I am looking for a direct comparison between the corrosion resistance of black zinc vs. ferritic nitrocarburizing. I can't find anything relating to QPQ that will give hours to white or red rust. I have some info that shows black zinc without a sealer at 72 hours to white rust.
The primary function of the 52100 in this application is not wear resistance and the zinc will not be asked to be a wear surface either. It is only for corrosion protection. The 52100 was used simply because it is a standard material for the application and won't affect the product function.
TVP, Thank you for the links. The dekalbmetal.com article on Zn-Ni was especially helpful.
You are correct; I am talking about hydrogen embrittlement during the usage phase. I have specified in the past that parts which have been electroplated are to be baked at 190 C for at least 3 hours...
What corrosion protection process would be best to eliminate the possibility of hydrogen embrittlement in 52100 bearing steel? Is zinc nickel a possiblity?
I have a question about the potential for crack propagation in both .080 and .063 sheet. We currently laser cut and turret punch shapes into these sheets. All things being equal, I am wondering if either method has some inherent advantages/disadvantages as far as the tendency to start fatigue...
TVP,
Thank you for your input. I have been doing some other research and that info is consistent with what I've discovered. Again, thanks for the help; much appreciated. Anything else you can think of is welcome.
Thank you for your input. I have talked to the heat treater and am sending parts for evaluation. His suggestion was the it was probably material related because the QPQ process wouldn't produce a brittle part with only a case depth of .0003-.0008; the part is .104 thick. His other thought was...
I have a part that is stamped from 12 gauge 715 HSLA, grade 50 steel. It is then heat treated (QPQ). Occasionally when I inspect the parts they are ductile when bent and other times they are fairly brittle. Is this a material issue or does this have something to do with the heat treat...
