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Dr. Kwek-Tze Tan

Impact behavior

Articles 1 - 3 of 3

Full-Text Articles in Mechanical Engineering

Understanding Effectiveness Of Stitching In Suppression Of Impact Damage: An Empirical Delamination Reduction Trend For Stitched Composites, Kwek Tan, N. Watanabe, Y. Iwahori, T. Ishikawa Apr 2015

Understanding Effectiveness Of Stitching In Suppression Of Impact Damage: An Empirical Delamination Reduction Trend For Stitched Composites, Kwek Tan, N. Watanabe, Y. Iwahori, T. Ishikawa

Dr. Kwek-Tze Tan

In this paper, a novel empirical trend has been identified to understand the delamination reduction in stitched composites subjected to impact loading. This empirical-based Delamination Reduction Trend (DRT) is developed based on an extensive series of low-velocity impact tests using specimens of different laminate thicknesses, stitch densities and stitch thread linear (mass) densities, subjected over a range of impact energy levels. The DRT simply relates two parameters: normalized delamination area (DelamNorm) and stitch fiber volume fraction (Vft), to characterize the effectiveness of stitching in impact damage suppression. DRT evidently shows a bi-linear behavior: first, …


Effect Of Stitch Density And Stitch Thread Thickness On Low-Velocity Impact Damage Of Stitched Composites, Kwek Tan, N. Watanabe, Y. Iwahori Apr 2015

Effect Of Stitch Density And Stitch Thread Thickness On Low-Velocity Impact Damage Of Stitched Composites, Kwek Tan, N. Watanabe, Y. Iwahori

Dr. Kwek-Tze Tan

Effect of stitch density and stitch thread thickness on low-velocity impact damage of stitched composites is investigated experimentally. Physical examination on damage surfaces shows that stitches perform as crack initiators, as well as crack arrestors. Longer matrix cracks are observed in densely-stitched composites, in contrast to isolated matrix cracks found in moderately-stitched composites. Ultrasonic C-scan evidently compares the delamination areas and concludes that specimens with higher stitch density and thread thickness are more capable of impeding delamination growth by effectively bridging delamination cracks. Load–time curves reveal that the onset of delamination is not influenced by stitch density and thread thickness. …


Effect Of Stitch Density And Stitch Thread Thickness On Compression After Impact Strength And Response Of Stitched Composites, Kwek Tan, N. Watanabe, Y. Iwahori, T. Ishikawa Apr 2015

Effect Of Stitch Density And Stitch Thread Thickness On Compression After Impact Strength And Response Of Stitched Composites, Kwek Tan, N. Watanabe, Y. Iwahori, T. Ishikawa

Dr. Kwek-Tze Tan

In this paper, the damage failure and behaviour of stitched composites under compression after impact (CAI) loading are experimentally investigated. This study focuses on the effect of stitch density and stitch thread thickness on the CAI strength and response of laminated composites reinforced by through-thickness stitching. Experimental findings show that stitched composites have higher CAI failure load and displacement, which corresponds to higher energy absorption during CAI damage, mainly attributed to greater energy consumption by stitch fibre rupture. The coupling relationships between CAI strength, impact energy, stitch density and stitch thread thickness are also revealed. It is understood that the …