Microstructural evolution and mechanical properties of an Nb-16Si in-situ composite with Fe additions prepared by arc-melting

► Nb-16Si-xFe ternary in-situ composites (x = 2, 4, 6 at.%) were prepared. ► With Fe additions Nb4FeSi silicide forms besides NbSS and Nb3Si phases. ► Fe is an element that suppresses formation of the Nb3Si phase. ► The Nb4FeSi is brittle, its KIC and E are about 1.22 MPa m1/2, and 310 GPa. ► At 1250 °C and 1350 °C, strength of the Nb-16Si alloy is decreased with Fe.