Metal Oxide Varistor: Zinc Oxide, 0.5 % Bismuth Oxide, 2.5 % Manganese Dioxide, 1350 °C (Masuyama 1972, Ex. 2)

Masuyama, Matsuoka and Nishi found that adding a second oxide to zinc oxide and bismuth oxide changes the varistor a great deal. This is their Example 2 with manganese dioxide: 97 % zinc oxide, 0.5 % bismuth oxide and 2.5 % manganese dioxide by moles, sintered at 1350 °C. The disc measured a C-value of 140 at 1 mA and a nonlinearity exponent n of 4.3. Source: T. Masuyama, M. Matsuoka and T. Nishi (Matsushita), US 3,663,458 (1972), Example 2. Unknown: how the aluminium is sprayed on and what the silver paint is. The 10 g batch is our arithmetic. Picture: the patent's drawing.