Influence of a cryogenic treatment on the fracture toughness of AISI 420 martensitic stainless steel

PRIETO, GERMÁN; TUCKART, WALTER ROBERTO; PÉREZ IPIÑA, JUAN ELÍAS

MATERIALS AND TECHNOLOGY

INST ZA KOVINSKE MATERIALE I IN TEHNOLOGIE

Lugar: Ljubljana; Año: 2017 vol. 4

1580-2949

Cryogenic treatments have been employed over the last three decades in both tool and high-alloy steels to improve their wear resistance, mainly through the transformation of retained austenite and the precipitation of fine carbides. However as the enhancement of a material property is often at the expense of another, it is interesting to evaluate the effect of this type of treatments on the fracture toughness.The objective of the present work was to determine the plane-strain fracture toughness of a cryogenically treated low-carbon AISI 420 martensitic stainless steel, by means of standardized fracture tests, performed in accordance to ASTM E 399 and ASTM E 1820 standards. In this study, it has been experimentally demonstrated that cryogenically treated specimens showed a simultaneous increase in KIC and in hardness of 30% and 5% respectively compared to conventionally treated ones.