The effect of carbon addition on the mechanical properties and fracture behaviors of cobalt-chromium-iron- manganese-nickel high entropy alloyAuswirkung von Kohlenstoff auf die mechanischen Eigenschaften und das Bruchverhalten von Kobalt-Chrom-Eisen-Mangan-Nickel-Legierungen mit hoher Entropie

The uniaxial tensile and cupping tests of cobalt-chromium-iron-manganese-nickel high entropy alloy were performed to investigate the effect of solid soluted carbon addition on the strengthening mechanism. The results revealed that at 0.5 at % carbon, the tensile strength, uniform elongation, and cupping strength of the sample were promoted. However, the brittleness fracture appeared by further increasing carbon to 1.0 at %, as caused by the carbides along grain boundary. With carbon increasing, carbide precipitation is observed along the grain boundaries, resulting in micro-cracks formation with poor plastic capacity. Meanwhile, the carbon addition significantly improves the tensile and cupping force of the investigated materials, but at 1.0 at % carbon addition deteriorates the plastic capacity.image