漫话合金钢2

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看资料特别是实验为基础的学科，例如材料，这玩意没有严格的数学公式推导，多数情况下
只能通过不断的实验对比得出结果，找出一个比较优化的解。国人在写这些资料时由于没有
数学和方程的“束缚”又没耐心做实验，读者又不能立刻鉴”真伪“，国内资料绝大多数都是TM
东拼西凑，强行抄袭他人的片断，读起来感觉像绕弯弯，甚至作者自己都不懂这些东西。
读鸟语稍微好一些但是有些也含糊其词，怎么办只能读很多家的东西，然后对比。再去找
相应的材料规范，对比这些说辞，就能确定那些靠谱哪些纯粹是为了”添头“。
说回N,H,O。H和O好说，因为这两个家伙基本都是有害的在钢中。H是最小的原子的元素，因为
体积小所有很用躲进”缝隙中"。
这哥们有个什么特点呢就是液体钢中溶解度大，固体中溶解度小。一旦凝固被锁住后，氢原子会
想法设法逃出来，在钢中常成游离态，假如条件合适结合成氢气了，造成局部很高的应力最
后结果就是氢脆和白点。
O很容易和其他元素形成氧化物，氧化物和磷化物有点像都是脆性的和基体本身的结合性不好，在
受力后，结合处很容易成为薄弱点导致裂纹的萌生，被钻了空子。
所有以在转炉和钢包中脱气就是必须的，脱的越干净钢的性能和等级就越高，相应的成本就会上升
在质量允许的情况，合适即可。
说回N，优点挺多比如表面渗氮，以合金钢为主，在表面和合金元素形成氮铁某物，一个是硬度高耐磨
二来这些氮化物耐腐蚀，其次由于强行“塞入"N，导致表面形成压应力，可以提高疲劳强化。
含量2%以下时，有些场合可以顶替C到达同样的作用并且材料均匀性和韧性更胜一筹，瑞典人玩钢铁
真是一绝，听过巴斯钢嘛，就是以N为主强化的钢远胜过马氏体不锈钢，瑞典人已经玩出了含N量为3%
完全取代C的氮钢。
虽然这么优点，但是多数情况只能当杂质脱去，因为不好玩属于高科技。

rusher

求教：液态和固态溶解率不同，是什么原因？分子间隙不同？溶解率指的是分子还是原子？

rusher

https://en.wikipedia.org/wiki/Hydrogen_embrittlement  - wikipedia的解释我看了下，还行。要想深入了解，网址的下方有参考目录。看他个四五篇就行。最好用这个关键词查下新的论文数据库，比如ASME或者sciencedirect；最新的论文里Literature review，看了就大差不差了。需要深入，再按照脉络重新走一遍。

以上是世界通用的，经过学术训练的必备技能，在此推荐一下。

原文链接：https://www.imetllc.com/training ... mbrittlement-steel/

Abstract: This article discusses hydrogen embrittlement of carbon steel.  This includes a discussion of the mechanism by which a steel becomes embrittled by hydrgogen, circumstances that lead to embrittlement, the effects of embrittlement on steel behavior, how to prevent the embrittlement, and tests for evaluating whether a steel has been embrittled.

Hydrogen embrittlement is a metal’s loss of ductility and reduction of load bearing capability due to the absorption of hydrogen atoms or molecules by the metal.  The result of hydrogen embrittlement is that components crack and fracture at stresses less than the yield strength of the metal.

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Embrittlement process
At room temperature, hydrogen atoms can be absorbed by carbon steel alloys.  The absorbed hydrogen may be present either as atomic or molecular form.  Given enough time, the hydrogen diffuses to the metal grain boundaries and forms bubbles at the metal grain boundaries. These bubbles exert pressure on the metal grains. The pressure can increase to levels where the metal has reduced ductility and strength.

Hydrogen embrittlement
Situations leading to hydrogen absorption

Hydrogen can enter and diffuse through steel even at room temperature.  This can occur during various manufacturing and assembly operations or operational use – anywhere that the metal comes into contact with atomic or molecular hydrogen

Processes for which there is a possibility of absorption of hydrogen include acid pickling and electroplating.  Hydrogen is present in acid pickling baths.  During electroplating, hydrogen is produced at the surface of the metal being coated.  Acid pickling is used to remove oxide scale from the surface of steel and electroplating is commonly used to deposit zinc on steel nuts, bolts, screws and other fasteners for galvanic corrosion protection of the steel.  Other electroplated coatings are used for different applications.

Hydrogen absorption can also occur when a component is in service if the steel is exposed to acids or if corrosion of the steel occurs.