Carbon Distribution and the Influence on the Tempering Behaviour in a Hot-Work Tool Steel Aisi H11

Abstract:

The microstructure of the common hot-work tool steel AISI H11 has been characterized by atom probe tomography with the focus on the carbon distribution after the hardening treatment and in the early stages of tempering. The carbon distribution shows significant differences within the probed volumes, regions differently affected by carbon segregation can be observed in some specimens. In all samples pronounced carbon segregation to dislocations and cluster formation is observed. Through all hardened samples no segregation of any substitutional elements has taken place. Heating to 500°C does not significantly change the elemental distribution. Carbon enriched interlath austenite films with peak carbon levels of 6 to 9 at% show a thickness increase with increasing λ. These films and the pre-existing carbon clusters have been found to be nucleation sites for carbide formation during heating to 610°C.

• Periodical: Advanced Materials Research (Volume 409)
• Pages: 702-706
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.409.702
• Online since: November 2011
• Authors: Christoph Lerchbacher, Silvia Zinner, Harald Leitner
• Keywords: Atom Probe, Carbon Segregation, Hot-Work Tool Steel, Martensite, Retained Austenite

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