| 摘要 |
<p>PURPOSE:To provide a humidity sensor which is excellent in linearity of a resistance - humidity curve, low in the whole resistance value, and reduced in a cost and size by using a ceramic sintered substance having a specified composition. CONSTITUTION:A humidity sensor is formed of a ceramic sintered substance having a composition of SrFe1-xWxO3. when, in a composition formula, X exceeds 0.35, linearity of a resistance - humidity characteristic curve is damaged, and resistance of a whole is increased. Reversely, when X is below 0.1, the gradient of the characteristic curve is low and linearity is also poor. Thus, X is set to a value higher than 0.1 and lower than 0.35, and set preferably to 0.25-0.31. Porosity is set to 7% or more to form a porous substance having a high surface area. A porous ceramics sintered substance so prepared is manufactured in a way that raw material powders of, for example, strontium carbonate, a ferric oxide, and a tungsten oxide are mixed together, and after temporary firing, molding is effected, and a molded product is regularly fired.</p> |
