... , ≤1×1,0-9 Pam3/s Flatness of copper surface,≤0.005mm Parallelism between copper surfaces,≤0.03mm Concentricity between flange and ... copper,≤0.5mm Pull test,≥5KN/cm2 Temperature cycling,-65°C~ ... Flange,TU1(OFHC·Cu)or Ni42Fe58 Alloy Copper contact,TU1(OFHC·Cu) Solder,Ag72Cu28 Alloy Gate tube,TU1(OFHC·Cu)or Ni42Fe58 ...