Mechanical Properties of Solid‐State‐Synthesized Strontium‐ and Magnesium‐Doped Lanthanum Gallate

This paper has examined the room‐temperature mechanical properties of La 0.8 Sr 0.2 Ga 1− x Mg x O 3−δ ( x = 0.1–0.2) that was synthesized by using a solid‐state technique. The modulus of rupture (MOR) was measured over the range of x = 0.1–0.2 and decreased as the B‐site dopant content increased. At x = 0.15, for example, the MOR was 139 ± 17 MPa, whereas at x = 0.2, an MOR value of 113 ± 8 MPa was observed. This decrease is postulated as being caused by the increased lattice stress due to the increased magnesium concentration on the B‐site. The fracture toughness of the sample decreased as the magnesium content increased; at x = 0.15, a fracture toughness of 1.63 ± 0.2 MPam 1/2 was observed, whereas at x = 0.2, a value of 1.28 MPam 1/2 was obtained.