| 摘要 |
PURPOSE:To provide a positive characteristic thermister material having a small specific resistance at ordinary temperature and giving positive characteris tic thermisters having a high withstand voltage by adding silica, manganese and a specific semi-conductor-forming agent to main components comprising BaTiO3, CaTiO3, SrTiO3 and PbTiO3. CONSTITUTION:A positive characteristic thermister material comprising barium titanate or a solid solution thereof as a main component and containing silica, manganese and a semi-conductor--forming agent is constituted as follows. The main components comprise 30-95mol% of BaTiO3, 3-25mol% of BaTiO3, 3-25mol% of CaTiO3, 1-25mol% of SrTiO3 and 1-30mol% of PbTiO3. The semi- conductor-forming agent comprises a trivalent rare earth element and at least one kind of pentavalent metals of V, Nb and Ta in a rare earth element:metal ratio of 1:1 to 7:3. The silica, the manganese and the semi-conductor-forming agent are added in amounts of 0.01-5mol%, 0.003-0.1mol% and 0.05-0.1mol%. respectively, based on the main component. |
