Nanometric zirconia-mullite precursors are synthesized through sol-gel route. Incorporation of these precursors in low cement castable refractories improves the bulk density, compressive strength and thermal shock resistance through formation of integrated matrix of castable at high temperature. In the present investigation, white tabular alumina aggregate, calcium aluminate cement bond material, microsilica, microfine alumina and nanometric zirconia-mullite precursors are used in the formulation. The important properties like bulk density, apparent porosity, linear change, cold crushing strength before and after thermal spalling of castables are studied. Phases are identified by X-ray diffraction analysis. SEM study has been used to analyze the integrated matrix of the castables. © 2010 Taylor and Francis Group, LLC.

N ACHARJEE

P K D PODDAR

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Effect of nanometric zirconia-mullite precursor on the properties of low cement castables

Transactions of the Indian Ceramic Society

Activated alumina is prepared by thermal dehydration (300°-600°C) of chemically pure aluminium hydroxide. The prepared materials have been characterized by residual water content, BET surface area and hydraulic activity. These aluminas are incorporated in cement free castable batch. Important properties like bulk density, apparent porosity, linear change, cold compressive strength, strength retainment after thermal shock have been studied. X-ray diffraction analysis has been performed to identify the phases formed while SEM studies have been used to get an idea about the microstructure of the castable matrix. © 2009 Taylor and Francis Group, LLC.

Development of activated alumina and its effect on the properties of cement free castables refractories

A nanocrystalline powder of 5 mol% yttria stabilized zirconia (YSZ) is prepared by polymeric precursor routes. Three different routes, viz. (i) amorphous citrate process, (ii) Pechini process and (iii) polyethylene glycol (PEG) assisted process are examined. In these processes, parameters such as metal cations to fuel ratio or components of fuel are varied and the effects analyzed. A novel experimental procedure for controlled combustion based on the thermal analysis has been adopted. All the three processes yield nanocrystalline powders with average crystallite size lying in the range of 9 to 18 nm. Densities as high as 99% of theoretical density (TD) could be achieved by sintering the compacts of powders at a relatively low temperature of 1400°C for 2 h. © 2005 Taylor and Francis Group, LLC.

Journal	Transactions of the Indian Ceramic Society
Publisher	INDIAN CERAMIC SOC
ISSN	0371-750X