PT  - JOURNAL ARTICLE
AU  - Jurči, Peter
AU  - Kusý, Martin
AU  - Ptačinová, Jana
AU  - Kuracina, Vladimír
AU  - Priknerová, Petra
TI  - Long-term Sub-zero Treatment of P/M Vanadis 6 Ledeburitic Tool Steel - a Preliminary Study
DP  - 2015 Feb 1
TA  - Manufacturing Technology Journal
PG  - 41--47
VI  - 15
IP  - 1
AID - 10.21062/ujep/x.2015/a/1213-2489/MT/15/1/41
IS  - 12132489
AB  - The microstructure, the phase constitution and the tempering charts of Cr-V ledeburitic steel Vanadis 6 subjected to sub-zero treatment with various soaking times in liquid nitrogen have been investigated. The microstructures have been characterized using the light microscopy, scanning electron microscopy and X-ray diffraction. The hardness has been evaluated by Vickers method. The matrix is martensitic with certain amount of retained austenite, irrespectively to the time of sub-zero treatment. The amount of retained austenite, however, decreases up to the soaking time of 17 h and then remains almost constant. The microstructure of sub-zero treated steel contains enhanced portion of small globular carbides, as compared to conventionally heat treated material. These particles have a size of around 100 nm in most cases. The as-quenched hardness manifests a moderate increase due to the sub-zero treatment. The hardness decreases during subsequent tempering and this decrease is more pronounced in sub-zero treated samples.