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bosox
10-08-2012, 04:15 PM
I would like to ask some help from you guys. Why same chemistry steel from different supplies of hot band , after it cold reduction with Q&T behaves differently , at times lead higher corrosion - any insight to this problem ( 75Ni8, 76Cr1 steel ). Any information will be much appreciated. Thanks.

boslab
10-08-2012, 08:09 PM
the clue is the cold reduction all be it there may well be a greater dissolved 02 in many brands, inadequate dexidation at the steelmaking stage leads to accelerated corrosion and dissolved 02 should be kept as low as possible say <500 ppm, many are way above several thousand ppm, cheaper to make as you need less deoxident, usually Al is used but Ti and calcium are also used, if you have a high 02 and add cold reduction then the steel is already at a corrosion disadvantage [but it is cheaper to make]
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