Abstract: nanoZrO2 was modified by styrene coupling grafting method and then used as an additive to improve the protective performance of epoxy coating. Two kinds of coatings, neat epoxy coating and nanoZrO2/epoxy coating, were prepared and applied on Q235 carbon steel plates. The plates were submitted to salt spray chamber and seawater immersion for 1000 hours to evaluate the corrosion protection performance for these two kinds of coatings. Tafel polarization curves and electrochemical impedance spectroscopy (EIS) were determined to analyze the corrosion behavior of coating/metal system. Scanning electron microscopy (SEM) and photographs were carried out for morphology analysis of two kinds of coatings under different conditions. Results showed a superior stability and efficient corrosion protection by nanoZrO2 /epoxy coating. The modified nanoZrO2 could inhibit the penetration of corrosive media and then improve the corrosion protection of the epoxy coating on carbon steel.
Abstract: With the development of technology, steel structures have been gaining increasingly widespread application, and the scope of research of steel types is also becoming increasingly broad. In addition to the four common steels used in construction, various mechanical properties and practical application of Q460 steel have also been studied at home and abroad at present. This paper introduces the research status of Q460 steel, describes its mechanical properties and the requirements for steels used in steel building structures, and analyzes the main factors influencing the properties of Q460 steel, providing some reference for practical engineering application of Q460 steel.
Abstract: The history of aluminium-lithium alloys development has been reviewed in this paper. According to the strength, weld ability and corrosion resistance, thermal stability and plasticity, aluminium-lithium alloy has been categorized and the defects of aluminium-lithium alloys in early stage have been analyzed. As compared the third generation of aluminium-lithium alloy with normal aluminum alloy and composite materials, it indicates aluminium-lithium alloy has better performance, lower cost and reduced weight. After analyzing the advantages and disadvantages of the rapid solidification, ingot casting metallurgy and electromagnetic simulated microgravity methods in synthesis of aluminium-lithium alloy, it has been found microgravity method has prominent effect on reducing the alloy segregation and lithium losses. Finally, the future development of aluminium-lithium alloys has been discussed.
Abstract: In this paper, meso-porous MCM-41 was synthesized at room temperature using cationic surfactant cetyltrimethylammonium bromide (CTAB) as the template agent. Then MCM-41/unsatura-ted polyester resin (UPR) materials were prepared by in-situ polymerization with the meso-porous MCM-41. MCM-41/UPR in-situ composites were prepared by roller milling and molding processes. Effects of meso-porous MCM-41 on rheological properties and wear resistance of the MCM-41/UPR composites have been investigated. It is shown that MCM-41 has a diameter in range of 4-5 nm and the pores are highly ordered. MCM-41 can improve the rheological properties and wear resistance of the composites. When MCM-41 content is 2%, the mass abrasion loss is decreased by 37.4%.
Abstract: The direct laser drilling could bring the recast layer and micro cracks, here introduced a new method named low-pressure water jet assisted laser drilling.It mainly studied some factors influence on the surface and inwall morphologies of Al2O3 ceramic when using low-pressure water jet, such as auxiliary gas pressure、pulse energy、repeated frequency.By optimizing the parameters, it can get the better surface and inwall morphologies. The results show that, taking advantage of the erosion of water jet, the composite drilling can obviously lessen molten slags, in order to reduce the recast layer and micro cracks, the processing quality can be improved much.
Abstract: Due to the special properties of asphere lens, the testing of it is more difficult than that of spherical lens. In this paper, the development of a new method using the liquid crystal spatial light modulator (SLM) to measure the accuracy of an aspheric surface is presented. The surface form was measured using a new component as the compensator lens in conjunction to provide an interferogram representing the aspheric form deviation from the nominal. Interferograms are decoded using a spatial-carrier phase shifting technique. The interferometric data is compared to data obtained using a contact stylus profilometer. The system can be mounted over a polishing machine and used for on-line testing of aspheric mirror surfaces.
Abstract: This paper presents the conclusions the tool wear of screw drill for steel X04Cr16Ni12MnTiN. The results of the article are conclusions for working theory and practice for drilling of steel X04Cr16Ni12MnTiN. Based on the cutting tests, cutting speeds of 50 to 90 m/min, feed rate of 0.02 to 0.8 mm and screw drill carbide monolite. Wear criteria are used in practice. For special cases may also prescribe criteria wear EA (Edge Annihiliation) corresponding to the total destruction of the tip cutting wedge.
Abstract: Comparative studies about different cadmium salts were carried out by chemical bath deposition method. The CdS nanofilms that deposited with Cd (Ac)2 was smoother, thicker and higher transmittance without any pin hole and particles compared with the films deposited with CdSO4. In this paper, The band gap energy was shifted from 2.4 eV to 2.3 eV while the CdSO4 was instead with Cd (Ac)2. In addition, the craystalline of the films deposited with Cd (Ac)2 was also better than that with CdSO4. Poly-crystalline hexagonal structure CdS without any unwanted secondary phases was demonstrated by GI-XRD analyses. Applications of the CdS nanofilms deposited with Cd (Ac)2 was carryout. Combined our previous test results, the film that deposited on the CIGS abosorb layer was well covered which can demonstrated better for solar cell application.
Abstract: Corrosion resistance of X52 pipeline steel at sea mud zone in Qingdao Huiquan test station was investigated by using Tafel polarization curves and electrochemical impedance spectroscopy (EIS). The morphology and chemical composition of the corrosion products were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results indicated that the corrosion current density of X52 pipeline steel increased with immersion time. The corrosion products were loose and mainly included Fe3O4, Fe2O3 and FeOCl, which absorbed on the specimen surface accelerating the cathodic depolarization reaction.