Fabrication of tougher ZTA ceramics with sustainable high hardness through (RSM) optimisation

The requirement of attainment hard and simultaneously tough materials is a crucial matter for industrial sectors. However, the toughness and hardness are mutually exclusive. Enhancing one result in the other being sacrificed. Hence, the strategy of compromise between formations of elongated CaAl12O19 grains with minimum porosity inside ZTA is implemented to overcome this challenge. To accomplish this target, the Design of Experiment (DOE) is employed through Response Surface methodology (RSM) involving Central Composite Design (CCD) to optimise three variables of combination addition between CaO and CaCO3, sintering temperature and soaking time. The optimised variables resulted to accomplish the optimum responses of the indentation fracture resistance and hardness of ZTA ceramics. Empirical models are found for responses and their quality are checked using Analysis of Variance (ANOVA) and other parameters. The results show that the sintering temperature is the most influential variable on the responses while combination addition between CaO and CaCO3 is significant in improvement of mechanical properties.