Microhardness and fracture mechanics of flux grown samarium doped gadolinium vanadate (Sm:GdVO4) single crystal

Indentation induced hardness studies on flux grown samarium doped gadolinium vanadate (Sm:GdVO4) crystals are reported. Mechanical characteristics including Vickers microhardness, fracture mechanics, crack propagation, brittleness index and yield strength are assessed. The mechanical behaviour of the crystal is explained using various theoretical models viz., Meyer’s law, proportional specimen resistance (PSR) and Hays and Kendall’s approach. Variation of microhardness with load is found to be non-linear and is best explained by the concept of Newtonian resistance pressure as proposed by Hays and Kendall’s law. Classification of cracks as median type is explained. The values of fracture toughness (Kc), brittleness index (Bi) and yield strength (σy) have also been calculated.