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"ABSTRAKDidalam proses pembuatan semen sering dijumpai adanya kebocoran p ada pipa-pipa yang menuju kepenampungan pembakaran. Bahan baku semen yang terbuang ini jumlahnya cukup besar sehingga dapat mengganggu lingkungan bila tidak dimanfaatkan. Gagasan memanfaatkan buangan bahan baku semen ini sebagai filler pada campuran Split Mastik Aspal karena secara fislk bentuk butirannya mempunyai ukuran yang sama.Dalam penelitian ini membandingkan kinerja bahan baku semen dengan portland-cement dengan variasi kadar filler yang sama yaitu 6%, 7%, 8% dan 10%, sedangkan kadar aspalnya adalah 6%, 6.5 %, 7% dan 8%. Dari variasi-variasi ini didapat kadar aspal optimum berdasarkan spesifikasi campurran Split Mastik Aspal melalui metode pengujian Marshall.Dari hasil pengujian menunjuklam bahwa kinerja bahan baku semen sebagai filler masih lebih rendah dari kemampuan portland-cement sebagai filler. Tetapi kinerja bahan baku semen sebagai filler campurran Split Mastik Aspal masih mememihi persyaratan campuran Bina Marga. Sehingga bahan buangan ini dapat dimanfaatlam sebagai filler menggantikan portland-cement yang relatif lebih mahal."

"Technology of recycling can be implemented in the road maintenance program such as road rehablilitation or betterment project...."

"Dimethyl ether (DME) is a type of renewable energy that could replace the use of fossil fuel in Indonesia. Nevertheless, DME can cause degradation of rubber-based materials. Therefore, the performance of rubber that has been degraded by DME must be improved. This research study aims are to determine the degradation characteristics of modified vulcanized natural rubber in a DME environment. The effect of the filler (carbon black) and plasticizer (minarex-B) components of vulcanized natural rubber was examined. The vulcanized rubber samples were comprised of 10, 30, and 60 parts per hundred rubbers (phr) of filler and 0, 10 and 20 phr of plasticizer. The degradation of the mass and mechanical properties of the rubber were investigated. Degradation testing was conducted by immersing the samples inside a pressure vessel that was filled with the liquid phase of DME. The results indicate that the increasing of the filler composition reduces the impact of degradation, while the increasing of the plasticizer composition has the opposite effect. The plasticizer is needed to distribute the filler to all parts of the rubber. Consequently, a filler composition of 30 phr and a plasticizer composition of 10 phr provide a vulcanized natural rubber with optional protection against the degradation caused by DME. The characteristics of natural rubber, as measured by Fourier Transform Infra-Red Spectroscopy (FTIR) proved that DME does not damage the structure of the polymer chains, although DME may react with some ingredients in the rubber that have a similar polarity."

"This research was done to investigate influence of the base metal surface roughness on the BAg-8 spreading behavior and to get a proper surface roughness number for large area brazing. The filler metal was melted at 830o C for 15 minutes on a S50C surface for with various roughness levels. After solidified, the spreading area was observed and characterized in macro and micro scale. The results show that physically the filler spreading consists of two kinds of spreading forms: true and apparent filler spreading with composition of the both being almost same; 77% Ag and 23% Cu. For some roughness numbers, irregularities in uniformity of the heating and cooling process on the filler and dissolving of contaminant into the molten filler caused the true spreading that tend to separate became several parts and tend to flow out from initial placement. Increasing of the surface roughness tends to increase the capillarity effect and to decrease imbalance in the surface tension. Optimum surface roughness was obtained at Rz = 0.92. At this number, the ratio, as well as fitness of the true spreading with initial condition, was at the maximum. During the application process, this condition is predicted as being able to prevent or avoid weaknesses in the joint, thereby increasing the joint strength and its appearance quality."

"Dimethyl ether (DME) is a type of renewable energy that could replace the use of fossil fuel in Indonesia. Nevertheless, DME can cause degradation of rubber-based materials. Therefore, the performance of rubber that has been degraded by DME must be improved. This research study aims are to determine the degradation characteristics of modified vulcanized natural rubber in a DME environment. The effect of the filler (carbon black) and plasticizer (minarex-B) components of vulcanized natural rubber was examined. The vulcanized rubber samples were comprised of 10, 30, and 60 parts per hundred rubbers (phr) of filler and 0, 10 and 20 phr of plasticizer. The degradation of the mass and mechanical properties of the rubber were investigated. Degradation testing was conducted by immersing the samples inside a pressure vessel that was filled with the liquid phase of DME. The results indicate that the increasing of the filler composition reduces the impact of degradation, while the increasing of the plasticizer composition has the opposite effect. The plasticizer is needed to distribute the filler to all parts of the rubber. Consequently, a filler composition of 30 phr and a plasticizer composition of 10 phr provide a vulcanized natural rubber with optional protection against the degradation caused by DME. The characteristics of natural rubber, as measured by Fourier Transform Infra-Red Spectroscopy (FTIR) proved that DME does not damage the structure of the polymer chains, although DME may react with some ingredients in the rubber that have a similar polarity."

"Alumium merupakan material yang dominan digunakan dalam dunia industri, industri manufaktur banyak menghasilkan produk aluminium dengan metode casting. Salah satu yang perlu diperhatikan dalam proses pengecoran adalah coating. Coating pada proses pengecoran bertujuan mengurangi kejutan termal. Zirkon merupakan material yang biasa dipakai sebagai material pengisi, tetapi zirkon memilik harga yang relative mahal, sehingga pada penelitian ini akan dibahas pengaruh dari material pengisi alumina dan talc terhadap zirkon untuk menghasilkan refractory coating yang baik. Penelitian ini berfokus pada variasi konsentrasi dan juga temperatur pengeringan yang ideal sehingga didapatkan coating yang baik. Analisa pada penelitian ini antara lain Pengujian X-Ray Diffraction (XRD), X-Ray Flourensi (XRF), Particle Size Analyzer (PSA), viscosity, thermal analysis mengguanakan differential thermal analysis (DTA), pengambilan gambar dilakukan dengan Scanning Electron Microscope (SEM) yang dilengkapi oleh fasilitas EDX untuk mengetahui kandungan material yang ada pada material coating. Pengujian pull off strength dilakukan untuk mengetahui sifat adhesive dari material coating. Konduktivitas termal dilakukan untuk mengetahui nilai konduktivitas termal dari lapisan coating. Hasil dari pengujian bahwa material alumina dan talc dapat digunakan sebagai filler material bahan baku refractory coating. Ukuran partikel kecil dapat mempercepat proses homogenisasinya, sementara distribusi partikel berpengaruh terhadap konsentrasi tegangan. Bahan baku ball mill lebih baik distibusi partikelnya.

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Alumium is the dominant material used in the industrial company, many manufacturing industries produce aluminum products by the casting method. Coating is one that needs to be considered in the casting process. Coating in the casting process helps reduce thermal shock. Zircon is a material commonly used as a filler, but the zircon has a relatively expensive price, so this research will discuss alumina fillers and talc to zircon to produce a good fire resistant coating. This research focused on variation and ideal temperature so that a good coating was obtained. The analysis in this study include X-Ray Diffraction Testing (XRD), X-Ray Flourence (XRF), Particle Size Analyzer (PSA), viscosity, thermal analysis using differential thermal analysis (DTA), image capture is done by Scanning Electron Microscop (SEM) which is equipped by EDX facilities to find out the content in the material coating. Pull off strength testing is carried out to study the adhesive properties of the coating material. Thermal conductivity is carried out to determine the thermal conductivity value of the coating. Alumina materials and talc can be used as fillers for refractory coatings. Small particle size can accelerate the process of homogenization, while particle distribution affects the stress concentration. The ball mill raw material is better to distribute the particles."

"ABSTRAKPada penelitian ini dibuat 2 jenis komposit yang berbeda seratnya (filler-nya) yaitu komposit poliester - serat kenaf dan poliester - serat gelas. Serat kenaf (Hibiscus cannabinus) adalah serat alam banyak ditanam di P.Jawa, harganya murah, biasa dipakai untuk membuat tali dan karung goni. Sebagai matrik dipakai resin poliester tidak jenuh (unsaturated polyester) jenis polimer termaseting, general purpose. Kedua jenis filler disusun dalam bentuk lamina woven roving -ortotropik, selanjutnya komposit diuji kuat tarik dengan Bandar ASTM D 63B type I. Sudut orientasi letak filler bervariasi 0. 15, 30, 45, 60, 75, dan 90. Hasil uji kedua komposit menunjukkan bahwa modulus elastis komposit paling besar pada sudut 6, makin besar sudutnya modulus makin menurun. Hal ini juga berlalu pada Poisson ratio. Untuk uji modulus geser ternyata sudut 45 harganya paling tinggi untuk kedua komposit. Kecuali itu hasil percobaan tersebut bila dibandingkan dengan cara perhitungan kurvanya menunjukkan kecenderungan yang sama atau hasil perhitungan dapat dipakai untuk meramalkan sifat komposit ortotropik. Keunggulan komposit s. kenaf kecuali harganya lebih murah juga komposit ini tidak mengalami penyusutan (shrinkage), jadi bentuknya tetap stabil tidak melengkung. Sedang komposit s. gelas mempunyai sifat susut yang besar sehingga bentuknya tidak dapat stabil. "

"Poliester tak jenuh memiliki aplikasi luas namun mudah terbakar. Aditif halogen awalnya digunakan untuk meningkatkan fire retardancy komposit namun memiliki efek samping negatif terhadap kesehatan. Pada penelitian ini dilakukan sintesis fire retardant composite dengan variasi konsentrasi aditif Al(OH)3/Mg(OH)2 dan filler carbon black. Parameter fire retardancy yang diamati adalah time to ignition (ti), time taken to retard the fire (tr), burning time (tb), dan flammability rating menurut standar UL-94V. Komposisi aditif terbaik diperoleh pada konsentrasi Al(OH)3 40%/Mg(OH)2 10% dengan ti 22,5 detik, tr 6,2 detik, tb 7,8 detik, dan flammability rating V?0. Penambahan filler carbon black sebanyak 2,5% meningkatkan fire retardancy komposit dengan nilai ti 30 detik, tr 1,4 detik, tb 3,5 detik, dan flammability rating V?0. Penambahan aditif dan filler CB mampu meningkatkan stabilitas termal komposit dengan menurunkan mass loss rate (MLR) dan total mass loss. Komposit resin/aditif terbaik (Al(OH)3 40%/Mg(OH)2 10%) memiliki nilai tensile strength sebesar 18,2 MPa dan hardness 51. Sedangkan komposit resin/aditif/filler terbaik (Al(OH)3 40%/Mg(OH)2 10%/CB 2,5%) memiliki nilai tensile strength sebesar 13,9 MPa dan hardness 55.

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Unsaturated polyester resin has wide application but is flammable. Halogen additive was originally used for improving the fire retardancy of the composite but has the negative effects on health. In this research, synthesis of fire retardant composite has been conducted by varying additive Al(OH)3/Mg(OH)2 and carbon black filler concentration. Fire retardancy parameters need to be observed are time to ignition (ti), time taken to retard the fire (tr), burning time (tb), and flammability rating as per UL-94V standard. Additive composition shows the best result at the concentration of Al(OH)3 40%/Mg(OH)2 10% with ti value of 22.5 s, tr 6.2 s, tb 7.8 s, and V-0 flammability rating. Adding carbon black filler of 2.5% improves the fire retardancy of composite with ti value of 30 s, tr 1.4 s, tb 3.5 s, and V-0 flammability rating. Adding of additive and CB filler can improve the thermal stability of composite by reducing mass loss rate (MLR) and total mass loss. The best resin/additive composite (Al(OH)3 40%/Mg(OH)2 10%) has tensile strength value of 18.2 MPa and hardness 51. Whereas, the best resin/additive/filler composite (Al(OH)3 40%/Mg(OH)2 10%/CB 2.5%) has tensile strength value of 13.9 MPa and hardness 55."

"Kemajuan teknologi mendorong berbagai industri untuk menggunakan sambungan material baja tahan karat asutenitik AISI 316L dan baja karbon feritik ASTM A36, yang dapat mengoptimalkan kinerja dan mengurangi biaya produksi. Namun, perbedaan material pada dissimilar welding ini pastinya akan memiliki kecenderungan terjadinya korosi galvanik berkaitan dengan potensial elektrokimia dan komposisi kimia yang berbeda. Salah satu metode penyambungan yang umum digunakan adalah pengelasan TIG yang memakai filler metal untuk menyambungkan kedua material. Pada penelitian ini menggunakan tiga jenis logam pengisi yang berbeda, yaitu ER308LSi, ER309L, dan ER316L. Variasi logam pengisi yang digunakan untuk penyambungan kedua material tersebut telah diteliti dan ditelaah hubungannya terhadap perilaku korosi. Untuk mendukung analisis dan pembahasan penelitian, dilakukan pengujian komposisi kimia, pengamatan mikrostruktur, dan pengujian Linear Polarization Resistance (LPR). Hasil penelitian menunjukkan bahwa logam pengisi ER309L memberikan kinerja korosi yang paling optimal dibandingkan dengan ER308LSi dan ER316L. Analisis hasil penelitian ini mengungkapkan bahwa komposisi kimia, terutama unsur Cr dan Mo, serta fasa mikrostruktur yang terbentuk pada logam pengelasan berperan penting dalam menentukan perilaku korosi, khususnya pada hasil daerah pengelasan.

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Technological advancements are driving various industries to use the joint materials of austenitic stainless steel AISI 316L and ferritic carbon steel ASTM A36 to optimize performance and reduce production costs. However, the material differences in dissimilar welding tend to induce galvanic corrosion due to differing electrochemical potentials and chemical compositions. One commonly used joining method is TIG welding, which employs filler metal to connect the two materials. This study utilized three different filler metals, ER308LSi, ER309L, and ER316L, to examine their effects on corrosion behaviour in the welded joint. Chemical composition testing, microstructure observation, and Linear Polarization Resistance (LPR) testing were conducted to support the analysis and discussion. The results indicated that the ER309L filler metal provided the most optimal corrosion performance compared to ER308LSi and ER316L. The study revealed that chemical composition, particularly the elements Cr and Mo, as well as the microstructural phases formed in the weld metal, play a crucial role in determining corrosion behaviour, especially in the weld area."

"Penelitian mengenai plastik biodegradable sebagai pengganti plastik konvensional telah banyak dilakukan. Pada penelitian ini pati singkong digunakan sebagai matriks plastik dan dikombinasikan dengan hibrid filler yang terdiri dari CMC eceng gondok dan Polivinil Alkohol (PVA). CMC eceng gondok terlebih dahulu disintesis melalui tahap isolasi selulosa eceng gondok dan tahap reaksi sintesisnya. Kedua filler tersebut ditambahkan untuk meningkatkan properti mekanik dari plastik biodegradable. Pertama, gliserol sebagai plasticizer bersama dengan CMC eceng gondok dan PVA akan didispersikan dalam air demineralisasi dengan bantuan ultrasonic processor. Kemudian, pati singkong dimasukkan kedalam campuran lalu dipanaskan sampai kondisi gelatinasinya tercapai. Campuran tersebut dicetak dan dikeringkan menggunakan oven.Hasil penelitian menunjukkan persentase optimum filler yang digunakan agar menghasilkan kekuatan mekanik yang tinggi adalah 30% dari massa pati dilihat dari nilai kuat tarik dan modulus young sampel 1,5 PVA. Komposisi hibrid filler yang menghasilkan bioplastik paling kuat adalah 50% PVA dan 50% CMC eceng gondok dilihat dari hasil uji mekanik sampel 5PVA : 5CMC, dengan kuat tarik 16,19 MPa dan modulus young 197,97 MPa. Hasil soil burial test selama 6 hari, menunjukkan PVA menurunkan laju degradasi dari plastik berbasis pati singkong sebesar 8,3%, sementara CMC eceng gondok meningkatkan laju degradasi plastik berbasis pati singkong sebesar 5,66%.

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Research about the biodegradable plastic as a subtutite of the conventional plastic have been be conducted since a few years ago. In this research, cassava starch are used as the matrix of the plastic and are combined with the hibrid filler that consist of CMC water hyacinth and PVA. CMC water hyacinth first synthesized through a phase of water hyacinth cellulose insulation and synthesis reaction stage. Both of the filler are added to improve mechanical properties of the biodegradable plastic. First, gliserol as a plasticizer together with CMC water hyacinth and PVA are dispersed in demineralized water use ultrasonic processor. Then, cassava starch are poured into the mixture then it is heated until the gelatination condition is reached. That mixture is casted and dried use oven.

The result showed the optimum percentage of filler that is used to produce a high mechanical strength is 30% of the massa of starch views of the value of tensile strength and Young?s modulus of 1,5PVA sample. The composition of hybrid filler that produces the most powerful bioplastic is 50% PVA and 50% CMC water hyacinth seen from the results of mechanical tests of samples 5PVA : 5CMC, with a tensile strength of 16,19 MPa and 197,97 MPa Young?s modulus. results of Soil Burial Test for 6 days, showed PVA reduce the rate of degradation of cassava starch ?based plastics by 8,3%, while CMC water hyacinth increase the degradation rate of cassava starch ? based plastics by 5,66%."