A series of ZnS-rich wurtzite solid solutions containing 8, 12 and 16 mol% Ga2S3 has been prepared. The
influences of the fabrication conditions and microstructure on the mechanical properties were examined. It has been
demonstrated that ZniGa2Si +2,is tougher and harder than pure ZnS due to a solid-solution strengthening effect.
The hardness of the solid solutions increases with increasing concentration of Ga2S3and decreasing grain size, the
grain-size dependence being of the Hall-Petch type. Finer-grained solid solutions with moderate concentrations of
Ga2S3 have the highest fracture toughness. Whereas the hardness increases monotonically with increasing mole
fraction of Ga2S3, the fracture toughness is a maximum at around 12% Ga2S3.