Electrical resistivity studies in low carbon and HSLA-100 steels

An electrical resistivity technique has been employed to provide an insight into the phase transformations occurring in a plain low carbon and in a copper bearing high strength low alloy (HSLA) steel. It has been established that the phase transformation temperatures can be accurately estimated when there is a simultaneous magnetic transition. Thus, the Curie temperature of the HSLA steel was observed to be 690degreesC as against 730degreesC for the plain carbon steel. Furthermore, B-s (550degreesC) and B-f (similar to390degreesC) (start and finish temperatures for bainite) were determined using continuous resistivity data. In the HSLA steel, the amount of copper precipitation could be estimated during heating from the quenched condition, the value of which matched well with those derived from isothermal resistivity experiments reported elsewhere.