Material in, metal out

Researchers from Calcutta have managed to develop a new ceramic that boasts of properties which could ultimately mean the replacement of conventional metallic parts used in refractories and engines.

The material which is called 'sialon' ceramic', has been developed by a team of scientists led by Siddartha Bandopadhyay from the Calcutta-based Central Glass and Ceramics Research Institute using - such as clay - as the starting material and a novel sintering technique.

The researchers claim that the sialon ceramic has superior mechanical, chemical and thermal properties when compared with the conventional materials. It can actually replace the conventional metallic parts found in gas turbines and internal combustion engines. If used in wear-resistant materials, it is likely to improve afficiency.

The scientists began by using different compositions of the starting materials - aluminium and silicon nitrides and aluminium oxide - to prepare different phases with varying degrees of hardness. The material was prepared using a new sintering technique that consolidated the starting material from their initial powder state to a dense form.

Bandopadhyay says the sintering was done under vapour conditions, without using any external sintering tool. The discovery of this new material has won for Bandopadhyay this year's Young Scientist Award under the aegis of the Council of Scientific and Industrial Research.