I reconfigured my 4″ batch rocket stove oven so that I had a mini pizza oven. I can’t find my tile cutter at present so I just used a 30 cm square terracotta (unglazed) tile and placed it in the middle of the flame stream. The tile only cost me NZD5.
It’s a dead end oven on the left, flames come in on the right, and the top is insulated by the cast iron plate to provide steady heat. The main flame path passes underneath the tile and to the chimney.
There was a loud crack before the tile even reached 120 deg C, and I think that’s because the tile was too big. I needed to cut it so that it was mainly in the oven and not exposed to the outside causing too much differential temperature stress. These tiles are baked at 1200 deg C.
But the outcome for the pizza was a success with a crispy base.