海上风电塔架腐蚀与防护现状

海上风电作为一种绿色能源技术,已成为世界上可再生能源发展的热点。海上风电运行在高度腐蚀的海洋环境中,防腐蚀成为一项非常重要的工作,而塔筒是防护的重点。本文分析了海上风电塔架的腐蚀原因和防腐蚀设计,综述了海上风电塔架防腐蚀用富锌涂料和聚氨酯涂料的研究进展,提出通过纳米材料和缓蚀剂改性优化提高防腐蚀涂料综合性能的建议,为海上风电塔架提供更好的腐蚀防护。     

一种新型永磁电机转子的研制

介绍了一种新型的永磁电机转子结构,在转子的外圆表面加工有纵向错齿分布的燕尾槽,转子外的磁钢分段插入燕尾槽中,末端用挡圈固定.该结构磁钢安装固定方便,避免了磁钢脱落事故的发生,磁钢的分段错齿分布也有效地提高了电机运转的平稳性,同时降低了电机的振动和噪声.     

铝镍钴磁钢的真空熔铸

一、前 言 航空用电机转子磁钢质量的优劣,直接影响电源的特性。由于电机转速高,通常在10000转/分以上,因而要求磁钢不但要有高的磁性,还要有一定的机械强度和良好的表面质量,尤其是多极磁钢(图1所示)的极面上,不允许有缩孔、气孔和氧化夹杂物等表面缺陷。我厂生产的转子磁钢磁性一直比较稳定,但多因磁钢铸件的表面缺陷造成大批废品。     

防腐涂料用聚氨醋-环氧树脂复合乳液的合成研究

以甲苯二异氰酸酯、聚醚二元醇、二羟甲基丙酸和乙醇为主要原料合成了部分封端的亲水性聚氨酯预聚体,然后接枝环氧树脂,再水分散并经乙二胺打开环氧基交联,得到聚氨酯-环氧树脂复合乳液.研究了环氧树脂中羟基的接枝率和环氧树脂用量对乳液和涂膜性能的影响.研究发现,随着接枝率提高,乳液外观改善,稳定性提高,涂膜的防腐蚀性能增强.随着...     

高速永磁电机转子强度分析

磁钢相对脆弱,保证磁钢结构强度在安全范围内是高速电机设计的一个要点。依靠护套和磁钢过盈配合产生的压力能确保高速电机磁钢不碎裂。为确保电机安全运行,必须根据转子转速、外径等参数对护套厚度和过盈量进行计算和校核。对3种常见磁钢结构进行比较,选择使用实心圆柱结构;通过计算和分析得出如何选择护套的材料、厚度、过盈量;考虑离心力、过盈配合,分析并设计某70 000 r/min永磁同步电机的转子。研究结果为设计高速永磁电机的磁钢和护套提供参考。     

耐沾污、自洁净防腐蚀涂料

通过引入具备表面迁移及水解功能的有机硅,研制出耐沾污、自洁净聚氨酯防腐蚀涂料Durashield ADS,该防腐蚀涂料具有雨水自洁净效果.     

三种环氧改性聚氨酯基低红外发射率涂层的腐蚀电化学行为

采用电化学阻抗谱(EIS)研究了以环氧树脂(EP)、改性聚氨酯(PU)为粘合剂,铜粉、硅烷偶联剂改性铜粉、丙烯酸改性铜粉为填料的三种低红外发射率涂料在模拟海水环境(3.5%NaCl溶液)中的电化学腐蚀行为,并比较了这三种涂层体系的防腐蚀性能。结果表明,浸泡初期,铜粉填充环氧改性聚氨酯基涂料表现出较好的防腐蚀性能,但随着浸泡时间延长其失效速度加快,在整个浸泡过程中防腐蚀性能最差。根据涂层电阻(Rcoat)和涂层特征频率(fb)推测,丙烯酸改性铜粉填充环氧改性聚氨酯基涂料的防腐蚀性能优于硅烷偶联剂改性铜粉填充环氧改性聚氨酯基涂料。     

海上风电防腐蚀设计

近年来全世界海上风电的蓬勃发展,但严酷的海上环境却给海上风电带来了新的挑战,腐蚀问题已成为海上风电遇到的难题之一。本文从海上风电的组成角度出发,系统地探讨了腐蚀环境以及海上风机、海上升压站、海缆的防腐蚀设计,并提出未来海上风电防腐蚀设计展望。     

丙烯酸聚氨酯涂料防腐蚀性能研究

利用电化学阻抗谱(EIS),研究了对添加不同颜料体积浓度( PVC)TiO2的丙烯酸聚氨酯涂料的防腐蚀性能.实验结果表明,PVC为40%的涂层具有最优的 防腐蚀性能.     

降低热喷涂涂层孔隙率的方法

热喷涂的工作原理决定了其涂层孔隙是不可避免的。当涂层用于防腐蚀时,腐蚀介质会通过孔隙到达基体表面,从而造成防护失败。因此,封孔处理是提高涂层防腐蚀性能的重要途径。本文总结了涂层封孔处理的方法,对未来涂层封孔技术进行了展望,并提出一种新的涂层封孔剂——釉。     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

Rheology Feature of Simple Metal Melt

The rheology feature of Sb, Bi melt and alloys was studied using coaxial cylinder high-temperature viscometer. The results showed that the curve of torsion-rotational speed for Sb melt presents a linear relation in all measured temperature ranges, whereas for the Bi melt, the curve presents obvious non-Newtonian feature within the low temperature range and at relative high shear stress. The rheology feature of Sb80Bi20 and Sb20Bi80 alloy melts was well correlated with that of Sb and Bi, respectively. It is considered that the rheology behavior of Sb melt plays a crucial role in Sb80Bi20 alloy and that of Bi melt plays a crucial role in Sb20Bi80 alloy.     

Microstructures and Mechanical Properties of a Newly Developed Austenitic Heat Resistant Steel

The effect of heat treatment on the microstructures and mechanical properties of a newly developed austenitic heat resistant steel(named as T8 alloy) for ultra-supercritical applications have been studied. Results show that the main phases in the alloy after solution treatment are γ and primary MX. Subsequent aging treatment causes the precipitation of M_(23)C_6 carbides along the grain boundaries and a small number of nanoscale MX inside the grains. In addition, with increasing the aging temperature and time, the morphology of M_(23)C_6 carbides changes from semi-continuous chain to continuous network.Compared with a commercial HR3C alloy, T8 alloy has comparable tensile strength, but higher stress rupture strength. The dominant cracking mechanism of the alloy during tensile test at room temperature is transgranular, while at high temperature, intergranular cracking becomes the main cracking mode, which may be caused by the precipitation of continuous M_(23)C_6 carbides along the grain boundaries. Typical intergranular cracking is the dominant cracking mode of the alloy at all stress rupture tests.     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

The 15th Global Foundry Sourcing Conference 2014held in Qingdao China

Organized by Suppliers China Co., Ltd and co-organized by the National Technical Committee 54 on Foundry of Standardization Administration of China, the 15th Global Foundry Sourcing Conference 2014 （hereinafter referred to as FSC 2014） was successfully held on Sep. 23rd in Grand Regency Hotel, Qingdao. More than 500 delegates from home and abroad attended this conference, including over 130 purchasers from 20 countries and 380 domestic and foreign suppliers.     

Secondary Recrystallization Behaviors of Grain-Oriented 6.5 wt% Silicon Steel Sheets Produced by Rolling and Nitriding Processes

By rolling and nitriding processes, 0.23- to 0.3-mm-thick grain-oriented 6.5 wt% silicon steel sheets were produced. The core losses of grain-oriented 6.5 wt% silicon steel at frequencies ranging from 400 Hz to 20 k Hz were lower than that of the grain-oriented 3 wt% silicon steel with the same thickness by 16.6–35.8%. The secondary recrystallization behavior was investigated by scanning electron microscopy, energy-dispersive spectroscopy, and electron backscattered diffraction. The results show that the secondary recrystallization in high-silicon steel sheets develops more completely as the nitrogen content increases after nitriding, secondary recrystallized grain sizes become larger, and the sharpness of Goss texture increases. Because more {110}116 grains in the subsurface and the central layer of the sheets have a lot of 20°–45° high-energy boundaries in addition to Goss grains, {110}116 can be the main component through selective growth during secondary recrystallization when the inhibitor quantity is not enough and inhibitor intensity is weaker. The increases in nitrogen content can increase the inhibitor intensity and hinder abnormal growth of a mount of {110}116 grains and therefore enhance the sharpness of Goss texture.     

Laser Cladded TiCN Coatings on the Surface of Titanium

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 80?滋m, 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.     

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.     

Information for Contributors

正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis