The approach is to build a high voltage insulator consisting of two materials:  Poly-Ether-Ether-Ketone (“PEEK”) and Machinable Ceramic (“MACOR”).  PEEK has a high stress tolerance but cannot withstand high temperatures, while MACOR has high heat tolerance but is difficult to machine and can be brittle.  MACOR is used for the plasma-facing surface, while PEEK will handle the…