The isothermal diagram of transformation of the residual austenite by tempering
- Academy of Science of the Ukraine, Kiev (Ukraine). Inst. of Casting Problems
The residual austenite forming in the case-hardened layer has a strong influence on the resistance of the surface of steels to destruction under the effect of large contact stress. To make the austenite retained in the structure of carburized steel decompose, intermediate tempering at 600 C to 650 C for several hours is sometimes undertaken. Since the literature contains practically no quantitative data on the disintegration of residual austenite in carburized steels, the conditions of high tempering are chosen empirically. Sometimes the disintegrations of residual austenite in tempering are explained by using isothermal diagrams of supercooled austenite. However, this is incorrect because the processes occurring in steels during isothermal holding after cooling from quenching temperature do not express the processes occurring during tempering. If these processes are to be evaluated correctly, it is necessary to plot specific isothermal and thermokinetic diagrams of the transformations occurring during the tempering of hardened steel. An investigation was conducted to study the disintegration of residual austenite in the case-hardened layer of complex-alloyed carburized Cr-Mn-Ni-Mo-V steel with 0.18 pct carbon content during tempering.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 142329
- Journal Information:
- Metallurgical Transactions, A, Journal Name: Metallurgical Transactions, A Journal Issue: 12 Vol. 24A; ISSN 0360-2133; ISSN MTTABN
- Country of Publication:
- United States
- Language:
- English
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