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21.
Ageing behavior of acrylic polyurethane varnish coating in artificial weathering environments 总被引:2,自引:0,他引:2
Polyurethane-based coatings reinforced by ZnO nanoparticles (about 27 nm) were prepared via solution blending. The ZnO/PU films and coats were fabricated by a simple method of solution casting and evaporation. The mechanical properties of the films were investigated by a universal material test, and the abrasion resistance of the prepared coats was evaluated by a pencil-abrasion-resistance tester. It was found that significant improvement of the PU films in Young’s modulus and tensile strength was achieved by incorporating ZnO nanoparticles up to 2.0 wt%, and that the abrasion resistance of the PU coats was greatly enhanced due to the addition of ZnO nanoparticles. Moreover, the antibacterial property test was carried out via the agar dilution method and the result indicated that PU films doped with ZnO nanoparticles showed excellent antibacterial activity, especially for Escherichia coli. 相似文献
22.
The abrasion resistances of CO2 corrosion scales formed on API P110 grade carbon steel at different temperatures and CO2 corrosion behaviour of P110 carbon steel have been investigated utilising weight loss method, scanning electron microscope (SEM) and X-ray diffraction (XRD). The results showed that as the film forming temperature increased, the abrasion rate of CO2 corrosion scales increased firstly and then decreased, the variation trend was similar to that of the corrosion rate, and the maximal abrasion rate was present at 70°C rather than 100°C, at which the maximal corrosion rate was obtained and CO2 corrosion scales were loose and porous and were composed of FeCO3, Fe3C and CaCO3. The abrasion resistances of CO2 corrosion scales formed at 100°C was reinforced by the sand particles embedded easily in the loose and porous layer, together with a very hard residual skeleton, Fe3C. In addition, CaCO3 was worn out easily and substituted by SiO2 during abrasive wear. 相似文献
23.
This study relates to the development of ultraviolet (UV)-curable, organic–inorganic nanocomposite hard coatings for plastic lens substrates, especially for polythiourethane (PTU) and polycarbonate (PC). Novel difunctional thiourethane methacrylate (mercaptoethylsulfide-thiourethane methacrylate: coded MES-TUMA and isophorone diisocyanate-mercaptoethylsulfide-thiourethane methacrylate: coded IPDI-MES-TUMA) was synthesized to enhance the adhesive strength for PTU. On the basis of IR, 1H NMR, electron spray ionisation-mass spectrometry (ESI-MS) analysis and gel permeation chromatography (GPC), the expected structures were confirmed. These difunctional thiourethane methacrylates were easily mixed with multifunctional urethane acrylate, surface-modified ZrO2–TiO2 nanoparticles and photoinitiator in coating formulations. The UV-cured organic–inorganic nanocomposites were very useful as hard coatings for high refractive index plastic lenses such as PTU and PC. 相似文献
24.
冲击参数对氧化铝基耐火材料常温耐磨性的影响 总被引:2,自引:2,他引:2
参照GB/T18301《耐火材料常温耐磨性试验方法》,分别以标准碳化硅砂(36#)、电熔白刚玉砂(36#)和石油支撑剂用陶粒为磨损介质,采用不同压力(300kPa、448kPa和600kPa)的压缩空气和不同量(1kg、2kg)的磨损介质对普通高铝砖(LZ-65和LZ-75)、高炉用高铝砖、磷酸盐结合高铝砖、高纯刚玉砖、刚玉莫来石砖、铬刚玉砖、赛隆结合刚玉砖、微孔刚玉砖和塑性相复合刚玉砖等10种氧化铝基耐火材料进行了磨损实验。结果表明:(1)随着冲击气体压力的增大,10种材料的磨损量都增加,但由于这些材料在组成和结构上的差异,其磨损量增加的幅度存在明显差异。(2)由于磨损介质的颗粒形状和体积密度不同,在相同的冲击气体压力下,磨损介质的流动速度不同,对材料的磨损量也不同,其中,采用碳化硅时磨损量最大,采用白刚玉时次之,采用陶粒时最小。(3)当磨损介质碳化硅砂用量增加1倍时,材料的磨损量增加,但不同材料的磨损量增加幅度不同,其中微孔刚玉砖和磷酸盐结合高铝砖分别增加了1.84倍和1.26倍,而高纯刚玉砖和高炉用高铝砖增加的不足0.4倍。(4)耐火材料的常温耐磨性能取决于其强度和结构的致密性,强度和致密度较高的材料耐磨性能较好。 相似文献
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26.
M. J. Zhan F. C. Wang J. W. Lang W. Z. Shi 《Tribology - Materials, Surfaces & Interfaces》2015,9(3):137-143
WC-Fe composite coatings were prepared on IC45/080A47 steel substrates by argon arc cladding technique. Minute amounts of La were added into the coating, and the microstructure was investigated to find the relation to rare earth. Results show that RE does not change the categories of phases, and the main components remain α-Fe, Fe3W3C, WC and W2C. However, the distribution of carbide particles is optimised. It reduces the agglomeration and bridging in the cladding layer's structure, makes the particles distribute homogeneously and restrains the dissolution of WC and the formation of fishbone shaped dendritic carbides. It promotes the formation of granular carbide and refines grains. It also reserves the WC particles in the composite coating and improves the average hardness and wear resistance. 相似文献
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大型球磨机衬板材料的研究和应用 总被引:8,自引:0,他引:8
研究成功了一种适合于制造大型球磨机衬板的新材料.在不含钼、镍等贵重合金元素前提下,设计的中碳钢以硅、锰、铬为主要合金元素,并加入少量钛、钙、硼、钇、钾、钠等元素,改善钢的组织和淬透性.新材料具有足够的淬透性和淬硬性,经油冷淬火和中温回火处理后,硬度大于55 HRC,冲击韧性大于25 J/cm2,断裂韧性大于40 MPa·m1/2.用于制造大型球磨机衬板,耐磨性比高锰钢衬板提高1倍以上,生产成本降低15%,具有很好的经济效益. 相似文献
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