编辑-地球科学江南体育网页版堆栈交换江南电子竞技平台

你不是登录。你的编辑将被放置在一个队列,直到同行评议。

我们欢迎编辑,使读者更容易理解和更有价值。因为社区成员审查编辑,请尽量使文章更好比你怎么发现,例如,通过修正语法或添加额外的资源和超链接。

钢构件能持续多久?

人为的钢构件能够像化石保存了数百万年,或腐蚀会使他们消失?是什么金属,如铝,不容易腐蚀?

回答

当我们谈论一个化石,我们通常不意味着保存对象,而是一个保留跟踪对象的,喜欢它的印象在其他材料。金属物品肯定会留下印象在周围材料,以及氧化物。所以在这个意义上他们可以很容易地离开化石。钢构件是否其自我持续很久取决于金属的细节,它遇到化学和热条件。但在大多数情况下,活性铁和铝等金属反应了通过多种不同的腐蚀机制上市[这][1]。有一个很好的(表)[2]的腐蚀发展的几个类型的合金钢。这包括Hastalloy,最耐腐蚀形式的钢因此常用于核电站。工业用,“优秀的耐腐蚀”每年不到0.1毫米的腐蚀过程。,通过100米的金属腐蚀速率要吃一百万年。Zinc-steal接触淡水腐蚀的速度至少(10毫米/年)[3],这将迅速摧毁它在大时间尺度。 Another way of looking at it is that basically all iron on Earth is found in the form of iron oxide, so iron compounds do not tend to stay oxidized over large time scales. Similarly, aluminum reacts with oxygen rapidly and is hardly ever (but not never) found in nature as an elemental metal. Some surface treatments such as anodization can extend this time, but will eventually fail. Some elemental metals can be found in nature, which is an indication that under some conditions they could be found as fossils. These "[native metals][4]" particularly include copper, gold, silver and platinum-group metals (see link for a full list). If, however, a reactive metal object is kept well away from oxygen and water it may last much longer. This is the case for satellites, although most satellites orbits are not entirely stable. The longest lasting may be those boosted into [graveyard orbits][5]; standard geosynchronous satellite graveyard orbit results in an expected orbital lifetime of millions of years. Objects on Mars stand a good chance of lasting for long time scales, since they are not exposed to air or water, and are kept cold with little thermal cycling. They are also likely to become buried in dust blown by the Martian wind. The Philae comet lander may be similarly preserved, though comets tend to crash into planets after a few million years. Similarly, several of the outer planet probes may last for extreme time scales since they will be in vacuum, cold, and safe from major collisions. In particular: Voyager 1 & 2, Pioneer 10 & 11, New Horizons. But these are continuously moving away from the solar system, so while preserved, won't leave any fossils to find. In total, the answer appears to be eons, but few objects will find suitable conditions, and the best place to look will be on Mars. [1]: https://tubingchina.com/Corrosion-mechanisms-in-stainless-steel-Tube.htm [2]: https://tubingchina.com/Corrosion-Resistance-Table.htm [3]: https://tubingchina.com/Corrosion-of-Zinc-Coated-Steel-in-Selected-Natural-Fresh-Waters.htm [4]: https://en.wikipedia.org/wiki/Native_metal [5]: https://en.wikipedia.org/wiki/Graveyard_orbit [6]: https://en.wikipedia.org/wiki/List_of_artificial_objects_on_the_Moon

编辑总结

取消

添加一个评论 |

正确的小错误或错误
澄清的意思,而不更改它
添加相关资源或链接
总是尊重作者的意图
不使用编辑与作者回复

创建代码用引号”或式子~篱笆
' ' '
像这样
' ' '
添加语言标识符来突出显示的代码
”“python
def函数(foo):
打印(foo)
' ' '
把段落之间的回报
在结束linebreak添加2个空间
_italic_或* *的* *
报价将>开始的
做链接(尽量使用https)
< https://example.com >
(例子)(https://example.com)
< a href = " https://example.com " > < / >示例
MathJax方程罪\ \ ^ 2θ美元

格式帮助»
回答帮助»

MathJax帮助»