Abstract
The effect of temperature on the impedance of painted steel panels in sodium chloride solution was investigated.
When paint films were not deteriorated temperature coefficients of resistance were large, but the ones of deteriorated panels were small.
Capacitance of painted steel panels was not seriously affected by temperature.
Frequency characteristics of resistance of undeteriorated panels at high temperature were different from the ones at low temperature, but the ones of deteriorated panels were not.
The abnormal phenomenon that the resistance decreased at low temperature was observed on some panels. Hair cracks were observed by the microscope on the paint films of these panels. The width of the hair crack is considered to have increased at low temperature because thermal expansion of the paint films is larger than the one of the steel panels.
