摘要 |
A residual stress measuring apparatus for sensing a magnetic state of an object to measure a residual stress of the object comprises a magnetic sensor for sensing a magnetic state of the object to provide its state in the form of current and voltage, an AC power source for feeding an AC power to the magnetic sensor, a wattmeter for multiplying the current and the voltage supplied from the magnetic sensor to provide a variation of a core loss, and a calculator for converting the variation of the core loss into a residual stress of the object. |