Effect of retained austenite on the fracture toughness of tempered tool steel

• Autorzy: Kokosza A. , Pacyna J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: This paper is an attempt of reviewing the outlooks about the favourable influence of retained austenite on fracture toughness of tool steels according to results of investigation concerning relations between tempering temperature, hardness, fraction of retained austenite and fracture toughness. Design/methodology/approach: The tests were performed on the samples made of the 70MnCrMoV9-2-4-2 steel in which the fraction of retained austenite was changed by cold treatment and by changing the tempering temperature. On the ground of analysis of dependencies between fraction of retained austenite, hardness, fracture toughness and tempering temperature of hardened 70MnCrMoV9-2-4-2 steel the influence of retained austenite on fracture toughness of tested steel was investigated. Findings: was found that retained austenite remaining in the structure of tested steel after quenching increased its fracture toughness on directly proportional way to its volume fraction. Advantageous influence of this phase was also found after tempering tested steel. Research limitations/implications: It was pointed out that most beneficial influence of retained austenite exists when tested steel after hardening is low-tempered. At that moment the highest stabilization of the phase occurs. While at tempering temperatures above 220°C it was indicated that it is possible to combine retained austenite transition and irreversible tempering brittleness. Originality/value: On the basis of own research, the authors present their own, original point of view on the issue of presence of retained austenite in the structure, its stability and the influence on fracture toughness of lowtempered tools steel.

Słowa kluczowe

EN

tool materials; fracture toughness; retained austenite

PL

materiały narzędziowe; odporność na pękanie; austenit szczątkowy

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2008
• Tom: Vol. 31, nr 2
• Strony: 87--90
• Opis fizyczny: Bibliogr. 17poz.

Twórcy

autor

Kokosza A.

autor

Pacyna J.

• Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, ul. Mickiewicza 30, 30-059 Kraków, Poland,

Bibliografia

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