I tried to do the same with a piece of a large broken saw blade that required carbide tips to cut.
The steel in the main blade was at mid 40s Rc before and after H.T.

You need to start with a blade that does not use hardened tips.
I acquired a very old 26" mill blade that was made with one uniform steel including tips.
Besides original hardening of the whole blade, it had also some age and work harding.
It makes a pretty good blade.

In my experience anyhow.

Last edited by michiganroadkill; 05/14/20.
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