The Effect of Processing Parameters on the Mechanical Properties of Calcia-Stabilized Zirconia (CSZ) for Dental Use

Abstract

Three different compositions with 9%, 12%, and 15% of calcia-stabilised zirconia (CSZ) were prepared from commercially available submicron-sized powders by cryo-milling. The influence of the sintering conditions, temperature, and dwell time varied as 1400, 1500, and 1600 °C, at durations of 4, 3, and 2 h on mechanical properties is studied. SEM and XRD studies were performed on the pellets obtained by hydraulic pressing in a uniaxial press at 13 tonnes. The effect of sintering holding time and temperature on the mechanical properties, such as hardness, flexural strength, and compressive strength (in a universal testing machine), of CSZ is studied. It is seen that, with the increase in calcia, hardness, flexural strength, and compressive strength increase, until full stabilisation of zirconia is created due to calcium ion substitution in the ionic vacancies. An increase in sintering temperature and time has a positive effect until 1600 °C and 2 h on the flexural and compressive strengths of CSZ. Mechanical properties of CSZ obtained through cryo-milling and sintered at high temperature 1600 °C and shorter holding time is found suitable for dental applications.