An apparatus and related method are provided for a manufacturing process including heating of a processed part. A resistance heating assembly applies an electrical current to a work part comprising a sheet of high-tensile steel having a heat-resistant plating to improve formability. A heating control system regulates the electrical current to the work part in order to control the temperature of the work part. A temperature detector detects a temperature of the work part and generates feedback to the heating control system in order to regulate the electrical current. An electrical resistance detector measures an electrical resistance within the work part and generates feedback to the heating control system in order to regulate the electrical current.