Research status of ferrite content measurement techniques and standards in stainless steel

Combined with measurement technology, background basis and details of the corresponding standards were discussed and compared respectively. It was pointed out that current special standards of ferrite content were mainly magnetic method, and non-special standards were mainly area proportion method. Influencing factors and existing problems of ferrite content measurement were analyzed, and the practical application requirements included non-destructive inspection, 3D volume proportion measurement and morphological characterization of micro-zone, applicable heat affected zone and cross section of weld pass. Technologies and standards of ferrite content measurement were prospected, it was suggested that accuracy and reliability of ferrite content measurement could be further improved by systematic double-blind experiment and strengthening basic research.