Test for Electrical Resistance of Ceramics at Elevated Temperatures

Test for Electrical Resistance of Ceramics at Elevated Temperatures

Insulators in electrical systems support the components mechanically and separate one conductor from another, limiting the flow of electricity to wires or other conducting routes. High-resistance materials are thought to make superior insulators.

In order to measure the electrical resistance of ceramic insulating materials at elevated temperatures between 100 and 500 °C, ASTM D1829 specifies two methods: insulation resistance and volume resistivity. Insulation resistance and volume resistivity can provide the information needed to develop insulating devices for high temperatures as well as reveal contaminants in the insulator. 

For the purpose of designing an insulator for a particular application, volume resistivity is computed from the resistance and dimensional data. According to studies, resistance varies with temperature. When planning for the conditions that the insulator would really be operating in, these changes in resistivity must be taken into account. Volume resistivity is used to examine an insulating material’s uniformity, processing-related uniformity, or to find conductive impurities that lower the material’s quality.