Papers by Keyword: Coating

Abstract: In this study, the performance and exhaust emissions of a biodiesel fuelled low heat rejection (LHR) direct injection Diesel engine have been investigated experimentally and compared with the results of standard diesel engine without any coatings. Piston, cylinder head, exhaust and inlet valve of test engine were coated with 0.5 mm thickness of zirconia through plasma spray method. Biodiesel used in the testing was prepared from rice bran oil through transesterification process.

Abstract: The fundamental theory about the constitutive relationship of hyperelastic model has been introduced and the model of super-elastic coating has been simulated in this paper. The static stiffness of different coating thickness has been calculated considering the hyperelasticy and viscoelasticity. Through the studying, because of the increasing of deformation, the compression static stiffness of the hyperelastic coating will be increased; while the tension static stiffness of the hyperelastic coating will be decreased. Moreover, the static stiffness is only related to the relative deformation not the absolute deformation.

Abstract: The physical properties of waste concrete recycled aggregate according to the mixing ratio of the coating agent and the number of coatings investigated in this study. As the result, the Density of recycled aggregate increased, as the mixing ratio of the coating agent and the number of coatings increased. The percent of water absorption decreased rapidly for all coating conditions, and potential contamination test showed that among 21 items of concern, five were detected. The compressive strength of the water-permeable concrete increased by approximately 16.2% as produced with coated recycled aggregate.

Abstract: The epoxy resin (ER) and 2,3-epoxypropoxypropytrimethoxysilane (KH-560) were used to prepare alkyd resin (AR) insulating coating. The modified waterborne alkyd resin insulating coating was prepared. The dynamic mechanical properties, thermal properties and electrical properties of the composites were characterized by DMA, TG, et al. The results show that the tertiary amine has a good catalyzing effect for this reaction. When the mass ratio of AR with ER is 1 : 1, the glass transform temperature T_g of material is 64.6 °C. When the content of KH-560 is 5% mass fraction of the alkyd resin, the T_g of composites increase 5.6 °C, the initial degradation temperature increased by 63.78 °C; The r_s and r_v of composites are between 10⁹ ~ 10¹² MΩ; the ε and tanδ is between 0.6553 ~ 0.9975 and 0.0025-0.0036, respectively. The pencil hard degree and the impact strength of coating film are all over 5H and 40N, respectively.

Abstract: Al7075 alloy has typically good mechanical properties. Al7075 alloy has an ultimate tensile strength and yield strength, which is commonly used in the manufacturing of heavy-duty structures requiring good corrosion resistance and in applications requiring high strength to weight ratio, as well as good fatigue resistance. However, as compared to strength and corrosion of conventional steel material, it has some drawbacks. To overcome these disadvantages, Electrolytic plasma processing (EPP) was used. (EPP) is a novel electrochemical and physical surface treatment process for generating protective coatings on light metals. Because, these coating scan present high hardness and continuous barriers, it can offers good protection against abrasion, corrosion and heat as well as electrical insulation. The EPP treatments were carried out under a hybrid voltage of AC 200V (50Hz) combined with DC 260V power supply.

Abstract: In this paper the anticorrosion properties of steel bars coated with polymer modified cement-based coatings in chloride solution were evaluated. Then the pullout tests were conducted using coated and uncoated steel bars embedded in concrete specimens and the bond properties between concrete and bars were tested. The results show the steel bars coated with epoxy emulsion modified cement-based coating (HY) and elastic copolymer emulsion modified cement-based coating (GT) have satisfactory anticorrosion properties in 3.5% NaCl solution for 96h. But the pullout tests display that the bond strength between the concrete and the steel bars coated with GT coating is much lower than that of the bars coated with HY coating and the uncoated specimens. The bond stress between the concrete and the bars coated with pure acrylate emulsion modified cement-based (CB) coating is the highest among the three coatings, but the resistance to chloride permeability of CB coating is poor. The results indicate the special epoxy-cement-based coating (HY) is more suitable for applying to the anticorrosion coating for steel bars in chloride condition.

Abstract: In order to improve anti-corrosion property of magnesium alloy parts in equipment, Al-based alloy coating on ZM5 magnesium alloy was prepared by supersonic particles deposition (SPD). Mass gain after being corroded, surface morphology of samples corroded and corrosion products were investigated by salt-mist test, SEM observation and EDS analysis etc. The results indicated that the mass gain of Al-Si coating after being corroded decreased evidently compared with magnesium alloy substrate. Al-Si coatings with thickness above 0.5mm did not generate blisters after 500h salt-mist test, proving that the coating possessed excellent anti-corrosion property.

Abstract: Polypropylene/polysulfone composite ultrafiltration membrane was prepared though coating method using microporous polypropylene hollow fiber membrane as a support layer and polysulfone membrane as a functional layer. Membranes of different pore sizes were prepared by L-S phase translation though changing the concentration of PS. The properties of the composite membrane include water flux and rejections of PEG-2000 were studies. The flux of 78 L/m²h and 98 % rejection was achieved at PS concentration of 11%, Polyvinylpyrrolidone of 4 %, liquid phase coagulation time of 3 hours.

Abstract: Three-dimensional short carbon fiber felt reinforced C/SiC composites were prepared by the liquid silicon infiltration (LSI) process. The influences of different porosity ratios, carbon coating, and heat treatment of C/C substrates, on the properties of C/SiC composites were studied. The optimized porosity ratio is calculated as 40.1% when the volume percent of carbon fiber (including carbon coating) is 23%, and after screening porosity ratio from ~55% to ~20%, the optimized experimental result (39.5%) is highly in accordance with the design value. The C/SiC composite after process parameter optimization, has a flexural strength and modulus of 125 MPa and 120 GPa, respectively. The C/SiC composite without carbon coating has a flexural strength of only 77 MPa, showing carbon coating plays a key role. The heat treatment of C/C substrate at 1600°C also improves the flexural strength of C/SiC composite for nearly 50%, and porosity rearrangement and interface weakening are believed to contribute such improvement.

Abstract: The effect of calendering temperature, speed and linear load on the properties of opacity, brightness, smoothness, paper thickness, gloss and ink absorption of art paper were studied by orthogonal experiment. The art paper coating formulations were as follows: GCC-60 100 pph, solid content 64.6% for precoating; GCC-95 40 pph, Kaolin 60 pph, and solid content 61.3% for top coating. Bar coater was involved to coat by hand in the lab and the coating weight was controlled at 20±2g/m². After calendering in different conditions, the optical properties and printability of paper were analyzed. Regression analysis was used to study which of the calendering conditions was the dominant factor influencing the paper properties. The results showed that linear load was the dominant one, followed by the calendering temperature and calendering speed. After calendering, smoothness and gloss increased, while the brightness and opacity decreased.