Neutron diffraction studies of Ti3Si0.9Al0.1C2 compound

An aluminum doped titanium silicon carbide with a composition of Ti3Si0.9Al0.1C2 was studied by neutron powder diffraction in comparison with the standard Ti3SiC2 and Ti3AlC2 compounds. The refinements of the diffraction data revealed the included impurity phases and the detailed structural information of these compounds. The analysis confirmed that the impurity phase TiC in Ti3SiC2 could be eliminated by the substitution of Si with a small amount of Al dopant, forming a solid solution of Ti3(Si1−xAlx)C2, with a unit cell slightly larger than that of Ti3SiC2, but smaller than that of Ti3AlC2. However, compared with the anisotropic structure change in Ti3AlC2, the structure change in Ti3Si0.9Al0.1C2 is basically isotropic, which is consistent with the structural optimization of the first principles calculation.