Posted on 05/04/2002 9:02:32 PM PDT by PeaceBeWithYou
In these cases, hydrogen was a byproduct of the anti-corrosion coating(zinc) reacting with the coated metal. once the coating is cracked it becomes a zinc-iron battery, and weakens the iron electro-chemically.
I.E. Cracking due to hydrogen embrittlement of steel under stress occurs when atomic hydrogen diffuses through the metal lattice, where they recombine to hydrogen molecules producing an internal pressure in the metal. Absorption of atomic hydrogen by the prestressing steel usually occurs by cathodic charges, which develop in a corrosive environment when steel is electrically coupled to more anodic metal, e.g., zinc coating.
The atomic hydrogen may be formed by the corrosion process itself or as a result of some manufacturing operations, e.g., pickling or welding.
Cracking of the steel can either be a direct consequence of the tensile stresses developed by the hydrogen molecules within the metal lattice during their formation from two hydrogen atoms or in combination with tensile stresses. It should be mentioned that different steel types are differently susceptible to hydrogen embrittlement.
There is now a zinc coating process that overcomes this, and it involves (oddly enough) fusing iron to the zinc coating and heat bonding it to the steel to be protected, but there are prolly still quite a few 90-96 autos out there that missed the recalls.
Stay safe.
A fairly simple chemical process joins borax and hydrogen in a manner that renders the gas nonflammable.NOT A SOURCE OF HYDROGEN, but perhaps a practical way to store it. The proposed spent fuel exchange system is analogous to the electrolyte exchange system proposed 35 years ago or more for the upcoming battery powered auto fleet we were soon to have. :') Adding the hydrogen back in could be done at night, using off-peak capacity.
I don't know which is true but if it is the first then the hydrogen has to come from somewhere to be added to the Borax.
From the article above:
When mixed with water in the Natrium's fuel system, this sodium borohydride powder produces free hydrogen for the fuel cell
I hope you made a lot of money investing in this technology over the last 4 years. I invested in coal to liquid and am doing OK.
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