Papers by Author: Willy C.K. Tan

Abstract: Over the years, Sol-gel has been widely used in aerospace industry for surface treatment process in preparation of adhesive bonded repair to aircraft. It plays a crucial role in the process of bonded repair of aircraft as a chemical linkage between adhesive bonded repair and damaged metallic structure of aircraft. As a chemical linkage, it produces strong and durable bond between metal and organic adhesive (Thermoplastics) which improves the overall strength in adhesive bonded repair to aircraft. In this paper, both conventional and newly formulated sol-gel will be subjected under Wedge Test (ASTM D 3762-03) to examine its durability. This would be a crucial milestone if the durability of the newly formulated sol-gel is higher than conventional sol-gel. Cost of repair would be able to reduce as serviceability of the aircraft increase. Keywords: Sol Gel, Chemical linkage, Bonding Strength, Shear strength

Abstract: Fabric materials can be in form of woven, knitted, non-woven and braided structures or a combination of these structures can be used for protective fabric. Properties of fabrics depend on the different types of fibres that constitute the fabric and the geometry of the final structure. This project seeks the development of optimally woven enhanced silk fabric for high performance application that can be potentially beneficial to various engineering fields such as ballistic protection for military, aerospace, automotive, sports and marine engineering industries. Natural enhanced silk will be used as the yarns, rather than the traditionally used synthetically produced aramid material which poses an environmental problem. The tensile strength, tensile modulus and elongation of yarns strength are the main influences on ballistic performance. In addition to the tensile properties of the yarn, fabric weave structure is crucial as propagation of stress waves is affected by the weave structure. Mechanical performance of the woven silk fabric of various designs will be subsequently accessed for their effectiveness based on tensile testing and ballistic testing.

Abstract: When one cut himself, it's amazing to watch how quickly the body acts to mend the wound. Immediately, the body works to pull the skin around the cut back together. The concept of repair by bleeding of enclosed functional agents serves as the biomimetric inspiration of synthetic self repair systems. Such synthetic self repair systems are based on advancement in polymeric materials; the process of human thrombosis is the inspiration for the application of self healing fibres within the composite materials. Preliminary results based on flexural 3 point bend test on prepared samples have shown the healed hollow fibre laminate has a healed strength increase of 47.6% compared to the damaged baseline laminate. These results gave us confidence that there is a great potential to adopt such self healing mechanism on actual composite parts like in aircraft’s composite structures.