 jam sebesar 32.682 ppm dengan viskositas 72,17 cSt dan densities 0,92 g/cm2. Pengujian performa aditif dilakukan dengan uji four-ball untuk melihat performa ketahanan anti-aus pada aditif. Pengujian performa dilakukan dengan mencampurkan minyak mineral sebagai minyak dasar dan aditif. Hasil uji keausan terbaik terdapat pada formulasi minyak mineral dan 10% aditif tersulfurisasi selama 20 jam yang meningkatkan performa keausan hingga 98% dan memiliki rasio sulfur sebesar 3.268 ppm. Rasio sulfur ini sudah sebanding dengan rasio aditif ZDDP yang umum digunakan sebesar 3.393 ppm. Selanjutnya dilakukan pengujian korosifitas pada formulasi minyak mineral dan aditif tersulfurisasi selama 20 jam dan dihasilkan bahwa formulasi tersebut sangat rendah terhadap korosi dan aman digunakan pada mesin kendaraan

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Lubricant additives are the main components of lubricants. These additives possess anti-wear properties and can withstand high pressure. The production of additives is carried out through the sulfurization process of kapok seed oil using H2S gas. The sulfurization process is modified with an additional H2S circulation method to enhance the efficiency of H2S usage. UV radiation with a wavelength of 254 nm is also used to accelerate the sulfurization process. The sulfurization process is deemed successful due to the presence of C-S bonds in the FTIR spectrum at the peak of 581.25 cm-1. This is further supported by the highest sulphur content found in the kapok seed oil sample sulfurized for 20 hours, which was 32,682 ppm with a viscosity of 72.17 cSt and a density of 0.92 g/cm2. Performance testing of the additive was also conducted using a four-ball test to evaluate the anti-wear performance of the additive. The performance test was carried out by mixing mineral oil as the base oil and the additive. The best wear test results were obtained from the formulation of mineral oil and 10% additive sulfurized for 20 hours, which improved wear performance by up to 98% and had a sulphur ratio of 3,268 ppm. This sulphur ratio is comparable to the commonly used ZDDP additive ratio of 3,393 ppm. Additionally, a corrosiveness test was conducted on the formulation of mineral oil and the additive sulfurized for 20 hours, and it was found that this formulation is very low in corrosion and safe for use in vehicle engines."