An overview on manufacturing and properties of syntactic foams made of ceramic hollow microspheres and starch

Abstract

Manufacturing and properties of novel syntactic foams made of ceramic hollow microspheres and starch are overviewed. Various parameters in relation to two different manufacturing processes are discussed. Theoretical relations based on a statistical model for pre-mould processing are presented. The relations are compared with experimental/numerical data for various microspheres and shown to be capable of predicting effects of microsphere size on volume expansion rate under various conditions arising from starch content in binder and initial bulk volume of microspheres. A two-step manufacturing process viz. moulding and forming is suggested for syntactic foam dimensional control. Compressive and flexural failure behaviours of the manufactured foams are also reviewed. Some conditions of relativity arising from properties of constituents leading to the rule of mixtures relations for compressive strength and to understanding of compressive/transitional failure behaviour are presented. Hygroscopic behaviour of syntactic foam panels is discussed.