2004 Volume 45 Issue 12 Pages 3282-3285
Directionally solidified NbSi2/Nb5Si3 in-situ composites have been prepared. Scanning Electron Microscopes (SEM) and X-ray diffraction (XRD) have been used to investigate phase constitution and microstructure. It was found that microstructure and phase stability of directionally solidified alloys depended on growth rate, heat-treatment and alloying element. Compression strength was tested in the temperature range from 1473 to 1773 K and compression axes parallel to growth direction was chosen. High-temperature strength of NbSi2/Nb5Si3 composites increased from 222.9 to 593.77 MPa at 1773 K due to Mo addition.