No abstract

Compacts formed from high-purity fused submicrometer mullite powders, both pure and with the additions of 5 to 25 vol% Zr02 of particle size 1, 2, or 4 pm (average), were sintered in air at 1610°C for 6 h to form dense ceramic bodies. Mechanical properties (flexural strength, KIc, and Young's modulus) were measured both before and after thermal shock. The strength after thermal shock increased considerably in systems containing additions of 10 to 20 vol% ZrO,; K,, also increased, but not so markedly. The low fraction of tetragonal ZrOz (0.1 to 0.2) in the as-fired samples and the increase in Young's modulus after thermal shock for some strengthened samples supported the view that the interaction of residual internal stresses induced by quenching and the accompanying martensitic transformation of ZrOz result in potential nucleation sites for microcracking. Thus, microcracking may be the predominant energy-absorbing mechanism responsible for strengthening and toughening the quenched ceramic bodies.

The popularity of retirement villages in many developed countries provides a potential market in Malaysia, which is rapidly facing an ageing society. However, little is known about the purpose-built retirement neighbourhood especially its desirability among the local elderly and niche in smaller towns which are poised to reap economic benefits from their locational advantage trending the retirement industry in the region. This study aims to firstly, explore the desirability of retirement neighbourhood among the Chinese elderly in Segamat using semistructured interviews and secondly, identify the niche market of such neighbourhood and its potential contribution to support development strategy of the town. The preference for retirement neighbourhood as an alternative living arrangement among the Chinese elderly in Segamat indicates its good potential as a new source of economic growth but requires that public planning facilitates efficient land development process and increase amenity and services for all especially the elderly.