Role of glycine-to-nitrate ratio in influencing the powder characteristics of La(Ca)CrO3

Ultrafine La(Ca)CrO3 (LCC) powders were prepared through glycine-nitrate gel combustion process. The effect of glycine-to-nitrate ratio on batch size, particle size, nature of agglomeration and densification was studied. As-prepared powders when calcined at 700 °C resulted in LCC along with a small amount of CaCrO4. The primary particle size obtained in case of stoichiometric and fuel-rich precursor was found to be 25–60 and 60–180 nm, respectively. It was found that the final powder had softer agglomerates with increasing glycine-to-nitrate ratio, which in turn improved the sintered density. The powder obtained through fuel-rich precursor could be sintered to ≈98% of its theoretical density at 1300 °C without applying any ball milling operation.