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The frictional properties between the continuous hot pressing machine board, steel strip, steel strip, and hot press plate, as well as steel strip and sealing strip, were investigated in this paper. Friction coefficient tests were conducted using a friction coefficient tester to determine the friction coefficients between wood materials and polyethylene plastic, steel strip, polytetrafluoroethylene, polyethylene engineering plastic, and steel strip. Factors influencing the friction coefficients of various friction pairs were analyzed with the aim of providing reference for the design and manufacturing of the continuous hot press for laminating artificial boards with pressure air-float veneers. The experimental results indicated that the static friction coefficient between polytetrafluoroethylene and steel at room temperature was 0.10, and the dynamic friction coefficient was 0.01. The static friction coefficient between polytetrafluoroethylene plate and steel plate decreased initially and then increased with the increasing of temperature, while the dynamic friction coefficient continued to increase. In the direction perpendicular to the wood grain, the static friction coefficient was maximum when moving along the polyethylene plastic film, with the value of 0.62. In the friction pair of artificial board and polyethylene plastic, the static friction coefficient of mediumdensity fiberboard ranged between 0.61 and 0.69, while that of particleboard ranged between 0.56 and 0.71. [ABSTRACT FROM AUTHOR]

Sealing materials have a wide range of applications in the fields of mechanical power and petrochemicals, they are important basic components for preventing leaks and maintaining the normal operation of equipment. Graphene micronano sheets have become one of the key sealing materials due to their excellent thermal conductivity, corrosion resistance, and mechanical properties. This article mainly uses graphene micro-nano sheets as the main filler, phenolic resin (PF) and polyvinyl butyral (PVB) as binders, combined with tape casting and hot pressing technology, to study the effects of graphene micro-nano sheets content, binder ratio, and hot pressing pressure on the tensile strength, compression rate, and rebound rate of composite sealing gaskets, and explore the hot pressing and laminated object manufacturing process of graphene micro-nano sheets composite sealing gaskets. The results show that when the content of graphene micro-nano sheets is 55%, the PF/PVB mass ratio is 8:15, the molding pressure is 15 MPa, the molding temperature is 120 °C, and the insulation time is 30 min, the graphene micro-nano sheets composite sealing gasket has the best molding processability and property, which can be prepared to meet the quality requirements of graphene micro-nano sheets composite sealing gaskets. [ABSTRACT FROM AUTHOR]

Preparation process of aramid 1414 armour material and its tensile strength were discussed. Polyamide aramid 1414 bidirectional covered yarn was used as raw materials to prepare plain fabrics. Hot press formation process was adopted to prepare aramid 1414 armour material. Influence rule of formation process and gel content on tensile properties of aramid 1414 armour materials were mainly studied. Through orthogonal test, optimized hot press pross was obtained. When gel content was within 34%~45%, tensile strength and modulus of aramid 1414 armour material were both decreased as increase of gel content. When gel content was the same, weft tensile strength and modulus of aramid 1414 armour material were both better than those in warp. It is considered that warp and weft damage mode are mainly yarn broken and resin crazed when aramid 1414 armour material was under tensile load. [ABSTRACT FROM AUTHOR]

A multi-refractory gold deposit coated with carbon high arsenic sulfide was studied by hot pressing oxidation and cyanidation. The results indicate that the gold leaching recovery of the whole sulfide flotation concentrate is only 76.2% by conventional hot pressurized oxidation-cyanidation process, and the measurements such as decarbonization of hot pressurized oxidation solid product, raw ores pre-carbonization and segmentation flotation of sulfide and arsenic, are all difficult to improve the gold recovery. The effect of organic carbon can be completely eliminated by medium temperature roasting and then cyaniding, the gold leaching rate reaches 94. 7%, and the harmful component arsenic hardly enters the gas phase during roasting. The toxic leaching results of the mixture of roasting-cyanidation slag and neutralization slag of hot press oxidation eutralization slag can meet the general requirements of solid waste. [ABSTRACT FROM AUTHOR]

A new type of composite ceramic tool material was developed with C3N4 as matrix, Ti (C, N) as additive phase and Mo, Ni, Co as metal phase. By hot press sintering, C3N4 based ceramic tool materials were sintered. The fracture toughness, flexural strength and vickers hardness of the composites were meas-ured and the microstructure was analyzed. The results show that the C3N4 based ceramic tool material containing 35% Ti (C, N) and 8% Ni-Co, which was sintered under the sintering temperature of 1600 °C, duration time of 45 min and sintering pressure of 32 MPa, have the optimum mechanics properties. The appropriate content of Ti (C, N) may refine crystal grains of C3N4, increase sintering density, and improve mechanics properties. The microstructure may be fine and uniform with appropriate Ni-Co contents. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Taking Chinese fir wood from plantation as the research object, three technological parameters including hot-pressing temperature (160, 180, 200 °C), hot-pressing time (20, 30, 40 min) and compression ratio (30%, 40%, 50%) were selected, and the compression densification modification test of Chinese fir was carried out by using the full factor experimental design. Based on the mechanical properties, microscopic morphology and crystallinity of wood, the effects of different processing parameters on wood properties were analyzed, and the densification process parameters of Chinese fir wood were optimized. The results showed that the properties of the densified wood prepared by Chinese fir were better under the technological conditions of hot pressing temperature of 180 °C, compression ratio of 50%, and pressing time of 40 min. The flexural strength, flexural modulus of elasticity, tensile strength, and hardness of the densified Chinese fir were 130.4 MPa, 12 338 MPa, 113.1 MPa and 1 631 N respectively, which increased by 112%, 113%, 44%, and 55% compared to the untreated wood. The scanning electron microscope observation showed that almost all the early wood cells were crushed, and there were regular folds along the direction of the wood ray, while some of the late wood cells were crushed, and most of them kept the original cavity structure. The hardness and elastic modulus of the cell wall of the densified wood were 16.7% and 45.7% higher than that of the untreated wood. The crystallinity of wood after compression treatment increased. The crystallinity of cellulose in the untreated wood and compressed Chinese fir was 46% and 53%, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Xi'an Polytechnic University is the property of Editorial Department of Journal of Xi'an Polytechnic University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ni/Al multilayered energetic structural composites with micron scale were prepared by electroless plating followed by hot press process. The effects of original layer thickness ratio on the microstructure, exothermic properties and mechanical properties of the fabricated composites were investigated, and then the fracture mechanism was analyzed. The results show that the interface bonding of Ni/Al multilayered energetic structural composites is perfect and the initial temperature of interface reaction increases with the increase of original layer thickness ratios. The 2/3 Ni/Al multilayered energetic structural composite not only has the highest reaction energy density of 1051.62 J/g, but also has good strength and plasticity. The tensile strength, elongation and bending strength reach 285.05 MPa, 8.87% and 309.09 MPa respectively. When the layer thickness ratio increases from 1/2 to 1/1, both the tensile strength and bending strength increase, the plasticity decreases. This is related to the composition and interfacial structure. Failure mode of Ni/Al multilayered energetic structural composite is delamination mixed with fracture, and the interface delamination gets more serious with the increase of the layer thickness ratio.

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)