14:25 〜 14:50
[14F-SIS8-02] Special Invited: Properties of CoCrFeNi Medium-Entropy Alloy PM Materials with C Addition
キーワード：high entropy alloy, medium entropy alloy, hot isostatic pressing, gas atomized powder, carbon addition
Medium-entropy alloys which are composed of multiple principal elements show both high strength and high ductility. These alloys basically consist of single solid solution phase without hard particles. Therefore, these alloys show low wear resistance. Casted CoCrFeNi materials with C were evaluated in a past paper. These materials showed high wear resistance but significantly low ductility due to coarse eutectic carbides.
In this study, properties of CoCrFeNi alloy PM materials with C (0 to 5.2 at%) were evaluated for the purpose of achieving both high wear resistance and high ductility owing to fine carbide precipitation. The PM materials were produced by consolidating gas atomized powders by HIP followed by hot forging.
Granular Cr-based carbides under 3 microns were observed in all PM materials including C. Wear resistance was improved with increasing C amount. The PM material with 5.2 at% C showed high strength of 950MPa and high elongation of 10.2%.
In this study, properties of CoCrFeNi alloy PM materials with C (0 to 5.2 at%) were evaluated for the purpose of achieving both high wear resistance and high ductility owing to fine carbide precipitation. The PM materials were produced by consolidating gas atomized powders by HIP followed by hot forging.
Granular Cr-based carbides under 3 microns were observed in all PM materials including C. Wear resistance was improved with increasing C amount. The PM material with 5.2 at% C showed high strength of 950MPa and high elongation of 10.2%.