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To maintain the structural integrity of fuel elements for a high temperature gas-cooled reactor (HTGR) under beyond design conditions, strong and oxidation-resistant fuel elements should be further developed. The HTGR fuel elements employ a hot-pressed silicon carbide (SiC)/carbon (C) mixed matrix to improve the oxidative resistance. Hot-press conditions such as pressure, temperature, and duration would be one of the factors that affect the strength of the HTGR fuel elements. To identify the optimal hot-press conditions for preparing the high-strength fuel elements, modeling their effects on the mechanical-strength properties of the HTGR fuel elements should be evaluated quantitatively. In this study, the response–surface model, which represents the relationship between the hot-press conditions and the mechanical-strength properties, has been constructed by introducing statistical design of experiments approaches. The model estimated the optimal hot-press conditions for producing the high-strength fuel elements. We discuss the model’s validity by comparing its predictions with experimental observations.

The effect of hot-press sintering temperature on density of tungsten heavy alloys is presented in this paper. The experiments were performed for the WNi5Cu3 samples of W-Ni-Cu heavy alloy system. The hot-press sintering temperature was ranged from 1300 to 1440 °c with a constant applied pressure of 40 MPa. Subsequently, the sintered samples were annealed at 1000 °c in acgon atmosphere during 3 h. The results showed that the obtained heavy alloys had maximum density of 17,427 g.cm3 and final particle size around (10 + 15) mm. The obtained results met the requirement for fabrication of small balanced parts for aeronautical industry.

A hot press process was used as a technique to pound a polyamide type of polymer of a thickness (2mm) to stainless steel AISI 316L of the thickness (1mm). A hybrid joint of dissimilar material was accomplished by a hot press bonding process. During the joining process, three different parameters of process were used: processing temperature of 175, 170 and 165°C, processing pressure of 3, 6 and 9 bar and time of 1.5, 3 and 4.5 min. The surface of stainless steel was prepared and treated by a mechanical treatment (surface grinding) to improve the wettability to increase the shear strength. A shear tensile, scanning electron microscope (SEM) and energy dispersive spectrometry (EDS) tests were used to investigate and examine the joint (bounding) specimens. The Minitab program was used to analyze the effect of the parameters of the joining process on the joint properties. The maximum and minimum values of shear force are exhibited at a processing temperature of 165°C, applied pressure of 6 bars and processing time of 1.5 minutes; the minimum shear force was found to be 675 N, while the maximum shear force was 2182 N at a processing temperature of 175°C, applied pressure of 6 bars and processing time of 3 minutes. The tested joints failed by an interfacial shear and necking in the polymer side with a ductile fracture. The joining process occurred through a mechanical interlocking between the molten polymer and the treated surface of the steel specimen. The average thickness of the joining line for the tested specimens was 8µm.

A facing clutch manufacturer in Surabaya, Indonesia, PT. X uses 20 hot press machines to produce the facings. The required heating process is provided by heat transfer oil (HTO), which is heated by natural gas burned in a heater. PT. X wants to reduce its natural gas consumption. The assessment started with checking the insulation on the piping system, measuring the temperature in the hot press machines, and measuring the HTO flow rate. The insulation in the piping system is in good condition. From the measurement, it was found that the HTO flow rate is adequate and fits the need of the heating process. Another finding is that the surface temperature of the lower plate in shaft no. 4 is the lowest than in the other shafts. The existing (asbestos) insulation from the lower bed in shaft no 4 to the hydraulic component is only 3 mm thick. This is not enough to prevent heat loss from the bed in shaft no. 4. The new 18-mm asbestos replaced the old asbestos. The replacement shows that the temperature at the mold surface at shaft no. 4 increased from 162.6°C to 170.9°C on average for MC-02 and from 166.7°C to 173.1°C on average for MC-03. Another achievement obtained is that the natural gas consumption was reduced by around 7.3% or 39 MMBtu/month, or equivalent to reducing 0.312 metric tons of CO2 per month. This is a simple effort to use less energy to protect our environment.

In the study, the bonding strength of phenol-formaldehyde (PF) adhesive on plywood under different hot press temperature and time was evaluated. A mechanical mathematical model was established to a...

Hot-press compression molding was used to resinify a renewable source-derived linear 1,4-linked β-D-glucan copolymer, i.e., konjac glucomannan (KGM), via the generation of reactive aldehyde groups ...

The microstructures and properties of powder metallurgy Ti-45Al-10Nb (at.%) alloys fabricated by vacuum hot pressing consolidation of milled powder have been investigated. Under the sintering condi...

An aluminophosphate adhesive was used as the binder in plywood. The hot-pressing parameters of aluminophosphate adhesive-based plywood (APPs) including hot-press temperature (A), time (B), and pressure (C) were optimized using response surface methodology. Results indicated that the hot-press temperature was the most dominant factor. The maximum bonding strength of 1.98 MPa was found with an optimal parameter of 171 °C (hot-press temperature), 7.5 min (hot-press time), and 1.0 MPa (hot-press pressure). Additionally, the chemical reaction mechanism between aluminophosphate adhesive and wood fibers was characterized by X-ray photoelectron spectroscopy (XPS). Results showed that good interaction was generated between wood fibers and adhesives through their surface functional groups. In conclusion, the optimized pressing conditions of plywood significantly improved bonding strength of APPs.

This study was conducted to investigate the effect of low-density polyethylene on the microstructural and mechanical properties of 3105 aluminum composites produced by the continuous hot-press method. This production method ensures superior flatness to the composite and excellent peel strength between the composite plies. To this end, the bond between AA3105 and low-density polyethylene was initially characterized using a T-Peel stripping test. Tensile tests were performed on AA3105, low-density polyethylene and 3105 aluminum composites for determining mechanical behavior. A scanning electron microscope was used to characterize the cross-sectional cuts of the 3105 aluminum composite specimens obtained from the tensile tests. The microstructural analysis shows that low-density polyethylene and AA3105 exhibit a good interfacial adhesion bond before the fracture of the first AA3105 sheet. The results of the tensile tests clearly show that the uniform elongation at maximum load (Ag) of the 3105 aluminum composite is higher than that of AA3105. Furthermore, AA3105 exhibits negative strain rate sensitivity due to dynamic strain aging while 3105 aluminum composite exhibits a higher strain-hardening exponent than AA3105. Due to the higher strain rate sensitivity and strain hardening exponent, the 3105 aluminum composite exhibits higher formability than AA3105. This is of crucial importance for the manufacturing process.

The purpose of this study is to develop a control scheme for the hydraulic proportionalsystem using PID function on Mitsubishi PLC Q series, which can rapidly control the pressurein a hydraulic cylinder with very short stroke. The mathematical model of the control system isestablished according to the principle of the electro-hydraulic system. Considering the mentionedcharacteristics, simulation of the system modelling will be established to know the systemresponse. In order to improve the control precision of the hydraulic hot-press system, theMitsubishi PID controller are designed by selecting appropriate tuning parameters. Their controlperformances are analysed in time domain respectively. The variation of PID controllerconfiguration will be conduct to know the better model for this system controller. The validityof the proposed control scheme is confirmed through the experiments to verify the rationality ofthe theoretical model. The results show that the Mitsubishi PID and the ideal PID give the sameresult for the tuning parameter resulted from simulation. And also the experiment give the betterstability in the 3 different pressure set value that conduct by author.

Dense boron carbide bearings with a central through hole were fabricated by hot-press sintering. When the sintering temperature was above the critical grain growth temperature, an increase in the applied pressure at 2100 °C caused a distinct abnormal grain size region. Two grain growth mechanisms were explored; normal grain growth (NGG) is controlled by a grain boundary diffusion mechanism whereas the abnormal grain growth (AGG) pattern abides by the ‘Bose–Einstein’ grain growth law.

In this study, a microwave hot press sintering (MHPS) strategy was developed for metal-bonded diamond composites (MBDC). The main focus was on the MHPS process of Fe60Cu40 pre-alloy bonded diamond composites. The temperature rise characteristics of the metal powders were obtained within a microwave field. Further, the composition change law of the composites was determined during the sintering process by analyzing the properties and microstructure of the composites. The successful development of this strategy will provide a reliable reference for the application of microwave sintering in the fabrication of MBDC.

Hot-press compression molding was attempted to resinify two renewable source-derived linear (1→3)-β-D-glucan polymers, i.e., paramylon or curdlan via the generation of reactive aldehyde groups that...

Nb-Si based ultrahigh-temperature alloys with the composition of Nb-22Ti-15Si-5Cr-3Al (atomic percentage, at. %) were prepared by hot press sintering (HPS) at 1250, 1350, 1400, 1450 and 1500 °C. The effects of HPS temperatures on the microstructure, room temperature fracture toughness, hardness and isothermal oxidation behavior of the alloys were investigated. The results showed that the microstructures of the alloys prepared by HPS at different temperatures were composed of Nbss, βTiss and γ(Nb,X)5Si3 phases. When the HPS temperature was 1450 °C, the microstructure was fine and nearly equiaxed. When the HPS temperature was lower than 1450 °C, the supersaturated Nbss with insufficient diffusion reaction still existed. When the HPS temperature exceeded 1450 °C, the microstructure coarsened obviously. Both the room temperature fracture toughness and Vickers hardness of the alloys prepared by HPS at 1450 °C were the highest. The alloy prepared by HPS at 1450 °C exhibited the lowest mass gain upon oxidation at 1250 °C for 20 h. The oxide film was mainly composed of Nb2O5, TiNb2O7, TiO2 and a small amount of amorphous silicate. The formation mechanism of oxide film is concluded as follows: TiO2 forms by the preferential reaction of βTiss and O in the alloy; after that, a stable oxide film composed of TiO2 and Nb2O5 forms; then, TiNb2O7 is formed by the reaction of TiO2 and Nb2O5.

Both the Excess or under production rate disturbs the business cycle and increase the losses. Balanced business cycle is leads to healthy and ensured customer satisfaction and raise of sales volume. This paper discusses such industrial story in which the problem was excess cost incurred due to fast line delivery due to disturbed flow of products in the manufacturing line. This kind of issues usually carried out in two approaches like production management and production engineering. Based on the scientific analysis the production engineering approach was preferred. The flow process analysis carried out to locate the problem area. The ishikawa diagram plotted to identify the relationship between the factors, root cause analysis and validated the same. The Improved Design in tool with appropriate material is suggested for hot forming operation, fabricated and validated all the way to ensure its compatibility. The trails conducted for both conventional and proposed tools five days and performances measured. The improved performance guaranteed. Further the proposed tool validated with quality on its produced products like surface hardness of product, micro structural investigation on surface and core. The tool diaphragm validated by mechanic testing, cover assembly validation test and cost analysis. Cooling rate reduced 34.78%, cycle time reduction 24.24%, production rate augmented 30.91% per hour. The use of propane gas proposed than LPG to reduce the cost.

Biokomposit adalah material yang telah banyak dimanfaatkan oleh industri otomotif di negara maju terkait dengan peraturan ketat menyangkut isu penghematan energi dan lingkungan karena emisi gas buang serta material yang ramah lingkungan. Limbah alam lignoselulosa memiliki potensi menjadi bahan penguat untuk biokomposit. Telah banyak penelitian yang menggunakan serat atau partikel bahan alam untuk membuat biokomposit polimer bertujuan peningkatan kekuatan, ringan, serta ramah lingkungan. Penelitian ini menggunakan biji buah salak yang biasanya dibuang, dihancurkan menjadi bentuk serbuk dengan ukuran < 100 yang dimanfaatkan sebagai filler penguat untuk biokomposit matriks polipropilena (PP). Dalam penelitian ini digunakan proses hot press dengan campuran biji salak dan PP dari tiga variasi komposisi dan tiga variasi tekanan hot press. Variasi komposisi berupa tiga rasio persentase berat serbuk biji salak /PP, yaitu 20/80, 25/75, dan 30/70 dan diberi variasi tekanan hot press 0,3; 0,35; dan 0,4 MPa. Tebal dan gramasi semua sampel diukur sebelum dilakukan pengujian flexural. Hasil pengujian flexural (ASTM D790-17) menunjukkan bahwa kekuatan flexural meningkat dengan penambahan kandungan filler demikian pula dengan peningkatan tekanan hot press. Kekuatan tertinggi sebesar 45,46 MPa yang didapat dari sampel dengan 30 % berat serbuk biji salak dengan tekanan hot press 0,4 MPa. Kekuatan flexural dan gramasi sampel memiliki nilai lebih baik daripada komposit woordboard yang saat ini digunakan oleh industri otomotif.

By regulating preheating time, effects of water/moisture immigration and distribution in wood on sandwich compression formation were investigated in this study. Kiln-dried poplar wood was first immersed in water to result in high moisture content (MC) layers on wood surfaces. These wood specimens were then conditioned at room temperature in sealed plastic bags and preheated with hot press platens at 180 °C to drive water/moisture into wood. Wood preheated for 10–600 s contained one to two high MC layers all the time. Extended preheating time moved the high MC layers from wood surfaces to the center. Mechanical pressure on preheated wood specimens resulted in sandwich compressed wood with the compressed layer(s) position(s) consistent to that of the high MC layer(s) before compression. The positions of compressed layer(s) and MC peak(s) both increased exponentially as a function of the logarithm of preheating time. Wood preheating by platens led to water/moisture migration and therefore controlled water/moisture distribution, thus promoting the softening of specific wood layer(s), which is mainly responsible for sandwich compression. A logarithmical model that can be used for predicting the position(s) of the compressed layer(s) was developed.

Investigations on ion-transport and materials properties of poly (ethylene oxide) (PEO) based Zn2+ conducting Nano-Composite Polymer Electrolyte (NCPE) membranes: [90 PEO: 10 Zn (CF3SO3)2] + xAl2O3, have been reported. NCPE films have been prepared by a completely dry hot-press cast technique using Solid Polymer Electrolyte (SPE) composition: [90 PEO: 10 Zn (CF3SO3)2] as I phase and Al2O3 nano-filler particles (< 50 nm) as II- Phase dispersoid. In an earlier study, SPE used here as I phase host has been identified as optimum room temperature conducting film exhibiting (srt) ~1.01 x 10-5 S/cm. As a consequence of fractional dispersal of nano-filler particles in SPE, additional srt enhancement of an order of magnitude was obtained. This has been referred as NCPE OCC film. Ion transport behavior in NCPE OCC has been characterized in terms of ionic conductivity (?), total ionic (tion)/cation (t+) transport numbers which have been measured using different ac/dc techniques. Temperature dependent conductivity study has also been carried out to understand the mechanism of ion transport and to compute activation energy (Ea) from ‘log s-1/T’ plot. Materials and thermal properties have been characterized with the help of SEM, XRD, FTIR and DSC / TGA techniques.

The present article focused on the residual strains and deformation of the laminates fabricated by rapid hot press process using prepreg. Strain gauges and laser tracker were utilized to measure th...

Mixtures of refined wheat flour (RWF) with flours from different sources could impact the functional qualities and shelf life of wheat-based products. Storage stability is one of the most critical factors for tortilla quality. Tortillas made from yam (Dioscorea sp.) wheat composite flours were characterized. RWF was substituted with 5%, 10%, 15%, and 20% of fermented yam flour-brown (FYF) and unfermented yam flour-white (UYF). Farinograph water absorptions of UYF-composite flours (65.5% - 77.1%) were significantly (P < 0.05) higher than FYF-composite flour absorptions (60.5% - 61.5%). During storage, moisture contents of composite flour tortillas increased while the RWF-tortilla decreased. Tortilla from FYF-composite flour exhibited greater strength (3.1 N at day zero on average) compared to UYF-composite tortillas (2.1 N at day zero on average), while UYF-composite flour tortillas had good extensibility and rollability properties. The properties and composition type and ratios of flour blends affected tortilla quality during the storage period. The substitution of RWF with 15% or 20% UYF would be more suitable for making tortilla with improved properties compared to that of FYF.

As society considers alternatives to energy systems based on fossil fuel combustion, high-temperature proton exchange membrane (HT-PEM) fuel cells may play an important role in our future energy and transportation portfolio. When compared to low-temperature proton exchange membrane (LT-PEM) fuel cells, HT-PEM technology offers enhanced electrode kinetics, simplified water management, and most notably increased tolerance to fuel impurities such as carbon monoxide. However, compared to more conventional LT-PEM systems, less is known about the durability, performance, and fabrication of HT-PEM materials. Comprised of multiple layers, the membrane electrode assembly (MEA) is a fuel cell’s central component. In a fabrication process similar to LT-PEM MEAs, the proton-conducting membrane, electrodes, gas diffusion layers and sub gaskets are usually hot-pressed together. The parameters surrounding the hot-pressing operation can have a significant impact on the ultimate performance of the fuel cell, in addition to influencing process reliability and repeatability. In the current research, measurements of MEA thickness, impedance, and adhesion strength were obtained for samples over a range of conditions to optimize for the most suitable processing parameters. Testing in this study quantified the effects of hot-press time, temperature and pressure, within ranges of 1-10 minutes, 140 – 200oC, and 7.72 – 92.67 MPa (1120 - 13440 psi), respectively. After hot pressing, the MEA samples were tested for resistance with a 1260a Solartron impedance gain phase analyzer in tandem with a Solartron Ametek 12962a sample holder, and with a Scott internal bond tester for adhesion strength. Based on the results of these tests the optimal hot-press parameters were established, four 25 cm2 MEA were built and tested for performance with post-mortem analysis conducted utilizing scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX). These measurements enabled interrogation of potential sources of conductivity loss associated with material layer delamination and/or dehydration of phosphoric acid in the polybenzimidazole (PBI) membrane. In this case, all tests were conducted at 140oC and the resulting material assembly was allowed to cool to room temperature in a nitrogen glove box prior to executing conductivity measurements (i.e., inverse of resistance). Our results have demonstrated that the optimal conditions for MEA hot-pressing for the HT-PEM system are around 170oC and 23.1 MPa for 5 minutes. Each curve in Figure 1 represents the performance of in-house MEAs, prepared using the optimized hot-pressing condition, with variation of platinum-on-carbon content (Pt/C) and total Pt loading. The data presented in Figure 1 demonstrate the effect of varying electrode thickness on MEA performance. Figure 1

Among refractory metals, tantalum has long been the primary material of use in high strain rate applications. Hot pressing (HP) is a technique to produce specimens with high density and homogeneous...

Peningkatan konsumsi serta permintaan material tekstil membuat produk tekstil dari segi material dan elemen dekoratif berkembang. Perkembangan tersebut dapat dicapai dengan pengaplikasian tekstur pada plastik cling wrap menggunakan teknik hot press secara sederhana dengan setrika. Tujuan dari penelitian ini, yaitu untuk memahami cara menerapkan teknik hot press pada material cling wrap sebagai upaya menghasilkan olahan bertekstur yang kemudian dapat diolah menjadi produk fashion berupa perhiasan. Penelitian Tugas Akhir ini merupakan penelitian kualitatif dengan metode pengumpulan data, yaitu studi literatur, observasi, dan eksplorasi dengan batasan masalah berupa jumlah lembaran, suhu, waktu dan tema. Hasil dari penelitian ini berupa alternatif pengolahan material plastik sebagai upaya menghasilkan produk aksesoris fashion.

The hot-press technique is applied to lower the sintering temperature and shorten the sintering process of Li1.5Al0.5Ge1.5(PO4)3 (LAGP). The hot-press conditions are studied to obtain well sintered LAGP pellet with high Li ion conductivity. The highest Li ion conductivity is obtained at 550 oC for 30 min at 7 MPa and the values are 3.8, 3.4 and 1.8×10-4 S cm-1 in bulk, grain-boundary and total conductivities, respectively. These values are comparable to reported values, however, sintering temperature is more than 250 oC lower and holding time is more than several hours shorter than conventional sintering processes.

Hot-press drying has gained attention due to its excellent drying rate and surface strengthening effect. The moisture state in poplar lumber (Populus tomentosa) with moisture content (MC) above fibre saturation point (FSP) was analyzed during hot-press drying. The effect of heating platens’ temperature on the temperature and pressure inside poplar lumber was investigated. The moisture state changes inside the poplar lumber during hot-press drying were further analysed in accordance with the measured pressure and theoretical pressure calculated with the measured temperature inside poplar lumber. Results were as follow: When the heating platens’ temperature increased from 120 to 140 °C, the maximum values of temperature and pressure also increased by 14.5 and 26.2%, respectively. However, a delay occurred between the maximum values of pressure and temperature. The moisture at the center layer of poplar lumber with MC above FSP was in liquid state, i.e. unsaturated water under overpressure condition in hot-press drying process. Flashing occurred to the unsaturated water in poplar lumber during the opening period of heating platens and resulted in the decrease in MC. This phenomenon is the main moisture transfer mode in wood hot-press drying process with MC above FSP.

Metallic material processing plays a significant role in terms of global environmental impact which contributes to the climate change phenomena that is a serious international environmental concern and the subject of much research and debate. Thus, energy-and resource-efficient strategies in the metal shaping technology domain need to be identified urgently. A frequent theme in the debates that surround waste and resources management is the extent to which the recycling of metallic materials offers genuine benefits to the environment. Solid state recycling techniques allow the manufacture of high density aluminum alloy parts directly from production scrap. In this paper the environmental impacts associated with ‘meltless’ scrap processing routes through hot press forging process with varying parameter has been studied. A comparative analysis has been performed, with different operating temperature and holding time of direct recycling hot press forging process AA6061 aluminum chip. The importance of an environmental performance analysis that included both parameter setting was discussed and highlighted throughout the paper. Finally, the application of the proposed parameter setup has resulted in the setting up of an eco-process. Indeed, LCA study on recycling (solid-state) are recommended as well it gives a noteworthy benefit to the environment and to fill the knowledge gap.