共查询到20条相似文献,搜索用时 62 毫秒
1.
使用X射线光电子能谱(XPS),对电工钢板铬酸盐涂层中的元素组成及铬元素的价态进行了研究,并对其形成机理进行了探讨。结果表明,涂层中主要含有Cr、O、Mg、Al、B以及C元素。在给定的处理工艺条件下,铬酸盐涂层钢板中铬元素主要是以Cr2O3,CrO3形态存在,在检测中没有发现零价铬。 相似文献
2.
3.
镀锡板钝化过程中的电流密度对钝化膜的性能影响较大,同时膜的性能又与厚度、成分、Cr元素含量等因素相关。实验通过改变镀锡板钝化膜生成过程中的钝化电流密度,探究电流密度对生成的钝化膜的厚度和成分的影响,并使用X射线光电子能谱(XPS)对在此电流密度下得到的钝化膜中Cr元素的组元和价态进行分析。结果表明在电流密度由3A/dm~2变为0.5A/dm2时:钝化膜厚度变薄,钝化膜中Sn元素含量增加,Cr元素含量减小;钝化膜中Cr元素的组元均由单质Cr、Cr_2O_3、Cr(OH)_3构成且不发生变化,但各价态组分的相对含量发生改变,低价态Cr含量降低,高价态Cr含量升高;镀锡板钝化膜组成成分呈现层状分布。 相似文献
4.
5.
6.
7.
镀锡板是指两面镀有一层极薄金属锡的冷轧薄钢板,它将钢的硬度和强度与锡的抗腐蚀性和光亮的外表集于一体。实验用电化学法将镀锡板的钝化膜、纯锡层、合金层逐层剥离,通过阴极极化曲线、交流阻抗等电化学技术研究其电化学性能,用扫描电镜(SEM)观察剥离后各层的表面形貌,用X射线光电子能谱仪(XPS)对镀锡板铬酸盐钝化膜中铬元素的价态进行了分析。结果表明,电化学法剥离的效果十分理想,可以用于镀锡板表面不同层的形貌观察,同时还可以用于镀锡板的耐蚀机理研究。除掉钝化膜后,腐蚀电流密度从1.48 μA/cm2增大到3.5 μA/cm2,除掉纯锡层后,腐蚀电流密度从3.5 μA/cm2增大到18 μA/cm2,镀锡板良好的耐腐蚀性主要来源于纯锡层和钝化膜的作用。镀锡板铬酸盐钝化膜中铬元素主要以氢氧化铬、金属铬和三氧化二铬等形态存在。 相似文献
8.
常规镀锌钢板所使用的铬酸盐处理对擦伤和其它受损部位的耐蚀层具有很好的自我修复作用,但由于铬酸盐膜中含有不环保的六价铬,欧洲到2 0 0 7年,将完全禁止其使用,因而,必须开发无Cr型涂层产品。为适应这个要求,川崎制铁开发了一种无铬型自润滑性涂镀层产品。该产品有如下特性:(1)涂层绝对不含铬;4 μm厚的润滑膜保证了良好的冲压成形性,冲压过程中不用涂油,并且在成形后有良好的外观和耐蚀性。(2 )与常规铬酸盐处理自润滑钢板相比较,摩擦系数减少一半,显示出优异的润滑性。(3)试验显示新产品有优异的润滑性,极限拉延压力比常规铬酸盐处理自… 相似文献
9.
10.
分别采用包套热挤压和热压烧结法制备FeCrNi中熵合金,研究制备工艺对合金组织结构及耐蚀性能的影响。结果表明:采用热挤压工艺制备的FeCrNi中熵合金平均晶粒尺寸为13μm,且存在粗大的退火孪晶,而热压烧结工艺制备的FeCrNi中熵合金晶粒组织更细小,平均晶粒尺寸为6μm。在0.5mol/L H2SO4+2×10-6 mol/L HF溶液中,热压烧结FeCrNi中熵合金表现出更好的耐蚀性,即更高的击穿电位(0.979V)、更低的腐蚀电流密度(7.68×10-6 A/cm2)以及更宽的钝化区ΔE(1.011 V)。热挤压FeCrNi中熵合金钝化膜中Cr元素主要以Cr(OH)3形式存在,而热压烧结FeCrNi中熵合金钝化膜中Cr元素主要以Cr2O3形式存在。这是因为热压烧结FeCrNi中熵合金的细晶组织具有高密度晶界,能够为Cr提供更多扩散通道,从而促进钝化膜中Cr2O3的... 相似文献
11.
实验结果表明,M17铸造高温合金(%:0.16C、8.79Cr、5.79A1、4.93Ti、3.29Mo、15.20Co、0.78V、0.015B、0.073Zr、0.002S、0.001P、0.001 1O、0.001 0N)经25 kg真空感应炉返回重熔后,Si含量随重熔次数的增加而略有增加,合金中主要元素和其它杂质元素S、P、H的含量变化不大,而氧、氮略有增加;合金中初生碳化物由新合金中的草书体逐渐向返回合金块状转变,初生碳化物的遗传性堵塞合金凝固时的补缩通道,使返回料合金的疏松倾向增大,高温塑性下降较大。 相似文献
12.
13.
14.
<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic 相似文献
15.
正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field, 相似文献
16.
《China Nonferrous Metals Monthly》2014,(10)
正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF 相似文献
17.
《China Nonferrous Metals Monthly》2014,(10)
正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure 相似文献
18.
《China Nonferrous Metals Monthly》2014,(10)
正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year, 相似文献
19.
《China Nonferrous Metals Monthly》2014,(12)
正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform. 相似文献
20.
正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness. 相似文献