EFFECT OF PURITY ON MICROFRACTOGRAPHS OF STRUCTURAL STEEL

We used the e lectron microf rae tograph ic method to determine the effect of purity on the ductite and bri t t le f rac ture of improved s t ruc tura l steel 40KhN2 (Table 1). We compared standard steel, pure steel, and high-puri ty steel. The standard steel was melted f rom Armco iron in an open induction furnace. The pure and high-pur i ty steels were produced by vacuum arc remelt ing of cast e lectrodes that were melted in a vacuum induction furnace. The charge ma te r i a l s were Armco iron for the pure steel and carbonyl i ron for the high-puri ty steel.