As for Ytterbium - since there doesn't seem to be any stainless steel (SS) alloy for sale or even described / designated a code, it was possibly a one off project. Wikipedia [1] refers to it as a dopant when used in stainless steel alloys - but I think manufactures would still want to know if the SS metal they purchased was treated as such. But there's a lot of secret sauce BS in the manufacturing world.
Some things though are just in error. I used to late teens, refer to and spent much time reading an old but rather technical late 50s or 60s inorganic chemistry book - one of the things that stuck with me was where it mentioned Titanium would decompose boiling water into hydrogen and oxygen ... when I finally got my hands on some pure Titanium I found out it wasn't going to do that like I expected.
As for Ytterbium - since there doesn't seem to be any stainless steel (SS) alloy for sale or even described / designated a code, it was possibly a one off project. Wikipedia [1] refers to it as a dopant when used in stainless steel alloys - but I think manufactures would still want to know if the SS metal they purchased was treated as such. But there's a lot of secret sauce BS in the manufacturing world.
Some things though are just in error. I used to late teens, refer to and spent much time reading an old but rather technical late 50s or 60s inorganic chemistry book - one of the things that stuck with me was where it mentioned Titanium would decompose boiling water into hydrogen and oxygen ... when I finally got my hands on some pure Titanium I found out it wasn't going to do that like I expected.
[1] https://en.wikipedia.org/wiki/Ytterbium