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The inner part of gewang (Corypha utan Lam.) trunk has significantly lower physical-mechanical properties as well as biodeterioration resistance, compared to outer parts. This study investigated a method for improving the physical-mechanical properties and biodeterioration resistance of glued laminated lumber made from the inner part of gewang trunk (GLIT). The effects of pretreating the lamina with densification and exposing the GLIT to smoking process were investigated. The seven layers of GLIT samples were bonded with isocyanate adhesive at a glue spread of 280 g/m2, then smoked for 15 days. Solid lumber pieces made from the inner part as well as the outer part of GLIT were also prepared for comparative purposes. Physical and mechanical properties of the lumber samples were tested according to Japanese agricultural standards. Meanwhile, dry-wood termite and wood decaying fungi resistances of the lumber samples were determined according to Indonesian standard. Results showed that overall physical-mechanical properties as well as dry-wood termite and decay resistances of densified-smoked GLIT were enhanced significantly. Pretreating of lamina and post-production smoking can be considered as a potential method to improve physical-mechanical properties and biodeterioration resistance of the GLIT.

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...

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.

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...

The bending angle at the peak load is regarded as the most important parameter for evaluating bending properties of hot-press-forming (HPF) steels. However, it is not a mechanics-based parameter for the bending criterion, and the data interpretation is difficult because bending criteria in relation with microstructures and associated bending mechanisms have not been verified yet. In this study, effects of coating and baking treatments on bending angles at the peak load of three kinds of 1470 MPa-grade HPF steels were investigated by interrupted three-point bending tests coupled with direct microstructural observation. According to direct observations of sequential cracking processes of V-shaped crack (V-crack), bending procedures were classified into four stages: (1) formation of small V-crack, (2) increase in number and size of V-cracks, (3) initiation of shear-crack propagation from the V-crack tip, and (4) further propagation and opening of the shear crack. The minimum bending angle required for initiating the shear-crack propagation from the V-crack tip was defined as a critical angle, which meant the boundary between the 2nd and 3rd stages. The present bending behavior related with critical bending angle and V-cracking could be interpreted similarly by the fracture-mechanics concept, i.e., the initiation of shear-crack propagation.

We describe the phase stability and suppressed → phase transformation in SiC/SiC fiber-reinforced composites prepared by spark plasma sintering (SPS), resulting in samples of >96% relative density and uniform -SiC microstructure. These samples are compared to ones produced by a hot pressing (HP) technique that results in samples with ~80% conversion to α-SiC hexagonal phases (4H and 6H). The phase transformation in the samples manufactured by SPS is shown to be significantly retarded due to the influence of lower sintering temperature, shorter processing time, and higher pressure. In addition, these samples exhibited hardness values in the range of 22 to 26 GPa, which were higher than those produced by HP, due to the higher density of the SPS samples, as well as relevant differences in phase composition. It was demonstrated that the → phase transformation is independent of fiber content in the composites. This study is of special interest for the production of SiC/SiC composite structures for electronic and structural applications.

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 ...

Kebutuhan papan saat ini terus mengalami peningkatan oleh karena itu penelitian ini dilakukukan dengan memanfaatkan limbah PVC dan limbah cangkang kupang merah sebagai bahan baku pembuatan papan komposit sehingga dapat menaikan nilai dari limbah PVC dan limbah cangkang kupang merah.Tujuan dari penelitian ini untuk mengetahui pengaruh ukuran filer dan perbandingan komposisi cangkang kupang merah dengan PVC terhadap sifat fisis dan mekanis papan komposit. Pembuatan papan komposit ini dilakukkan dengan cara mencampurkan serbuk cangkang kupang dengan PVC kemudian perlakuan yang diberikan dengan melakukan variasi ukuran cangkang kupang 20, 30,40,50,dan60 mesh dan perbandingan komposisi antara PVC dengan cangkang kupang yaitu 30%:70%, 40%:60%, 50%:50%, 60%:40%, 70%:30% kemudian dicetak dan dilakukan pengempaan dengan suhu 120oC menggunakan hot press selama 60 menit. Sehingga dari penelitian diperoleh hasil kerapatan terbaik pada kondisi 60 mesh dan perbandingan komposisi 30%:70% dimana nilai densitas atau kerapatan 1,234gr/cm3, sedangkan untuk kadar air,pengembangan tebal, dan kuat patah didapat hasil terbaik pada kondisi 60 mesh dengan perbandingan komposisi 70%:30% dimana persentase kadar air 0,3108%, presentase pengembangan tebal 0,138% , nilai kuat patah (modulus of repture) 1092,57 Kgf.

Al−high Si alloys were designed by the addition of Cu or Mg alloying elements to improve the mechanical properties. It is found that the addition of 1 wt.% Cu or 1 wt.% Mg as strengthening elements significantly improves the tensile strength by 27.2% and 24.5%, respectively. This phenomenon is attributed to the formation of uniformly dispersed fine particles (Al2Cu and Mg2Si secondary phases) in the Al matrix during hot press sintering of the rapidly solidified (gas atomization) powder. The thermal conductivity of the Al−50Si alloys is reduced with the addition of Cu or Mg, by only 7.3% and 6.8%, respectively. Therefore, the strength of the Al−50Si alloys is enhanced while maintaining their excellent thermo-physical properties by adding 1% Cu(Mg).

Commercial ceria?gadolinia powders were used to prepare dense CGO (5 mol% Gd) samples, by hot press method at relatively low temperature (1000?C). To study the effect of post-sintering, further the as-sintered bodies were subjected into different thermal treatments 1100oC-1400oC. The sintered samples were characterized by impedance spectroscopy as a function of temperature in air, in order to identify each microstructural contribution to the overall electrical behaviour. Scanning electron microscopy shows that the increase in the temperature of thermal treatment leads to grain growth. Electrical properties were studied with different oxygen partial pressuresand ion blocking methods. Y2O3 (5 wt%) additions were used to seek the grain boundaries heterogeneities effectsin CGO material, prepared by hot press and subjected into post sintering thermal treatments. Electrical conductivities of CGO samples were analysed with and without Y2O3 additions. 6D12-6554-B318 | Jo?o Carlos Castro Abrantes info:eu-repo/semantics/acceptedVersion

Grain boundaries are frequently responsible for a poor performance of gadolinium-doped ceria-based electrolytes, due to a low ionic conductivity, orders of magnitude smaller than the bulk conductivity. Silica, the dominant impurity in many low-grade ceramics, namely, in ceria-based materials, has a detrimental effect on grain boundaries conductivity. Several previous works had explored the silica-scavenging effect. In the present work, we exploit an alternative approach using the addition of 5% (w/w) of Y2O3, as silica scavenging agent, and sintering by hot pressing at low temperature to minimize bulk dissolution of yttrium in the CGO lattice. Gadolinium-doped ceria-based powders were co-fired with additions of 1% (w/w) of silica, and silica and yttrium oxide to test the silica scavenging role of yttrium. The samples were prepared by hot press at low temperature (1000?C) and were characterized by impedance spectroscopy as a function of temperature in air, in order to de-convolute different microstructural contributions to the overall electrical behaviour. Combined information obtained from structural, microstructural, and electrical characterization allowed one to study the impact of new phases on the resulting ceria-based solid electrolytes. 6D12-6554-B318 | Jo?o Carlos Castro Abrantes info:eu-repo/semantics/publishedVersion

This work investigated the feasibility of using western juniper (Juniperus occidentalis) as a material to manufacture oriented strandboard (OSB) panels. Four different material combinations of juniper sapwood, heartwood, and fibrous bark were compared with regular southern yellow pine (Pinus sp.) strands. The OSB panels were made at an oven-dry density of 560 kg/m3. One pine control panel was also made at a higher density of 650 kg/m3 with a 5% addition of phenol formaldehyde (PF) resin and a 0.5% addition of wax. The single-layer panels were formed with a hot press, and the physical and mechanical properties were tested according to the ASTM standard D1037 (2020). The testing indicated that western juniper is a potential material for manufacturing of OSB panels. The properties of the juniper panels were equivalent or slightly better than those of the southern yellow pine panels at the same density level, except for the modulus of elasticity (MOE). The lower density of the juniper OSB panels may have benefits in construction applications and can decrease transportation costs.

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.

The compression properties, wear resistance and electrical conductivities of TiCx/Cu composites fabricated via thermal explosion reaction combined with hot press in Cu–Ti-CNTs system at various nano-sized TiCx content with similar size were investigated. Results show that nano-sized TiCx can be effectively enhanced the Cu matrix. The σUCS, σ0.2 and wear resistance increased with the increasing content of TiCx particles. The ef and electrical conductivities decreased with increase of TiCx content. The ultimate compressive strength (σUCS), yield strength (σ0.2), Brinell Hardness and wear resistance increase with sacrificing the ef and the electrical conductivities. The 30 vol.% TiCx/Cu composites possess the highest σUCS, σ0.2, Brinell Hardness, wear resistance and the lowest ef, electrical conductivities among the 25–30 vol.% TiCx/Cu.

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.

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.

espanolEsta investigacion tuvo por objetivo evaluar el efecto de la adicion de harinas de amaranto, quinoa y avena en la reologia, composicion quimica, digestibilidad “in vitro” y propiedades fisicas de tortillas de harina producidas por prensado en caliente. El parametro C1 de Mixolab (estabilidad de la masa) incrementa 33% con la adicion de amaranto. Se observa que la fibra soluble y la proteina en las tortillas con la adicion de harinas se incrementa 31.4% y 27.1%, respectivamente. Las tortillas del tratamiento 5:5:20 avena:quinoa:amaranto requiere la misma fuerza para deformacion y ruptura al dia 6 y menor L (16.1%) y mayor a* (27.4%) y b* (23.1%) en relacion al control. La aceptacion sensorial fue la misma en terminos de textura pero menor en terminos de olor para la tortilla del tratamiento 5:5:20 avena:quinoa:amaranto. La sustitucion parcial de la harina de trigo por harina de amaranto, quinoa y avena tiene efecto positivo en contenido de proteina, fibra dietaria total y digestibilidad “in vitro” de proteina de las tortillas. EnglishThe aim of this research was to evaluate the effect of the popped amaranth flour on the rheology, chemical composition, protein digestibility and physical properties of hot-press tortillas elaborated with a wheat, oat and quinoa flour, compared with refined wheat flour. Mixolab C1 (dough stability) increased 33% with amaranth addition. Results showed that tortillas containing 5:5:20 oat:quinoa:amaranth increased 31.4% and 27.1% soluble dietary fiber and protein than control, respectively. Protein “in vitro” digestibility increased 1.02% and crude fat reduced 35.6%. Tortilla treatment 5:5:20 required same force to deform and to rupture at day 6, and showed a lower L* (16.1%) and higher a*(27.4) and b* (23.1%) than control. Texture acceptance was the same, and odor acceptance was lower for tortilla treatment 5:5:20, compared to control. The partial replacement of wheat flour with amaranth:quinoa:oat flour positively influences the protein content, total dietary fiber content and protein digestibility of tortillas.

Hot press formed parts in a fully martensitic structure limit its application in the centre pillar, which requires high collision resistance. In this study, the combined effect of the patchwork and...

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.

Films formed from cellulose nanofibrils (CNFs) are known to be good barrier materials against oxygen, but they lose this feature once placed in humid conditions. To tackle this issue, we applied an optimized pressing condition under elevated temperature to increase the films&rsquo, density and improve their barrier performance. Furthermore, a water barrier coating was employed on the surfaces to control the moisture uptake at high relative humidity (RH). Neat self-standing films of CNF with the basis weight of 70 g/m2 were made through a filtration technique and pressed for 1 hour at 130 &deg, C. The resulting nanostructures were covered on both sides using a water-borne barrier layer. Hot-pressing resulted in a significant reduction in oxygen transmission rate (OTR) values, from 516.7 to 3.6 (cm3/(m2&middot, day)) and to some degree, helped preserve the reduced oxygen transmission at high relative humidity. Introducing 35 g/m2 of latex coating layer on both sides limited the films&rsquo, swelling at 90% RH for about 4 h and maintained the OTR at the same level. A finite element model was used to predict the dynamic uptake of water into the systems. The model was found to over-predict the rate of water uptake for uncoated samples but gave the correct order of magnitude results for samples that were coated. The obtained data confirmed the positive effect of hot-pressing combined with coating to produce a film with low oxygen transmission rate and potential to maintain its oxygen barrier feature at high relative humidity.

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.

Owing to the large contact surface area in geometry, disc-shaped polymer particles and their fascinating properties compared to those of spherical particles have received increasing attention. Alth...

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...

An in situ hot press bonding technology has been developed to clad aluminium on magnesium. Followed by regular hot rolling, magnesium sheets, covered by ductile and corrosion-resistant aluminium wi...

The purpose of this study was to investigate a method for improving the physical and mechanical properties of laminated board made from oil palm trunk (OPT). The effects of pretreating the lamina with heat-pressure and altering the lamina composition of the laminated board were investigated. The outer third of OPT in cross-section had high-density wood, while the underlying third had low to medium density. The hot press was applied to pretreat the lamina that had low to medium density. The lamina were 1.5 cm in thickness, 5 cm in width, and 65 cm in length. The hot press was applied at 2.94 MPa or 4.41 MPa at 150 ℃ for 60 minutes, and the target thickness of the lamina was 1 cm. The three layers of the laminated board samples were bonded with isocyanate adhesive at a glue spread of 300 g/㎡ and cold pressed at 0.98 MPa for 3 h. The laminated board samples were tested according to Japanese Agricultural Standard (JAS) 234-2003. The results showed that the densification of the inner lamina did not significantly affect the physical-mechanical properties of the laminated board produced. However, the laminated board made with high-density laminas for the outer layers fulfilled the JAS 234-2003 standard for the modulus of elasticity and the modulus of rupture.

A Nanofiltração com Solventes Orgânicos OSN, é uma das tecnologias de maior interesse, em pro-cessos de separação, de um ponto de vista sustentável, quando comparada com processos como a des-tilação e a evaporação. A maioria das investigações relacionadas com esta tecnologia, estão direciona-das para a estabilidade química de membranas poliméricas, estabilidade essa que é obtida através de técnicas, que utilizam reagentes tóxicos, e alguns químicos que podem causar um enorme desperdício orgânico, durante o processo de fabricação destas membranas. É, por isso, controverso afirmar, que a Nanofiltração com Solventes Orgânicos OSN é uma tecnologia desenhada para resolver problemas re-lacionados com a sustentabilidade, uma vez que a própria fabricação de membranas através desta tec-nologia, está longe de ser sustentável. Para melhorar a sustentabilidade desta tecnologia, foi investigado e desenvolvido, durante a fabri-cação de membranas PEEK, um novo método de secagem, mais eficiente que os convencionais méto-dos, tornando o processo de secagem mais rápido, e com um consumo energético menor. Foram ainda investigados, durante o passo de troca de solvente, diversos solventes, de forma a encontrar um solvente economicamente acessível e menos tóxico, capaz de otimizar o desempenho da membrana, e tornar o processo mais verde. A metodologia usada neste estudo baseou-se na comparação de membranas PEEK, que foram sujei-tas a diferentes temperaturas (30ºC, 50 ºC, 80 ºC, 100 ºC, 120 ºC, 140 ºC, 160 ºC), diferentes pressões (10, 30, 50, 100 bar), e tempo de 15 segundos, através de uma prensa quente. Foi feita ainda a compa-ração entre dois equipamentos de secagem diferentes (O Forno Convencional e a Prensa Quente). Por fim, foi investigado o efeito de dois solventes (Água Desionizada e Acetona), na etapa de troca de solvente. Os resultados mostraram que, ao aplicar pressão e aumentar a temperatura, ao mesmo tempo, o limite de peso molecular MWCO tendeu a diminuir, criando membranas mais apertadas. Essa diminuição foi mais pronunciada, usando a água desionizada como solvente. Foi possível obter membranas mais uni-formes, uma vez que a prensa quente, é constituída por 2 placas de metal que aplicam o calor direta-mente na membrana e portanto, tem a capacidade de (após serem aquecidas à mesma temperatura), distribuírem o calor uniformemente pela membrana. Por meio desse método, foi ainda possível reduzir o tempo de secagem, de 1 hora, para 15 segundos, diminuindo o consumo energético. De uma forma geral, foi possível tornar a Nanofiltração com Solventes Orgânicos OSN, uma tecnologia mais susten-tável. Organic Solvent Nanofiltration OSN, is considered as one of the most attractive technologies in membrane separation processes, mainly, due to its reputation as sustainable process, comparing with distillation or evaporation processes. Curiously, the main research made in OSN, is dedicated on im-proving chemical stability of polymeric membranes, and this chemical stability is obtained by several techniques (during membrane fabrication process), which use toxic reagents, and some chemicals can cause huge amounts of organic waste as well. So ironically, although OSN technology being designed to overcome problems related to sustainability, the fabrication of OSN membranes, is far from being sustainable. In order to improve the sustainability of this technology, it was investigated and developed, during the fabrication of OSN membranes, a new drying method, applied to PEEK membranes, more efficient than conventional drying methods, and capable of making the drying process faster, with less energy consumption. It was Investigated, as well, during the solvent exchange step, a cheaper and less pollutant solvent, capable of, making the process greener, and optimizing the membrane performance. The methodology used in this study was based on the comparison of PEEK membranes dried at different temperatures (30ºC, 50 ºC, 80 ºC, 100 ºC,120 ºC,140 ºC,160 ºC) pressures (10, 30, 50, 100 bar), and time of 15s, using a Hot Press Machine. It was made the comparison as well between two different drying equipment (Conventional Oven and Hot Press Machine), and finally it was investigated the effect of two different solvents (Deionized water and Acetone) in the solvent exchange step. The results showed that, by applying pressure and increasing the temperature, at the same time, the MWCO tended to decrease, creating tighter membranes. This decrease was more pronounced, in mem-branes previously immersed in deionized water. Also, more uniform membranes were achieved, as the hot press equipment, applied the heat directly into the membrane, through their heated metal plates, that distributed heat evenly across the membrane. Through this method, it was possible to decrease the dry-ing time during the drying process, from 1 hour to 15 seconds, decreasing the energy consumption. It was possible to make the Organic Solvent Nanofiltration OSN a more sustainable technology.