engleski

Effect of deep cryogenic treatment on dilatometric curve and tribological properties of high speed steel

Advantages of deep cryogenic treatment (DCT) over the standard heat treatment of high speed steels for the purpose of obtaining better properties are quoted in an increasing number of scientific papers to be found in literature. This paper deals with the improvements in high speed steel properties achieved by using DCT on test samples made of PM S390 MC high speed steel. The effect of DCT on the dilatometric curve during tempering and on the abrasive and the erosion wear resistance has been investigated and compared with results obtained from a set of test samples made of the same steel heat treated by the conventional method (hardened and three times high temperature tempered). Dilatometric tests confirmed the existence of common processes in tempering, which depend on the initial state of steel (only quenched, and quenched and deep cryogenically treated). These tests showed that the DCT had not completely eliminated the residual austenite, particularly in the case of the highest austenisation temperature. The tribological results obtained confirm that the application of DCT results in significantly improved erosive wear resistance, while the abrasive wear resistance depends on the temperature of austenisation used.

High speed steel; PM S390 MC; Deep cryogenic treatment; Dilatometric test; Erosion; Abrasion; Wear resistance

Rad je kao predavanje prezentiran na skupu The 19th International IFHTSE Congress, održanom od 17-20.10.2011., Glasgow, Škotska ; uz međunarodnu recenziju objavljen je u Zborniku, CD, 6 str.