I believe it was this post? If not I'm curious about it if you remember. The link and discussion here was a fascinating look into another world for me.

https://news.ycombinator.com/item?id=29696120 https://knifesteelnerds.com/2021/03/25/cpm-magnacut/

Steel is almost magic. Stainless steel is beyond magic.

I had a specialization in Chemistry in High School. For some analysis, the fist step is to dissolve everything in boiling Nitric Acid. But stainless steel has Chrome is like a spell of protection, so you must use boiling Hydrochloric Acid instead. I have no idea why. It's just like magic. It may have Nickel, Molybdenum, and other metals, that give it more magical properties.

A few years ago there was a nice post about copying a normal steel alloy for knives to get an equivalent made of stainless steel. You need to reduce the the Carbon content to make it less brittle. And they had to add Vanadium so it keeps the sharpness of the knives. I have no idea why. It's just like magic.

If you have half an hour, it's worth reading, but beware that it has too many technical details that are close to magical https://knifesteelnerds.com/2021/03/25/cpm-magnacut/ (HN discussion https://news.ycombinator.com/item?id=29696120 | 375 points | Dec 2021 | 108 comments)