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1.
镀锌钢板表面耐腐蚀稀土镧盐转化膜的制备   总被引:1,自引:0,他引:1  
采用稀土镧在镀锌钢板表面制备耐腐蚀的转化膜,通过交流阻抗、失质量和盐雾实验检测镧盐转化膜的耐腐蚀性能,实验结果表明:试样表面生成镧盐转化膜后,其阻抗值相对于空白试样大幅度提高,腐蚀速率降低近1个数鼍级,抗白锈时间达到54 h;原子力显微镜检测结果显示镧盐转化膜由大量无定形的固体颗粒沉积而成,膜质不均匀;EDS能谱检测结果表明镧盐转化膜由O、Fe、Zn和La元素组成.  相似文献   

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在硫酸电解液中采用硬质阳极氧化技术对铝合金进行了表面处理,并研究了电流密度对阳极氧化膜性能的影响。结果表明:当电流密度为1.5 A/dm~2时,阳极氧化膜表面最光滑,显微硬度最大,自腐蚀电位最正。当电流密度为2.0 A/dm~2时,交流阻抗曲线的弧度最大。可见,当电流密度为1.5~2.0 A/dm~2时,阳极氧化膜的耐蚀性较好。  相似文献   

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何琼 《电镀与精饰》2021,43(9):19-24
选取在建筑领域常用的6463铝合金作为研究对象,为使其耐蚀性能得到显著提高,进行酒石酸阳极氧化然后采用镍盐封闭,同时进行硫酸阳极氧化及镍盐封闭作为对比.表征和测试了酒石酸氧化膜、硫酸氧化膜的显微形貌、成分和耐蚀性能,并研究了封闭对酒石酸氧化膜和硫酸氧化膜的影响.结果表明,Ni元素通过封闭被引入氧化膜中,封闭后硫酸氧化膜和封闭后酒石酸氧化膜都含有Al、O、S、Ni四种元素.封闭后酒石酸氧化膜和硫酸氧化膜都呈现"花瓣状形貌",且明显不同于铝合金的显微形貌.封闭使得氧化膜的腐蚀电位明显正移,极化电阻提高到接近104Ω·cm2数量级,腐蚀速率明显降低.相比于封闭后硫酸氧化膜,封闭后酒石酸氧化膜表面更均匀致密,具有优良的耐蚀性能,对铝合金的防护性能更好.  相似文献   

4.
本文采用极化曲线测试、交流阻抗测试和腐蚀成分分析等试验手段对5083铝合金在不同p H值海水中的腐蚀行为进行了研究,对铝合金浸泡前后的表面形貌进行了表征,并对腐蚀成分进行了分析。结果表明:随着p H值的升高,铝合金的腐蚀情况逐渐加剧,耐蚀性减弱,腐蚀电位发生负移,维钝电流密度增大,阻抗弧急剧减小,在低频区出现了Warburg阻抗;在p H值=7的人造海水中,5083铝合金的腐蚀主要以点蚀为主,随着p H值的升高,铝合金腐蚀开始以均匀腐蚀为主,铝合金基体表面发生晶间腐蚀。  相似文献   

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铝合金表面钛酸盐化学转化膜研究   总被引:7,自引:4,他引:7  
基于含铬处理对环境影响的考虑,世界范围内都在积极开发有效的替代技术,用于铝合金腐蚀保护从而代替铬酸盐转化处理。研究了铝合金钛酸盐处理技术。通过循环极化曲线和盐雾试验测定,钛酸盐和铬酸盐化学转化膜都有非常宽的钝化区,在NaC l(c=0.5 mol/L)溶液中2种氧化转化膜均没有击穿电位;钛酸盐转化处理的样品经336 h盐雾试验表面无点腐蚀发生。钛酸盐转化膜可以为铝合金提供良好的腐蚀保护作用。  相似文献   

6.
通过线性极化、动电位极化和交流阻抗等电化学测试方法研究腐蚀产物膜对X80钢腐蚀行为的影响,采用电子扫描显微镜和X-射线衍射仪对X80钢在鹰潭酸性红壤模拟溶液中浸泡不同周期后的表面腐蚀产物膜进行微观形貌观察。结果表明,腐蚀产物膜主要由Fe3O4和FeO(OH)组成,覆盖有腐蚀产物膜试样的电荷转移电阻、极化率及容抗弧半径均比处于全浸周期试样的小,腐蚀产物膜明显加速了X80钢在酸性红壤溶液中的腐蚀速率。  相似文献   

7.
为了提高6063铝合金的防腐蚀性能,制备了一种6063铝合金苯胺(BAN)封闭膜。采用极化曲线及交流阻抗技术研究了不同体积分数苯胺所制备的封闭膜的电化学性质。与去离子水中的封闭膜及基体的铝合金相比,极化曲线结果表明当苯胺的体积分数为0.12%~0.42%时,生成的苯胺封闭膜具有较正的点腐蚀电位及较低的腐蚀电流;交流阻抗谱数据也显示当苯胺的体积分数为0.12%~0.42%时,封闭膜具有较高的腐蚀阻抗,说明苯胺封闭膜具有较好的耐腐蚀性能。全浸失质量速率测试结果也表明苯胺封闭膜对6063铝合金有一定的防护作用。采用扫描电镜对样品的表面形貌进行了测试,测试结果与其电化学现象一致。  相似文献   

8.
通过酸性盐雾试验研究了经苹果酸-硫酸体系阳极氧化处理的7050-T7451铝合金在模拟舰载环境中的腐蚀行为。通过扫描电子显微镜、电化学阻抗谱测量和疲劳性能测试分析了经酸性盐雾腐蚀不同时间后阳极氧化膜结构和基体疲劳寿命的变化。结果表明,阳极氧化膜对铝合金基体具有很好的保护作用,能够保护铝合金基体在酸性盐雾试验的4个周期(192 h)内免受腐蚀。随着酸性盐雾试验时间的延长,阳极氧化7050-T7451铝合金的疲劳寿命逐渐衰减,其演化规律与腐蚀行为的变化基本吻合。  相似文献   

9.
添加剂对镀锌层钝化膜耐蚀性的影响   总被引:1,自引:1,他引:0  
利用极化曲线和交流阻抗谱,研究了不同添加剂对镀锌层烷氧基硅烷钝化膜腐蚀性能的影响,并与加速腐蚀试验结果进行了对比.实验结果表明:添加剂的加入明显改变了钝化膜层的腐蚀电位,提高钝化膜在低频区的交流阻抗值,烷氧基硅烷钝化膜的耐蚀性明显提高.  相似文献   

10.
为了提高6063铝合金的防腐蚀性能,在6063铝合金水浴封闭过程中加入乙胺缓蚀剂。采用极化曲线及交流阻抗测试技术研究了封闭膜的电化学行为。与去离子水封闭膜及铝合金基体相比,当乙胺质量浓度为2.5~4.5 mL/L时生成的封闭膜具有较正的点腐蚀电位及较低的腐蚀电流,说明封闭膜具有较好的耐腐蚀性能。  相似文献   

11.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

16.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

17.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

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Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.  相似文献   

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