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铈元素对热浸锌–铝–镁合金镀层显微组织及耐蚀性的影响 总被引:1,自引:0,他引:1
在Zn–Al–Mg镀液中添加不同量的稀土Ce以提高热浸镀Zn–Al–Mg合金层性能。通过分析合金镀层的表面形貌和截面形貌以及中性盐雾试验,系统地研究了镀液中Ce添加量对合金镀层显微组织结构和耐蚀性的影响。当铈的添加量≤0.05%(质量分数)时,随铈添加量增大,热浸镀Zn–Al–Mg合金层的晶粒逐渐细化,尺寸逐渐均匀;δ相层的厚度变化不大,而ζ相层略微减薄。当铈添加量0.05%时,随铈添加量增大,镀层合金相厚度骤减。中性盐雾试验表明,镀液中添加Ce有利于提高Zn–Al–Mg合金镀层的耐蚀性,但其添加量不宜超过0.05%。 相似文献
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以分析纯Fe2O3,NiO,ZnO,Al2O3,Pr6O11和WO3为原料,以Ni0.5Zn0.5MxFe2–xO4(M=Al,Pr,W;x=0~0.04)为基本配方,采用一步合成法制备了Ni–Zn铁氧体陶瓷,研究了掺杂对Ni–Zn铁氧体相组成、显微形貌和电磁性能的影响。结果表明:掺杂Al3+,Pr3+和W6+的Ni–Zn铁氧体均能形成结晶完好的尖晶石相结构。材料致密,无晶粒异常长大。适当的金属阳离子替代可有效降低材料的磁损耗和介电损耗,提高截止频率,同时使铁氧体保持较高初始磁导率,高饱和磁化强度,高Curie温度等优良性能,从而制得高性能大功率高频Ni–Zn系铁氧体磁芯。 相似文献
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《合成材料老化与应用》2016,(3)
通过对Y变质后的Mg-7Al合金进行固溶和时效处理,研究热处理对Y变质后合金组织及力学性能的影响,结果表明,固溶和时效对高熔点的Al2Y相均无明显影响。而时效处理后β-Mg17Al12相以层片状和点状共存的方式再次析出,改善了其原本粗大的网状形貌,且随时效温度升高,层片状β-Mg17Al12相数量减少,而点状析出量增多,因此,时效后合金力学性能得到提高。 相似文献
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《电镀与涂饰》2019,(21)
采用电感耦合等离子体发射光谱(ICP-AES)法测定热镀Zn–Al–Mg合金镀层的Al、Mg和Fe含量。先采用含3.5 g/L六次甲基四胺和250mL/L盐酸的溶液将Zn–Al–Mg合金层从钢基体上剥离,再分别在396.152、285.213和259.940nm波长下测定Al、Mg和Fe的含量,以基体匹配法来消除基体干扰。各元素校准曲线的线性相关系数均大于0.999 5,Al、Mg、Fe的检出限分别为0.018 0、0.007 8和0.009 6 mg/L,测定下限分别为0.090、0.039和0.048 mg/L。该法的加标回收率在96.5%~104.5%之间,相对标准偏差在0.47%~4.02%范围内。 相似文献
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钢结构件热浸镀阳极性铝合金镀层技术的研究 总被引:1,自引:0,他引:1
在热浸镀纯铝的工艺条件下,通过在铝液中加入Zn、In、Sn等合金元素,制备了3种阳极性铝合金镀层:Al–5%Zn–0.02%In、Al–4%Zn–0.06%Sn及Al–5%Zn–0.06%Sn。使用光学显微镜、3.5%Na Cl全浸腐蚀试验及电化学工作站检测了所得铝合金镀层的组织及性能,并与纯铝、纯锌及55%Al–43.4%Zn–1.6%Si镀层进行了对比。结果表明,镀层的最佳组成分别为Al–5%Zn–0.02%In和Al–(4%~5%)Zn–0.06%Sn。在3.5%Na Cl溶液中,其耐蚀性优于55%Al–43.4%Zn–1.6%Si镀层,而腐蚀电位相当;在Cl–浓度为零时未发生铁铝极性逆转,镀层的显微组织与纯铝镀层相同。该热浸铝合金镀层的热浸镀工艺与热浸镀铝完全相同,使用热浸镀铝的设备及工艺即可实现工业生产。 相似文献
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利用真空熔炼法制备了含钕稀土镁合金,研究了钕对Mg-Al合金微观组织和力学性能的影响。结果表明,稀土钕加入Mg-Al合金时,有Al3Nd相生成,显著地细化了α-Mg相基体晶粒,Mg-Al合金的显微硬度从50.6HV增加到137HV。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%. 相似文献
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塔设备改造选型的分析 总被引:2,自引:0,他引:2
就当前扩产增容中塔设备设计和改造时板式塔和填料塔的选型问题加以分析。在评述目前国内常用的几种塔板和新型填料之后,着重介绍一种新型塔板(导向梯形浮阀塔板)和一种新型填料(波环填料——乾隆帕克)。 相似文献