Stainless steel surface passivation treatment
    2.
    发明授权
    Stainless steel surface passivation treatment 失效
    不锈钢表面钝化处理

    公开(公告)号:US5259935A

    公开(公告)日:1993-11-09

    申请号:US875506

    申请日:1992-04-29

    CPC分类号: C23C8/10

    摘要: The present invention provides a method for surface passivating stainless steel articles against the effects of corrosive materials having activities anywhere from aqueous salt solutions to corrosive gases such as hydrogen chloride and silane. Additionally, after the treatment and exposure of the article to moisture, when the article is subsequently flushed with a dry gaseous fluid, the time that the article takes to exhibit an acceptable moisture outgassing rate is reduced over an untreated article. In accordance with the present invention, the surface to be passivated is flushed with a dry gaseous fluid, chemically non-reactive with the stainless steel and containing essentially no oxygen. During such flushing, the articles is baked and cooled. The baking is accomplished at a predetermined temperature and time (preferably between about 250.0.degree. C. and about 500.0.degree. C. for about 4.0 hours) to effect, within the oxide layer, a reduction in adsorbed moisture and hydroxide content and an increase in chromium content. The article is allowed to cool after the baking step. Such gaseous fluid can comprise argon having a moisture content of no greater than 10.0 ppb and an oxygen content of about 10 ppb. No improvement was seen in a sample in which nitrogen was used. When nitrogen shows no improvement, the article should be flushed with a rare gas during baking which additionally should contain 10 ppb nitrogen or less.

    摘要翻译: 本发明提供了一种用于表面钝化不锈钢制品的方法,以抵抗具有从盐水溶液到腐蚀性气体如氯化氢和硅烷的活性的腐蚀性材料的影响。 此外,在将物品处理和暴露于水分之后,当制品随后用干燥的气态流体冲洗时,与未处理的制品相比,制品呈现出可接受的水分除气速率所需的时间减少。 根据本发明,要被钝化的表面用干燥的气态流体冲洗,与不锈钢化学地不反应并基本上不含氧。 在这种冲洗期间,制品被烘烤和冷却。 烘烤在预定的温度和时间(优选约250.0℃至约500.0℃,约4.0小时)之间完成,以在氧化物层内实现吸附的水分和氢氧化物含量的降低以及铬的增加 内容。 烘烤步骤后,让物品冷却。 这种气体流体可以包括含水量不大于10.0ppb且氧含量约10ppb的氩。 在使用氮气的样品中没有观察到改善。 当氮气没有改善时,应在烘烤过程中用稀有气体冲洗物品,此外还应含有10 ppb以下的氮气。