Structure of Scale on Plain Carbon Steels

摘要: THE classical picture of high-temperature scales on plain carbon steels as determined by Pfeil1 shows a three-layered structure. An outer layer haematite, Fe2O3, middle one magnetite, Fe3O4, and an inner wustite, FeO, next to the parent metal is normal composition this layered structure in scale that continuous with metal. (For practical historical reasons, wustite normally given stoichiometric FeO when fact it more accurately described Fe1−yO, where Y concentration vacancies.) Similarly, Paidassi2, his recent work kinetics oxidation pure irons between 700° 1,250° C., found present scales. However, 15 min. was minimim oxidizing time for lower-temperature he reported.