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Rice husk is waste from rice milling which can pollute the environment. Current pollution problems are also in the form of plastic raw materials, to minimize plastic waste as an alternative by utilizing rice husks that are easily available in all regions in Indonesia because Indonesian staple food rice is made as a composite material natural. Through the utilization of rice husk waste as a natural composite raw material by the hot press process, this study aims to make small plate product molds. In this study using a static simulation method using mechanical and thermomechanical load variations and thermal distribution simulation on Solidwork with mold dimensions of 200x200x50 mm using Stainless Steel with variations in wall thickness of molds 10mm, 15mm, 20mm and using variations of 1000N, 2000N, 3000N to test the strength of mold thickness parameters. The results of static and thermal simulations conducted concluded that the most perfect mold thickness for thermomechanics is 10mm because it has a maximum value than other thickness variations, while the results of thermal simulation not significant of temperature. [ABSTRACT FROM AUTHOR]

Plastic waste is one of the problems that requires more attention. Apart from the large amount, plastic waste is also very difficult to decompose. One solution to solve this problem is to utilize plastic waste to be recycled into useful products, one of which is roof tiles. This research aims to see whether making plastic roof tiles is feasible as a business. Determination of feasibility analysis is carried out based on three aspects, namely technical aspects, financial aspects and marketing aspects. Based on the results of the analysis of the technical aspects, the selling price of the roof tile is Rp.5,288, which means that the price of plastic roof tiles is relatively cheaper than the price of clay tiles at Rp.6,000 Based on the financial aspects, the results show a positive NPV, IRR of 58%, PP for 1 year, BEP unit of 695,510 units and BEP price of Rp.365,882,218, which means that financially, this roof tile making business is quite promising. In marketing, Indonesia has several areas that often experience earthquakes, this area is an area with great potential to utilize plastic roof tiles because plastic roof tiles are more resistant to earthquakes or other natural disasters than soil tiles. Based on the three feasibility analyses, it can be said that the plastic tile business has the opportunity to be realized. [ABSTRACT FROM AUTHOR]

Cold water pipes (CWP) used in ocean thermal energy conversion installations must be able to withstand wave loads, deep seawater currents, and the weight of the pipe itself. Seawater currents shake the cold water pipe in a horizontal direction which causes the pipe to experience bending loads and the structure of the pipe material will experience tensile-compressive loads. So that it is required the properties of pipe material such high strength and better flexibility that it is not easily broken. In the material selection, High Density Polyethylene cold water pipe material reinforced with glass fiber is suitable for CWP material and corrosion-resistant as well. The formation of glass fiber reinforced High Density Polyethylene composite materials, which using hot press molds to obtain better results of combining High Density Polyethylene fiber and matrix and increasing resistance to tensile loads. The results of the tensile test of the material formed by hot pressing from High Density Polyethylene composite with fiberglass, indicating that the toughness and strain of the material with short fibers were better than that of long fibers. In short fiber, there is an increase in tensile strength by 2.7%, toughness with 42%, and strain by 35.2%. This increase in toughness and strain is required for CWP, in order to the use of short fibers becomes more appropriate for CWP construction. The improved toughness of this short fiber fiberglass provides an excellent basis to produce cold water pipe materials in Ocean Thermal Energy Conversion installations. The mechanical properties of short fibers High Density Polyethylene composites will be able to accept tensile loads from currents, waves and weight from the cold water pipe itself in the cold water pipe construction. [ABSTRACT FROM AUTHOR]

This paper presents the numerical simulation of hot press forming process by introducing nanocoolant compared with chilled water into the cooling channel system of HPF tool. By using thermal analysis, the heat distribution between heated blank and tools are evaluated. The thermal analysis results show that the average enhancement of nanocoolant cooling rate is measured to be 30.2% higher compared with chilled water. The simulation data are validated with experimental hot press forming results. [ABSTRACT FROM AUTHOR]

Fabrication PVDF films have been made using Hot Roll Press. Preparation of samples carried out for nine different temperatures. This condition is carried out to see the effect of Roll Hot Press temperature on the size of the crystallite of PVDF films. To obtain the diffraction pattern of sample characterization is performed using X-Ray Diffraction. Furthermore, from the diffraction pattern is obtained, the calculation to determine the crystallite size of the sample by using the Scherrer equation. From the experimental results and the calculation of crystallite sizes obtained for the samples with temperature 130 °C up to 170 °C respectively increased from 7.2 nm up to 20.54 nm. These results show that increasing temperatures will also increase the size of the crystallite of the sample. This happens because with the increasing temperature causes the higher the degree of crystallization of PVDF film sample is formed, so that the crystallite size also increases. This condition indicates that the specific volume or size of the crystals depends on the magnitude of the temperature as it has been studied by Nakagawa. [ABSTRACT FROM AUTHOR]

In this research, corrosion properties of assorted types of PTFE were examined under concentrated strong acid and high temperature condition. The most optimum type from the test results will then be used as a coating material for high temperature reactors using the hot press method, which are intended to be used as a coating on tin sulfate production reactor. PTFE was examined using sulfuric acid 96% by immersion and steam method at 250°C. The result shows that the PTFE sheet possesses the least affected by concentrated sulfuric acid corrosion, with 0.0116% corrosion per hour. In addition, PTFE sheet has been successfully coated on high temperature reactor. [ABSTRACT FROM AUTHOR]

Titanium diselenide (TiSe2) alloy was prepared using solid state reaction method and hot press sintering. The effects of hot press sintering temperatures on TiSe2 were studied on the thermal transport properties of the material. As grown material shows pure TiSe2 phase and layer structure. Increasing sintering temperature results in reduced electrical resistivity ρ whereas the Seebeck coefficient, α show no significant relative change. Reduced electrical resistivity may be attributed to the increased crystalline nature. This results in improved power factor showing the optimum condition for producing better TiSe2 thermoelectric material. [ABSTRACT FROM AUTHOR]

Wood Plastic Composite (WPC) is a composite resulting from mixing wood powder/fiber with a thermoplastic matrix. This study made WPC by mixing cantala fiber powder with recycled high-density polyethylene (rHDPE) thermoplastic. WPC manufacture is done by a single screw extruder and hot press. The extruder converts a mixture of cantala powder and rHDPE into granules which are then further processed in a hot press into composite sheets. The process temperature in the extruder is varied from 130°C, 140°C, and 150°C. Composite sheet manufacture is carried out at a temperature of 150°C and a pressure of 50 bar for 25 minutes. The effect of extruder temperature on tensile properties, density, and morphology of rHDPE/cantala composites has been studied. The results showed that the extruder temperature 150°C could produce a composite with the highest tensile strength of 29.10 MPa with the lowest density of 1.2 kg/m3. The morphological observations showed that the temperature of 150°C was able to produce a uniform mixture of rHDPE and cantala powder. [ABSTRACT FROM AUTHOR]

Titanium diselenide (TiSe2) alloy was prepared using solid state reaction method and hot press sintering. The effects of hot press sintering temperatures on TiSe2 were studied on the thermal transport properties of the material. As grown material shows pure TiSe2 phase and layer structure. Increasing sintering temperature results in reduced electrical resistivity ρ whereas the Seebeck coefficient, α show no significant relative change. Reduced electrical resistivity may be attributed to the increased crystalline nature. This results in improved power factor showing the optimum condition for producing better TiSe2 thermoelectric material. [ABSTRACT FROM AUTHOR]

"Polymer-in-ceramic" electrolytes with high ceramic content have emerged as favorable candidates in all-solid-state lithium batteries. Here, we report the fabrication of composite pellet of LiSn2(PO4)3 and PEO-LiClO4 using hot press technique. Structure, microstructure, and the conductivity behavior of the composite sample were investigated using x-ray diffraction, fourier-transform infrared spectroscopy, scanning electron microscopy, and complex impedance spectroscopy. The composite pellet exhibited room temperature DC conductivity and the activation energy around 3.73×10−5 S cm−1 and 0.378 eV, respectively. The present investigation confirms that the addition of polymeric salt is not only helpful in improving the ionic conductivity but also circumvents the problems associated with poor sintering behavior observed in NASICON-type compounds. [ABSTRACT FROM AUTHOR]

Temperature dependent ionic conductivity (σ), ionic mobility (μ), and mobile ion concentration (n) of the hot-pressed Solid Polymer Electrolytes (SPEs): (1-x) PEO: x NaBr, where 0 < x < 50 in wt. %, has been reported. SPE films have been casted using a hot-press technique in place of the traditional solution cast method. A conductivity enhancement of the two orders of magnitude was achieved in SPE film composition: (70PEO: 30NaBr) at room temperature and this has been referred to as Optimum Conducting Composition (OCC). To determine the activation energy (Ea), energy of migration (Em) and energy of formation (Ef) temperature dependent studies of SPE OCC have been carried out with the help of various experimental procedures. [ABSTRACT FROM AUTHOR]

We have synthesized bismuth telluride compound using mechanical alloying and hot press sintering method. The phase formation, crystal structure was evaluated by X-ray diffraction and Raman spectroscopy. The scanning electron microscopy images indicated sub-micron sized grains. We observed low value of thermal conductivity 0.39 W/mK at room temperature as a result of grain size reduction by increasing deformation. The performance of the samples can be improved by reducing the grain size, which increases the grain boundary scattering. [ABSTRACT FROM AUTHOR]

This research investigates the tensile, flexural and impact properties of sugar palm fibre (SPF) reinforced polypropylene (PP) composites. Composites were developed by using internal mixer and hot press machine, and were fabricated with containing of 10, 20 and 30% weight of the sugar palm fibres. Two types of treatments named mercerization and compatibilizing agent are used to improve the adhesion between fibre and matrix for composites with 30%wt. of sugar palm fibre. Mercerization is the fibre surface treatment that soaking the SPF in alkaline solution with 2%, 4% and 6%wt. of alkali concentration. Maleic anhydride polypropylene (MAPP) was selected as compatibilizing agent with 2%, 3% and 5%wt. loading. Then, the mechanical properties of composites were evaluated to study the tensile, flexural impact properties based on the ASTM D638, ASTM D790 and ASTM D6110 standards respectively. The results showed that the increase of SPF loading in PP matrix improved the tensile and flexural properties of the composites. Meanwhile for the impact strength, it shows a decreasing order with increasing fibre loading. The effect of both treatments also showed the improvement for every mechanical properties of the composites. [ABSTRACT FROM AUTHOR]

Plastic waste has become one of the critical environmental issues for all people on earth. Therefore, how to overcome that problem is become a highly demanding effort. In this research, we discuss about the recycling process of plastic waste using a simple method named hot press method. The plastic waste resources used are LOPE, PET, Melamine, and Bakelite. The outcome of this research is a paving block that expected to be complied to the National Standard of Indonesia. Sequence analysis addressed to the specimen are including SEM, FTIR, density test, compression test, and water absorbability test. The highest compression stress of the specimen is 24.13 Mpa for 15%wt of bakelite addition. The lightest density of the specimen is 1.0042 gram/cm3 that attributed to the specimen with 15%wt of bakelite addition. The resulted paving block in this research can be categorized as B type based on SNI 03-0691-1996 and SNI 03-3449-2002 standard. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the phase composition, parameters of fine crystalline structure and mechanical properties of aluminum-based composites, produced by hot pressing with different synthesis temperatures and isothermal times. For synthesis of composites we used powder mixture of aluminum (particles size 700 nm) and carbon powder in a form of nanodiamonds (size 4 nm). It has been shown that after hot press processing a nanophase (crystallites size 25 nm) of aluminum carbide was formed. Regardless of the synthesis temperature for the maximum holding time of powder mixtures, the density of hot-pressed compacts is about 2.2-2.37 g/cm³. In particular, the value of bending strength of composite samples with a density of 2.37 g/cm³ ranges from 350 to 480 MPa. In the nonporous state, the bending strength of the composites may reach 920 MPa. [ABSTRACT FROM AUTHOR]

Composites from natural fiber reinforcement are developed as the alternative sheet materials of plastic composite for small-size bodywork parts in automotive industries. Kenaf fiber is selected as the reinforcement of plastic composite. Press forming of Kenaf-Polypropylene is experimentally produced in this study. The aim of this study is to obtain the optimal factor of the process of sheet forming of Kenaf-Polypropylene. The Kenaf delignified is cut into 5 cm lengths and distributed on the surface of Polypropylene sheet for 3 and 5 ply layers. The layers of Kenaf-Polypropylene then pressed by hot press at 190 and 210°C, 40 and 50 bar, for 3 and 5 minutes. However, there are limitations in handling multi responses in design of experiments. The application of the fuzzy logic theory to the grey relational analysis may further develop its performance in solving multi-response problems for process parameter optimization. The layer of Kenaf and Polypropylene, temperature, the duration of hot press and pressure are factors that affect the process. The result of experimental investigation and as well as analysis, shows that the best combination values were 3 ply layer, 210°C, 5 minutes of hot press and 50 bar. [ABSTRACT FROM AUTHOR]

The aim of this study was to obtain ceramic materials by using hot pressing from superhard and refractory materials. This paper discussed the microstructure and microhardness of ceramic tablets obtained from mixtures of boron carbide, hafnium carbide and alumina oxide by hot pressing. It is shown that with the hot pressing parameters used, active sintering occurs when shrinkage is more than thermal expansion. Sintered tablets of alumina oxide and hafnium carbide reach hardness corresponding to solid material. Submicron boron carbide has not enough hardness because the temperature parameters were not maintained for a period of time. [ABSTRACT FROM AUTHOR]

The production process in palm flour industry in addition to producing palm flour, this industry also produces waste, one of which is a solid waste in the form of fiber powder which still contains starch. The waste still has the potential to become a product that has added value. This research will discuss the potential of palm fiber powder waste into biodegradable foam (biofoam) and its characterization. Making biofoam using solid waste from the palm flour industry with an addiotional source of cellulose, rice straw. Biofoam formulation was carried out in 9 series of experiments with an additional ingredient as bounding agent, Polyvinyl Alcohol also Magnesium Stearat for prevent sticking to the molding when pressing process. The manufacturing process used thermopressing technology, by mixing the ingredients according to the formulation and then pressing using a hot-pressing machine at a temperature of around 145-165 0C in 30 minutes. The experiment of making biofoam was carried out with nine formulations that produced the best results, namely sample C5. Sample C5 was made from palm pulp waste with a content of 30%, straw with a content of 15%, PVA and Aquades with a content of 25%, and magnesium stearate with a content of 5%. Characteristics of the results of physical, mechanical, and biodegradation properties for C5 biofoam obtained water absorption of 68.674%, tensile strength of 2.297 MPa, elongation of 17.040%, Young's modulus of 0.219%, and a degradation rate of 67.468% with burial for 7 days. [ABSTRACT FROM AUTHOR]

Polycrystalline SrxTiSe2 (x = 0.04, 0.14, 0.2) alloy was prepared using solid state reaction method and hot press sintering. The effects Sr content were studied on the thermal transport properties of the material. As grown material shows pure TiSe2 phase. Increasing the strontium content reduces thermal conductivity of the material. This is attributed to large number of interfaces and weakly bound Sr atom which acts like a phonon scatterer. [ABSTRACT FROM AUTHOR]

The components of the sandwich structure using materials not environmentally friendly because it cannot be recycled after its useful life runs out. This research is focused on the effect of core thickness on the bending strength of the composite sandwich-rHDPE cantula. The variation of thickness is 10mm, 15mm, and 20mm. Skin is made only of powder recycled-High-Density Polyethylene (rHDPE), while the core is made of fiber cantula and rHDPE. The process of making skins and cores made using a hot press. The parameter process use includes a process temperature of 170°C, holding time 15minutes and the pressing pressure of 50bar. Dimensions and bending testing refer to ASTM C 393 for the dimension and compression testing method. The results showed that variations thickness core effect on the bending strength and compression strength of the composite sandwich-rHDPEcantula. The highest bending strength of 23,56Mpa MPa was obtained with core thickness 20mm. [ABSTRACT FROM AUTHOR]

The present work involves the processing, mechanical and dry sliding wear behavior of silicon carbide (SiC) particles with magnesium (Mg) matrix. The amount of SiC reinforcement was 10 and 20 vol. %. The composites were produced using hot pressing at 5 MPa, 640 °C for 30 min. The density of Mg-SiC10 vol. % and Mg-SiC20 vol. % composites are 1.81 and 1.98 g/cm³, respectively. Microhardness and compressive strength of the composites was increased as the SiC content increases. Dry sliding wear test carried out at different load, sliding distance and sliding velocity having coefficient of friction in the range 0.39-0.53 and specific wear rate of 1.7×10-6cm³/N m for Mg-SiC20 composites. [ABSTRACT FROM AUTHOR]

Composite friction brake is a vital part of braking system which serves to reduce the speed of vehicle. To fulfill the requirement of brake performance, composite friction brake must have friction and mechanical characteristic as required. The characteristics of composite friction brake are affected by brake material formulation and manufacturing parameter. In the beginning of hot molding, intermittent hot pressing was carried out to release the gases that consist of ammonia gas and water vapor. In composite friction brake, phenolic resin containing hexamethylenetetramine (HMTA) is often used as a binder. During hot molding, the reaction of phenolic resin and HMTA forms ammonia gas. Hot molding also generates water vapor because raw materials absorb moisture from environment when they are placed in storage. The gas release in hot molding is supposed affecting mechanical properties because it avoid entrapped gas in composite, so that this research investigated effect of gas release on flexural strength. Manufacturing of composite specimen was carried out as follow: mixing of raw materials, cold molding, and hot molding. In this research, duration of intermittent hot pressing and number of gas release were varied. The flexural strength of specimen was measured using three point bending test. The results showed that flexural strength specimens that were manufactured without gas release, using 4 times gas release with intermittent hot pressing for 5 and 10 seconds were not remarkably different. Conversely, hot molding using 4 times gas release with intermittent hot pressing for 15 seconds decreased flexural strength of composite. Hot molding using 2, 4, and 8 times gas release with intermittent hot pressing for 10 seconds also had no effect on increasing flexural strength. Increasing of flexural strength of composite was obtained only by using 6 times gas release with intermittent hot pressing for 10 seconds. [ABSTRACT FROM AUTHOR]