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H. Marchebois S. Touzain S. Joiret J. Bernard C. Savall 《Progress in Organic Coatings》2002,45(4):415-421
The effect of addition of conductive pigments like carbon blacks on the corrosion behavior of zinc-rich powder paints coated steel in artificial sea water was investigated. Open circuit potential measurements were used to characterize the cathodic protection ability and duration. Micro-Raman spectroscopy analysis was performed in order to identify the corrosion products and to follow the penetration of the solution inside the coatings.
Two different effects were pointed out: an increase of the porosity induced by carbon addition and a galvanic action between zinc and carbon pigments. The performance of the powder coatings, strongly improved if the carbon amount is sufficient, was compared to the one reported for solvent-based zinc-rich paints. 相似文献
43.
Xiao Tang Min Gao Haosu Luo Jiefang Li Dwight D. Viehland 《Journal of the American Ceramic Society》2020,103(6):3726-3731
Epitaxial CoFe2O4 (CFO) and SrRuO3 (SRO) nanopillar heterostructures were deposited on Pb(Mg1/3Nb2/3)0.70Ti0.30O3 (PMN-30PT) single crystal substrates by switch pulsed laser deposition (SPLD). Since the CFO nanopillars are insulating, and the SRO matrix conductive, this self-assembled nanopillar heterostructure served as a patterned electrode on PMN-PT, which then enhances the dielectric and piezoelectric constant of the substrate. Cross-sectional electron microscopy images revealed the formation of a nanopillar heterostructure layer with CFO nanopillars within a SRO matrix. AFM and XRD revealed good topography and epitaxy, indicating a high quality SRO-CFO self-assembled nanopillar structure. Using a SRO-CFO thin film patterned electrode, PMN-PT was found to have a notably higher (30%) dielectric constant with increasing electric field and enhanced transverse broadening in reciprocal spacing mapping (RSM) scans. 相似文献
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水溶性氨基丙烯酸漆的研制 总被引:7,自引:0,他引:7
研制了高温烘烤 (145~ 15 0℃ )和中温烘烤 (12 0~ 12 5℃ )两种水溶性氨基丙烯酸漆。当羟基树脂的玻璃化温度为 - 5~ 0℃ ,丙烯酸和丙烯酸羟乙酯占总单体的质量分数分别为 7 5 %~ 8 5 %和 8 0 %~ 12 0 % ,羟基树脂和氨基树脂的质量比为 (0 0 5∶1 0 0 )~ (0 10∶1 0 0 ) ,颜基质量比为 0 2 9∶1 0 0时 ,两种漆的附着力达到 1级 ,抗冲击强度 >490N·cm ,柔软性 <1mm ,硬度 >2H ,光泽度 >80 (45℃ ) ,耐水 (2 0~ 2 5℃ ) 1d以上 ,遮盖力及施工性能良好 相似文献
48.
C.M. Wichern B.C. De Cooman C.J. Van Tyne 《Journal of Materials Processing Technology》2005,160(3):278-288
A hot-dipped galvanized zinc-coated sheet steel was deformed with three different laboratory test systems: a Marciniak punch system, a flat-die friction test system, and a cupping system. These systems were able to impose various combinations of deformation modes to the sheet. The deformation modes include: (1) strain without die contact, (2) sliding, (3) pressing, and (4) bending. Strain measurements from the electrolitically gridded specimens were made at the same locations as surface profilometry measurements, allowing a direct correspondence of surface roughness with strain. Quantification of the roughening as a function of strain, sliding and bending was determined. The roughening rate depends upon the strain level as well as the strain path. Increased strain without die contact causes an increase in the surface roughness with strain paths close to plane strain exhibiting the highest roughening rate. The deformation modes of sliding, pressing, and bending cause a decrease in the surface roughness (i.e. smoothing) to occur. A first-order model is proposed to account for the surface roughness as a function of these deformation modes. 相似文献
49.
Lead-based paints and primers have long been used to protect steel structures from corrosion, but are now recognized as environmental
hazards. During lead-based paint removal via abrasive blasting, federal, state and local environmental requirements mandate
the use of containment structures to prevent contamination of air, soil, or water. The thermal spray vitrification (TSV) process
was developed and optimized in laboratory experiments to remove hazardous lead-based paint. TSV consists of thermal spraying
a molten glass onto the painted surface. As the glass strikes the substrate, it reacts with the paint, and organic components
are pyrolyzed, while lead ions are trapped on the glass surface. Quenching stresses in the glass cause it to crack and spall
off the substrate. The resulting glass fragments are collected, and further remelted to completely immobilize lead (Pb) ions
in the glassy iron (Fe) silicate matrix. The glass waste is thus rendered non-hazardous, as determined by the Toxicity Characteristic
Leaching Procedure (TCLP). The TSV process was field tested on a fire hydrant, using minimal personal protective equipment
and without using a containment structure. The lead-containing paint was removed, without producing hazardous waste, leaving
de-painted surfaces suitable for repainting. 相似文献
50.
简要介绍了唐山钢铁集团公司新近建设的 14 0万t连续酸洗线、 60万t冷轧线、 45万t热镀锌线和 15万t彩涂线的工艺流程和生产线主要技术参数 相似文献