If the desired hardness isn't reached, reheat or adjust the parameters?

I’m assuming this issue is with every part in the process. There are a couple things to check.

First, check the output of the setup, is every part coming out at the correct temperature. Check with an optical pyrometer or an imager. If it is being heated correctly and still not giving the right hardness, then focus your attention on the quench. Is the quench the right consistency? Is it the right mix of say water and polymer? So this is how I’d break down the process. First, see if you have the right temperature, then look for anything else, and if none of these are the right solution, then I’d even look at the raw material coming in. Is it out of spec and not giving you the right hardness?