Authors:
Miroslav Karlík (CTU Prague, Czech Republic)
Hana Thürlova (University of Chemistry and Technology, Czech Republic)
Filip Průša (University of Chemistry and Technology, Czech Republic)
Jaroslav Cech (CTU Prague, Czech Republic)
Petr Hausild (CTU Prague, Czech Republic)
Abstract:
CoCrFeNiMn alloy in equiatomic composition was prepared from pure metals by powder metallurgy, and the reinforcing carbides were formed in situ after adding 1 wt.% of two precursors – machined graphite (C) and plasma-gasified carbon (PG). The powder was either mixed with the precursors, or 30 min. of mechanical alloying (MA) in a planetary ball mill was carried out. The microstructure, phase composition, and mechanical properties of spark plasma sintered (SPS) compacts were studied. During sintering, the matrix remained as an FCC phase while Cr23C6 carbides, which formed throughout MA, transformed to Cr7C3. The best mechanical properties were achieved for the PG-reinforced alloy after 30 min of MA. This material reached a compressive yield strength (CYS) of 1237 ± 50 MPa and ultimate compressive strength (UCS) of 1998 ± 46 MPa, together with ductility of 25%. The MA+SPS reference alloy compacts without carbide reinforcement had CYS of 988 ± 14 MPa; the UCS was not measured because of the very high plasticity of the alloy (no fracture occurred).
DOI:
https://doi.org/10.59499/EP256764300
