提高涂层防腐性能评价技术的探讨

界面防腐技术是油气田三维大跨度的大型结构群体综合防护治理的主要方法之一，但我国现行的涂层检测方法还存在较大的局限性和失真度，不能反映实际工况下涂层的防护质量。文章指出了我国涂层与防护质量评价技术的现状和与国外的差距，介绍了80年代以来国外在涂层质量评价方面采用的一些新技术和先进的综合评价方法，最后提出了采用表面分析技术和电化学方法相结合的评价技术，以及对现行评价方法的再创造等建议。     

LASER CLADDED TiCN COATINGS ON THE SURFACE OF TTTANIUM

Laser cladded coatings of TiCN were produced on the surface of titanium. To obtain the optimal techniques, several conditions were tested by varying the laser scanning rate. The choice of shielding gas was also studied. The cladded coatings were then evaluated from the surface mechanics point of view based on their microhardness. The microstructure of some interesting samples was investigated by optical micrographs （OM）. The results showed that under the condition of fixed pulse frequency and pulse width, the laser scanning rate and the shielding gas are the main factors influencing the components of coatings. TiCN coatings were decompounded and oxidized during the cladding process in the condition of no shielding gas of N2. X-ray diffraction results indicated that the composite coatings composed of TiCN, TiC, Ti2N, and TiO2 were produced using appropriate techniques. The results indicated that the best condition in terms of the surface microhardness is obtained when the scanning rate is 1.5mm/s, the pulse frequency is 15Hz, the pulse width is 3.0ms, and N2 is chosen as the shielding gas. The microhardness of the composite coatings is about 1331kg · mm^-2, which is about 4 times that of the substrate. The optical micrographs indicated that the cladding zone is made up of TiCN, TiO2 and some interdendritic Ti, but the diffusion zone mainly consists of the dendrites phase, and the cladded depth is about 80μm, which is more than 2 times that of the laser nitrided sample. There were no microcracks or air bubbles in the cladded sample, which was cladded using the above optimal techniques.     

化学镀Ni-P-PTFE复合镀层的性能

本文对化学镀ＮｉＰＰＴＦＥ复合镀层的性能作了测定和评价。实验表明，用优化的镀液配方和工艺可获得含ＰＴＦＥ粒子２５～３０％ｖｏｌ的ＮｉＰＰＴＦＥ复合镀层。这种镀层具有优良的结合力和良好的耐蚀性，其硬度随ＰＴＦＥ含量增加而降低，其特别突出的性能是优异的减摩性和耐磨性，是一种具有自润滑功能的表面复合材料。     

Investigation of the stability of tablets prepared from sucrose and citric acid anhydride utilizing response surface methodology

Inversion of sucrose is a stability problem particularly of candies with acidic taste that contain sucrose and small amounts of organic acids such as citric acid, since the free d-fructose produced by hydrolysis is hygroscopic. The following possibilities were investigated for preventing the hydrolysis of sucrose in tablets containing sucrose and citric acid: Adding various amounts of tri-sodium citrate to the formulation to neutralize the citric acid, (Hot) melt coating of citric acid and tri-sodium citrate with a vegetable fat at different coating ratios, variation of the ratio of coated citric acid and tri-sodium citrate in formulations, and compressing the formulations with different compression forces. After tablet processing and storage of tablets, the concentration of d-fructose was determined on the basis of enzymatic reactions. A response surface central composite design was used. The above-mentioned variations were chosen as independent variables and the amount of d-fructose was chosen as response variable. The lowest rates of inversion could be achieved by increasing the content of tri-sodium citrate and the ratio of coating material and decreasing the ratio of coated citric acid and tri-sodium citrate in the tablet formulations. The compression force had no significant effect on the inversion of sucrose.     

In-situ birefringence microscopy of uniaxially stretched metal-polymer laminate

This paper concentrates on revealing the local deformation as a function of applied strain in a polymer coating supported by a plastically deforming and roughening metal substrate. To this end in-situ birefringence microscopy measurements have been executed. The measurements are performed in reflection and an alternative unwrapping scheme for the optical path difference is proposed. From the characterization of PET (polyethylene terephthalate) coated stainless steel it is concluded that strain localization appears below the macroscopic strain at yield and that the surface roughness of the substrate is the driving force of the localization.     

Effect of Y2O3 Content on Microstructure of Gradient Bioceramic Composite Coating Produced by Wide-Band Laser Cladding

Hydroxyapatite (HA) ,a kind of bioactive materi-al , has wide application prospect in hard tissue re-placemen and repairment due to its si milar chemicalcomposition and crystallographic structure to that ofbone mineral[1 ,2]. Since HA has lowstrength (50 …     

钢结构的防火及防火涂料的涂装

详细了介绍了锦州石化公司体育馆及附属设施钢架结构的防火及防火涂料涂装;讨论了钢架结构的防火,并且制定涂层的设计方案、施工工艺及质量验收标准等。     

高性能鳞片涂料在脱硫烟囱防腐蚀中的应用

分析了湿法烟气脱硫工艺对脱硫装置及烟囱的腐蚀情况，对几种典型的衬里结构进行比较，介绍了高性能防腐蚀鳞片涂料的应用要求和工程实例。     

Comparison of interfaces in Ti composites reinforced with uncoated and TiB2/C-coated SiC fibres

Interfaces play an important role in determining the mechanical properties of composite materials. The interfaces established between a titanium-alloy matrix (Ti-6Al-4V) and uncoated and TiB₂/C-coated SiC fibres are analysed by scanning electron microscopy, transmission electron microscopy and X-ray techniques. Emphasis is placed upon the interfacial morphology and microstructure, identification of reaction products, and the stability of the coating layer. Complex multi-reaction layers are observed frequently in the interfacial zones. Previous, often contradictory, reports about the interlayers are reviewed. Experimental observation demonstrates that the type and distribution of interlayers vary in a given system, due to prolonged treatment of the samples at temperature. The formation and distribution of the interlayers are discussed further, with respect to these and previous findings. Methods of reducing interfacial reactivity are discussed.