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All Journal Jurnal Teknologi International Journal of Built Environment and Scientific Research Fullerene Journal of Chemistry Journal of Renewable Energy and Mechanics Jurnal Riset Teknologi Pencegahan Pencemaran Industri Engineering, Mathematics and Computer Science Journal (EMACS) International Journal of Innovation in Mechanical Engineering and Advanced Materials
Andrie Harmaji
Institut Teknologi Sains Bandung
Automotive Engineering Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Energy Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mathematics Mechanical Engineering Social Sciences

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Green Construction Material: Polyethylene Waste Reinforce Concrete for Panel Application Andrie Harmaji; Siswanti Zuraida
International Journal of Built Environment and Scientific Research Vol 3, No 1 (2019): International Journal of Built Environment and Scientific Research
Publisher : Department of Architecture Universitas Muhammadiyah Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (347.727 KB) | DOI: 10.24853/ijbesr.3.1.1-6

Abstract

Plastic Composite Panel (PCP) is an innovation in the field of materials that uses recycling plastic waste to construct composite cement panels. This material innovation is one of the solutionto answer environmental problems caused by plastic waste. Some previous studies mostly used plastic waste for concrete aggregates. Thus, making this study different from previous studies. The purpose of this study is to make a prototype of a PCP that is environmentally friendly with panel dimensions sample of 100 x 30 x 10 mm thick. The method used is an experimental test using materials in the form of polyethylene terephtalate (PET) from used water bottle and cement waste as well as testing its physical and mechanical properties carried out in the laboratory. Variations in PET used for testing materials are 0- 20%. In addition to mechanical properties, specific gravity and porosity test is carried out. The best results shows that 5% PET addition to cement paste increase the flexutral strength to 4.47 MPa compared to control sample which has 3.26 MPa. Porosity test shows that addition of 10% PET reduce the density of PCP to 63.64% compared to control sample that has 44.44%.
Seawater as Alkali Activator in Fly Ash Based Geopolymer Andrie Harmaji
Engineering, MAthematics and Computer Science (EMACS) Journal Vol. 4 No. 2 (2022): EMACS
Publisher : Bina Nusantara University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21512/emacsjournal.v4i2.8322

Abstract

Indonesia as a maritime country in the world with 66% of its territory consists of maritime territory. A lot of potential that can be exploited, such as sea water. XRD characterization results indicate that the sea water from Tanjung Priok, North Jakarta, Indonesia has a compound Halite (NaCl) and Bassanite (CaSO4.5H2O) in the salt form. These compounds are alkaline thereby can influence the compressive strength of the geopolymer. Geopolymer is made up of aluminosilicate precursors which are activated by the alkaline activator solution, which usually combines sodium silicate and sodium hydroxide. The precursor material is waste from the coal based power plant called fly ash that produce 219.000 tonne per year and still underutilized but potentially as an alternative to cement. In this study, seawater was used to substitute the sodium hydroxide in alkali activator as an effort to reduce the manufacturing cost of Geopolymer. Geopolymer prepared by mixing fly ash as a precursor, silica sand as aggregates, with activator, then casted and cured by immersion. After 28 days compression test was conducted to measure the strength of resulting geopolymer. The sample consisted of a mixture of fly ash, silica sand, waterglass, and seawater produces strength of 16.60 MPa. X-Ray Diffraction characterization was conducted to study the compound formed from precursors activated with seawater alkali activator. Resulting diffractogram indicate the formation of anorthite compound as proof of Geopolymerization has been successfully occured.
PROPERTIES AND MORPHOLOGICAL OF MORTAR CONTAINING USED ENGINE OIL Andrie Harmaji; Andikah Willy Ramadhan
International Journal of Innovation in Mechanical Engineering and Advanced Materials Vol 4, No 1 (2022)
Publisher : Universitas Mercu Buana, Prodi S2 Teknik Mesin

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (393.306 KB) | DOI: 10.22441/ijimeam.v4i1.15132

Abstract

Engine oil has an important role in the design and operation of all automotive engines. Used engine oil is a waste product produced in high quantity in the workshop garage which commonly found in most cities in Indonesia. The utilization of used engine oil has shown potential as retarder by reduce the setting time of mortar. In this study mortar was made by mixing cement,light aggregate, water, and engine oil both new and used as admixture ranged 0-1%. Mortar sample treatment is carried out at room temperature. The samples were tested for setting time and compressive strength after 3, 7 and 28 days curing. Scanning Electron Microscope characterization was carried out to to find out the morphological structure of resulting mortar. Results shown that the mortar with the addition of 0.75% used engine oil has the highest compressive test result of 9.31 MPa when the mortar reached 28 days compared to mortar without engine oil addition has a compressive test result of 7.546 MPa. SEM Images shown there are more ettringite presents in mortar with used engine oil addition.
MORPHOLOGICAL AND PROPERTIES OF PORTLAND-COMPOSITE CEMENTS WITH CLASS C FLY ASH Andrie Harmaji; A. Fadillah
International Journal of Innovation in Mechanical Engineering and Advanced Materials Vol 4, No 2 (2022)
Publisher : Universitas Mercu Buana, Prodi S2 Teknik Mesin

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/ijimeam.v4i2.17036

Abstract

Portland-composite cements (PCC) were prepared with partial substitution of 5 to 25% of class C fly ash, obtained from East Java steam power plant. Properties of the composite cements was evaluated, through the setting time (initial and final) and compressive strength (3, 7, and 28 days) compared with control PCC. Setting time is retarded in Portland-composite cements with higher fly ash content. The retardation is highest in PCC with substitution of 25% fly ash. Lower compressive strength is obtained after 3 and 7 days of curing for PCC with 5-25% fly ash substitution in comparison with control cement, since pozzolanic reaction still did not show its effect. After 28 days, compressive strength was higher than that for control cement because pozzolanic reaction show its effect, highlighted by compressive strength increase of PCC substituted by 5% and 10% fly ash, 16.48 MPa and 16.52 MPa, respectively. This attributed to the differences in the pozzolanic activity of the applied fly ash. The compressive strength increase was explained by Scanning Electron Microscope (SEM), which shows that PCC with substitution of 10% fly ash had more Tobermorite presented compared to control cement.
Mechanical And Microstructural Assessment Of Synthetic Aluminosilicate Based Geopolymer Dental Material Andrie Harmaji; Oqy Diadara Putri; Bambang Sunendar
Jurnal Kimia Fullerene Vol 7 No 2 (2022): Fullerene Journal of Chemistry
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.37033/fjc.v7i2.425

Abstract

Orthodontic treatment with fixed brackets was performed to transmit the pressure from the wire to the periodontal tissues to produce tooth movement. Ceramic material can be used not only to improve the aestheticness but also maintains good mechanical properties. This study aims to determine the mechanical properties and morphological of synthetic aluminosilicate based geopolymer for aesthetic orthodontic brackets applications made by synthesizing alumina (Al2O3), silica (SiO2), and magnesia (MgO) from sol-gel method. Geopolymer nanocomposite was made by activating synthetic precursor with alkali solutions consists of sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) solution which has molarity variations of 8M (GP-8M) and 14M (GP-14M). The test results using an X-Ray Diffractometer (XRD) showed that the crystalline phase of (Mg,Si)Al2O4 spinel was successfully presented in the synthesized nanocomposite. The average hardness test results using the Vickers hardness tester for Geopolymer Nanocomposite with 8M and 14M alkali activator were 259.15 and 298.90 VHN, respectively. The results of the surface morphological characterization using Scanning Electron Microscope (SEM) of the samples showed the porosity of GP-14M was smaller than GP-8M, which explains the hardness test value difference. This shows Geopolymer is a potential material for orthodontic brackets manufacture.
Effect of Quenching Medium and Tempering Temperature on Microstructure and Hardness of JIS SUP 9 Steel: Pengaruh Media Pendingin dan Temperatur Tempering pada Mikrostruktur dan Kekerasan Baja JIS SUP 9 Andrie Harmaji; Akhmad Ardian Korda; Rama Ramadhan; Satrio Pambudi
Journal of Renewable Energy and Mechanics Vol. 6 No. 01 (2023): REM VOL 6 NO 01 2023
Publisher : UIR PRESS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25299/rem.2023.vol6.no01.10973

Abstract

JIS SUP 9 steel is one of the materials commonly used for suspension components in motorized vehicles with medium carbon steel base material. It must have good hardness and toughness so that failure does not occur during operational. This research was conducted to increase the hardness of JIS SUP 9 Steel through a heat treatment and various quenching media. The heat treatment was carried out with 830-880ºC temperature with a holding time of 7 minutes then cooled using water and oil. After treatment, tempering was carried out with a holding time of 7 minutes and then cooled in room temperature. Hardness testing was carried out using Microhardness Vickers and then the microstructure was observed using an Olympus Metallurgical Microscope. The results show that heat treatment followed by rapid cooling increases the initial hardness of JIS SUP 9 (229 VHN) steel. The decrease in hardness after the tempering process will be higher with increasing tempering temperature. The results of the microstructure of the sample without heat treatment showed pearlite and ferrite phases. After heat treatment, tempered martensite, residual austenite and carbide phases appear. It can be concluded that changes in the microstructure affect the hardness of JIS SUP 9 steel.
Impact of Reduced Activator Concentration and Curing Method on Compressive Strength of Metakaolin/Fly Ash-based Geopolymer Mortar Andrie Harmaji; Alexander Syahlendra Haimir; Bambang Sunendar
Jurnal Riset Teknologi Pencegahan Pencemaran Industri Vol. 14 No. 1 (2023)
Publisher : Balai Besar Standardisasi dan Pelayanan Jasa Pencegahan Pencemaran Industri

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21771/jrtppi.2023.v14.no1.p19-28

Abstract

The demand for cement is increasing each year, but the manufacture of 1 tonne of cement produces an equal number of carbondioxide (CO2) gas which is directly related to the increase in global warming. Therefore, we need a substitute material, namely geopolymer. This material has relatively superior properties compared to cement. However, one of the drawbacks of geopolymers is that the production costs are relatively more expensive compared to the manufacture of pre-cast cement because it requires chemical solutions such as sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) to activate the precursor. This research was conducted to replace a specific ratio of alkali activator with water to reduce the use of alkaline hydroxide solutions and sodium silicate while reducing production costs. The experiment was carried out by replacing the activator solution with water at a certain amount with a different curing method. Mechanical properties, X-Ray Diffraction (XRD), and Fourier Transform Infrared (FTIR) spectroscopy characterization were used to analyze the effect of additional water in geopolymer. The compressive test result shows that the maximum water content that can replace the activator solution is 20% by activator mass for fly ash-based geopolymers and 30% by activator mass for metakaolin-based geopolymers, with sealed and bare curing conditions before the compressive strength was decreased sharply. Substitution of 10% water in fly ash-based geopolymer increases the compressive strength to 17.20 MPa. Compressive test results and characterization showed that the optimal curing condition for fly ash-based geopolymer was sealed curing and bare curing for metakaolin-based geopolymer. The strength increase is due to O-C-O bonds representing sodium carbonate (Na2CO3), which affects the compressive strength of fly ash-based and metakaolin-based geopolymers.
FLEXURAL STRENGTH OF PINEAPPLE LEAF FIBER REINFORCED METAKAOLIN ZIRCONIA CARBONATE APATITE GEOPOLYMER COMPOSITE Andrie Harmaji; Susanti Nurfadhila; Bambang Sunendar
Jurnal Teknologi Vol 15, No 2 (2023): Jurnal Teknologi
Publisher : Fakultas Teknik Universitas Muhammadiyah Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24853/jurtek.15.2.237-246

Abstract

Developments in the materials engineering have encouraged the incorporation of minerals such as kaolin, zirconia, and carbonate apatite, and natural materials. Indonesia, which has a tropical climate, is overgrown with pineapple plants. Geopolymer is a brittle ceramic material so it is necessary to increase its flexural strength value for composite application. Pineapple leaf fiber can be used as reinforcement in geopolymer composites. This study aims to analyze the effect of adding pineapple leaf fiber (Ananas comosus (L.) Merr.) to the mechanical properties and morphological characteristics of metakaolin-zirconia-carbonate apatite-based geopolymer composites. The use of chitosan coupling agent as a binder between the matrix and filler. The research sample consisted of 4 groups with a total of 5 samples in each group. Fiber varied 0-4% in Geopolymer Composites. Geopolymer Composite samples were tested for flexural strength and Scanning Electron Microscope (SEM). The test results showed that the addition of pineapple leaf fiber increased the flexural strength of the geopolymer composite. The composite without the addition of fiber had a flexural strength of 11.24 MPa, while the addition of 1%, 2.5%, and 4% pineapple fiber resulted in a flexural strength of 20.71 MPa, 11.57 MPa, and 11.01 MPa. The results of the SEM test show a picture of the void with varying sizes. The SEM Images of composite with the addition of 4% pineapple fiber showed the formation of Na2CO3 which explained the decrease in flexural strength compared to the sample without pineapple fiber addition.
Co-Authors A. Fadillah Akhmad Ardian Korda Alexander Syahlendra Haimir Andikah Willy Ramadhan Bambang Sunendar Bambang Sunendar Oqy Diadara Putri Rama Ramadhan Satrio Pambudi Siswanti Zuraida Susanti Nurfadhila