Effect of substitutional Strontium on Mechanical Properties of Akermanite Ceramic Prepared by Solid-State Sintering

Abstract Akermanite (Ca2MgSi2O7) has attracted attention in the biomaterial research due to its excellent in vitro and in vivo bioactivity. Mechanical properties such as microhardness and fracture toughness are of great importance for bioactive materials to predict their performance before failure and thus determine the potential biomedical application. In previous work, sintered akermanite prepared by solid-state sintering at 1200°C showed in vitro apatite formation in simulated body fluid (SBF) solution, but having high porosity (more than 20%). In the present study, bulk akermanite bioceramics was fabricated and evaluated the mechanical properties i.e. microhardness and fracture toughness. The akermanite Sr-doped akermanite were synthesised by solid-state sintering at 1225°C for 4 h. Results indicated that the substitution of Sr enhanced the microhardness and fracture toughness which is attributed to the controlled grain size, improved density as well as better sinterability. However, by further increase in amount of dopant beyond 5 mol%, both hardness and fracture toughness decreased due to the larger grain size. akermanite at 1225°C led to a microhardness and fracture toughness of 2.42±0.24 GPa and 1.48±0.03 MPa.m1/2, respectively which makes it a suitable material for non-load bearing application such as, bone filler material.