Can anyone please tell me whether there is any relation between crystal structure and corrosion resistance? I think FCC is more corrosion resistant than BCC. Is it true? Why?
There should be strong correlation between the corrosion resistance (oxidation) in atmospheric environment and the electronegativity for metals and alloys. But I don't see any direct correlation with the lattice structure and the corrosivity since there are many acceptions, which may be realized from the following table of Nobilty:• Graphite HCP, Palladium FCC
Dear Uyime, unfortunately we both made a mistake in misusing the word ' correlation' in the sense of statistics in stead of using The ' Connection' in the sense of mathematics. Yes there is a correlation, which is strong with some exceptions but not connection which doesn' t allow any exception what so ever. Even you can calculate the correlation coefficient by relying on some plausible statistics postulates if you wish!!!I I thank You.
1) The question has already been addressed by Profs. Tarik Ömer Oğurtani and Uyime Donatus. Already you may be knowing about the listing of elements according to their potential differences, i.e., EMF series. Also that corrosion is electro-chemical (i.e., galvanic) in nature. That is to say, having an anodic cell (more oxidized region) and cathodic cell (less oxidized region) with some type of electrolyte (medium) that allows the transport of electrons. Anode and cathode can be different types of metals or it can be different regions of the same metal.
2) Answer to your query:- I have not come across direct relationship between crystal structure and corrosion resistance.
But I have come across that
(a) crystal orientation does affect corrosion [please see (i) book "Fundamentals of Electrochemical Corrosion" By Ele Eugene Stansbury, Robert Angus Buchanan, Chapter 5, page 203, ASM 2000 and (ii) very old paper that I do not have but like to read: "Relations between Crystal Structure and Corrosion", Gerhard Derge, doi: 10.1149/1.3498428 J. Electrochem. Soc. 1939 volume 75, issue 1, 449-462] and
(b) high entropy alloys seems to have better corrosion resistance [please see: (i) Book on "High-Entropy Alloys", B.S. Murty & Jien-Wei Yeh & S. Ranganathan, Elsevier, 2014. (ii) "HIGH ENTROPY ALLOYS AND CORROSION RESISTANCE –A BIRD’S EYE VIEW", S. John Mary et al., Eur. Chem. Bull, .2014, 3(12), 1031-1035. (iii) "Structure and properties of FeCoNiCrCu0.5Alx high-entropy alloy", Bao-yu LI, et al., Trans. Nonferrous Met. Soc. China 23(2013) 735−741].