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(Pb0.87Ba0.1La0.02)(Zr0.68Sn0.24Ti0.08)O3 (PBLZST) antiferroelectric (AFE) ceramics have been prepared by hot-press sintering method and conventional solid-state reaction process, and the dependence of microstructure and energy storage properties of the ceramics on sintering approaches has been studied. The results reveal that not only the microstructure, but also the electrical properties of the PBLZST AFE ceramics are significantly improved by using the hot-press sintering method. Samples resulting from the hot-press sintering process have high breakdown strength of 180 kV/cm which results from the increase of density. Coupled with large polarization, the hot-pressed AFE ceramics are shown to have a high recoverable energy density of 3.2 J/cm3. The recoverable energy density of the hot-pressed PBLZST AFE ceramics is 100% greater than the conventional sintered specimens with recoverable energy density of 1.6 J/cm3.

Five different soybean protein sources were added to wheat flour to increase the protein content by 15–25%, and the resulting composite flours were optimally processed into hot-press tortillas in a pilot plant. The rheological properties of composite flours were evaluated with the farinograph, alveograph, and other wheat quality tests. Tortilla-making qualities of the control and soybean-fortified flours were evaluated during dough handling, hot pressing, and baking. The resulting tortillas were tested in terms of yield, physical and chemical parameters, sensory properties, color, and objective and subjective texture. The soybean-fortified tortillas had increased yields because of the higher dough water absorption and enhanced essential amino acid scores. Among the five different soybean proteins, the defatted soybean flour (SBM1) with the lowest fat absorption index and protein dispersibility index (PDI) and the soybean concentrate produced the best fortified tortillas. The protein meals with hi...

Refined wheat flours commercially produced by five different U.S. and Mexican wheat blends intended for tortilla production were tested for quality and then processed into tortillas through the hot-press forming procedure. Tortilla-making qualities of the flour samples were evaluated during dough handling, hot pressing, baking, and the first five days on the shelf at room temperature. The predominant variables that affected the flour tortilla performance were wet gluten content, alveograph W (220–303) and P/L (0.70–0.94) parameters, farinograph water absorption (57%) and stability (10.8–18.7 min), starch damage (5.43–6.71%), and size distribution curves (uniform particle distribution). Flours produced from a blend of Dark Northern Spring (80%) and Mexican Rayon (20%) wheat had the highest water absorption, and tortillas obtained from this blend showed the highest diameter and lowest thickness. The whitest and best textured tortillas were obtained from the flour milled from three hard types of Mex...

β-NaBiO3 is obtained by hot press sintering of ilmenite-type NaBiO3 (Au capsule in cubic anvil cell, 6 GPa, 600 °C, 30 min).

The metastable (at 25 °C) high-temperature phase of BaGe3 (tetragonal CaGe3-type structure, space group I4/mmm, Z = 8, powder XRD) is obtained by hot press sintering of arc melted precursor samples using 1% Ba excess for loss compensation (multi anvil press, 15 GPa, 1300 K).

Ca2PO3N (I) and Sr2PO3N (II) are prepared by hot press sintering of stoichiometric amounts of PON and CaO or SrO (multianvil apparatus, 7 GPa, 1100 °C, 60 min) or by solid state reaction (N2-filled silica tubes, 1100 °C, 2 h or 24 h, resp.).

The wet-laid process with flax (base) and polypropylene (binder) fibers has been used to obtain nonwovens for further processing by hot-press molding. Mechanical characterization of nonwovens has revealed that slight anisotropy is obtained with the wet-laid process as better tensile strength is obtained in the preferential deposition direction. The thermo-bonding process provides good cohesion to nonwovens, which is critical for further handling/shaping by hot-press molding. Flax:PP composites have been processed by stacking eight individual flax:PP nonwoven sheets and applying moderate temperature and pressure. As the amount of binder fiber is relatively low (< 30 wt%) if compared with similar systems processed by extrusion and injection molding, it is possible to obtain eco-friendly composites as the total content on natural fiber (flax) is higher than 70 wt%. Mechanical characterization of hot-pressed flax:PP composites has revealed high dependency of tensile and flexural strength on the total amount of binder fiber as this component is responsible for flax fiber embedment which is a critical parameter to ensure good fibermatrix interaction. Combination of wet-laid techniques with hot-press molding processes is interesting from both technical and environmental points of view as high natural fiber content composites with balanced properties can be obtained. POLYM. COMPOS., 2012. (c) 2011 Society of Plastics Engineers, This work is part of the project IPT-310000-2010-037, "ECOTEXCOMP: Research and development of textile structures useful as reinforcement of composite materials with marked ecological character" funded by the "Ministerio de Ciencia e Innovacion," with an aid of 189540.20 euros, within the "Plan Nacional de InvestigacionCientifica, Desarrollo e InnovacionTecnologica 2008-2011" and funded by the European Union through FEDER funds, Technology Fund 2007-2013, Operational Programme on R+D+i for and on behalf of the companies." It is also acknowledged the project "WET-TEX: Implementacion de la tecnologia wet-laid en el desarrollo de nuevos textiles medico-sanitario" with expedient number IMIDIC/2010/137 (total aid of 284400 euro), and the project "WET-TEX II: Implementacion de la tecnologia wet-laid en la investigacion y desarrollo de paneles para aplicaciones tecnicas a partir de residuos procedentes de la industria textil." with expedient number IMDEEA/2011/167 (total aid of 255000 euro) funded by IMPIVA and cofunded (80%) by the European Union through FEDER funds, Valencian Community Operational 2007-2012.

In this article, the reactivity of Ti2AlC powders, with 3 and 10 μm alumina, Al2O3, fibers during pressure-assisted sintering is explored. Samples were fabricated by hot-isostatic-pressing (HIPed) or hot-pressing (HPed), and characterized by X-ray diffraction, differential thermal analysis, and electron microscopy—both scanning and transmission—equipped with energy dispersive X-ray spectroscopes. Samples prepared at 1300°C were fully dense, with no apparent reaction between fiber and matrix. In samples HPed to 1500°C, even pure Ti2AlC powders dissociated to Ti3AlC2 according to: 2 Ti2AlC = Ti3AlC2 + TiAlx (l) + (1-x) Al (l/v), with x

The carbon fabric composites (CFC) filled with the particulates of graphite, MoS2, and PTFE, respectively, were prepared by dip coating and hot press molding technique. The tribological properties of the resulting composites were investigated systematically on a model ring-on-block test rig under dry sliding conditions. Experimental results showed that the addition of graphite and MoS2 significantly improved the friction and wear behavior, but PTFE as filler was harmful to the improvement of the tribological properties of the CFC. Tribological tests also revealed that the CFC showed better tribological properties under higher load and exhibited worse tribological properties under higher sliding speed. Moreover, it also can be concluded that the transfer film formed on the counterpart surface during the friction process largely accounted for the friction and wear behavior of CFC. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Effect of temperature on hygroscopic thickness swelling rate of lignocellolusic fillers/HDPE (high density polyethylene) composites was investigated. The composites were manufactured using a dry blend/hot press method. In this method, powder of plastic and dried powder of lignocellolusic material were mixed in high-speed mixer and then the mixed powder were pressed at 190°C. Lignocellolusic fillers/HDPE composites panels were made from virgin and recycled HDPE (as plastic) and wood sawdust and flour of rice hull (as filler) at 60% by weight filler loadings. Nominal density and dimensions of the panels were 1 g/cm3 and 35 × 35 × 1 cm3, respectively. Thickness swelling rate of manufactured wood plastic composites (WPCs) were evaluated by immersing them in water at 20, 40, and 60°C for reaching a certain value where no more thickness was swelled. A swelling model developed by Shi and Gardner [Compos. A, 37, 1276 (2006)] was used to study the thickness swelling process of WPCs, from which the parameter, swelling rate parameter, can be used to quantify the swelling rate. The results indicated that temperature has a significant effect on the swelling rate. The swelling rate increased as the temperature increased. The swelling model provided a good predictor of the hygroscopic swelling process of WPCs immersed in water at various temperatures. From the activation energy values calculated from the Arrhenius plots, the temperature had less effect on the thickness swelling rate for the composites including wood sawdust compared with the rice hull as filler and the composites including recycled compared with the virgin HDPE as plastic. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers

AgInS2 crystal could be grown by a Hot-Press (HP) method with pressure (10 ∼ 90 MPa) at 700 °C. From X-ray diffraction measurements, the samples grown at 10 ∼ 40 MPa were found to contain only AgInS2 phase. However, a signal from AgIn5S8 phase increased with increasing pressure above 40 MPa. The lattice parameters of a and c axes increased and were almost constants with increasing pressure below and above 40 MPa, respectively. A donor-type defect of interstitial Ag might be enhanced to electrical conductivity in the all samples because samples indicated n-type conductivity examined by thermoprobe analysis. Moreover, high purity sample could be obtained in the HP method because a free exciton emission was clearly and no deep emission was observed in the photoluminescence spectrum. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Undoped polycrystalline AgGaSe2 crystals were successfully grown at a low temperature (700 °C) using a hot-press method. The sizes of the samples were 2 cm in diameter. The grain size was approximately 55 nm. The presence of lattice defects such as Se vacancies and/or Ag interstitials may lead to an enhancement in electrical conductivity. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A dense TiS3 sample is prepared by solid state reaction of a 1:4 mixture of Ti and S (evacuated quartz ampoule, 600 °C) followed by spark plasma sintering in vacuum and subsequent hot press molding (600 °C, 50 MPa, 10 min).

A new, thermally curable, aqueous acrylic resin is introduced as duroplastic binder for automotive trim parts. This one-component resin has good storage stability and crosslinks upon heating to 180–220°C. Wood fibers are impregnated with the resin using the blow-line technique and can be further processed to fiber mats. With other natural fibers like flax, hemp or sisal, preformed mats are impregnated with the acrylic resin solution. Both methods give prebound fiber mats with good storage stability and thermoplastic deformability. During a final hot press step, the desired shapes are formed and the resin is crosslinked. Composite parts bound with the new acrylic resin show high stiffness and strength and meet the ecological requirements of the automotive industry.

Bismaleimdes (BMI) and experimental polyimides were resin transfer molded into carbon fiber fabrics using a custom-built injection mold placed within a vacuum hot press. This represents the first time that the latter type of materials has been resin transfer molded. This is a critical stage in developing materials and processing methods for future aerospace applications, such as the High Speed Civil Transport (HSCT).

The behaviour of wood with the heat-compressed treatment method was evaluated. Fire retardance and endurance of wood treated with basic nitrogen compounds and phosphoric acid were much improved by the compressed method using a hot press. In this way, the concentration of chemical contents and the density of wood were raised at the surface of the treated wood and it increased the specific gravity of the treated wood as a whole. It was recognized that the increase of specific gravity improved fire retardance and endurance, and fire endurance of wood was indicated by the equation of addition of chemicals and specific gravity. It is more effective to increase the specific gravity of wood at the surface to improve fire endurance. Wood treated with chemicals showed a high limiting oxygen index in proportion to the increase in the addition of chemicals regardless of the treatment method, and high fire endurance was not always accompanied by a high limiting oxygen index.