Effect of tungsten on the microstructure evolution and mechanical properties of yttrium modified HP40Nb alloy

► W facilitates the formation of Cr23C6 during the solidification of HP40 alloy. ► W addition inhibits the precipitation of secondary carbide during aging. ► “Necklace like” chromium carbide is first been observed during NbC transformation. ► By inhibiting the G phase transformation, it restrains the tensile strength declining of alloy.