Authors: C. Torres-Sanchez, J.R. Corney
Addresses: Department of Mechanical Engineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK. ' Department of Design, Manufacture and Engineering Management, University of Strathclyde, Glasgow, G1 1JX, UK
Abstract: This paper presents a novel manufacturing method for cellular materials with a graded porosity distribution. The motivation for creating a gradient of porosity in materials has been inspired by nature and aspires to mimic natural structures so their intrinsic advantages (e.g., optimised mechanical properties) can be exploited. Many engineering applications (e.g., thermal, acoustics, mechanical, structural and tissue engineering) require porosity tailored structures. However, current manufacturing processes are currently unable to mass-produce these foams. In this work, low power-low frequency ultrasonic irradiation has been used to excite polymeric foaming melts that, once solidified, contained different porosity distributions throughout in their solid matrix. This was possible by controlling the amount of energy imposed on the samples. The generation of porosity gradients that resembles those of natural cellular structures (e.g., bones, stems) opens up new opportunities in the design and manufacture of bio-inspired materials that can solve challenging technological problems.
Keywords: porosity gradient; bio-inspired structures; polymeric foam; cellular structures; manufacturing strategy; ultrasound; topography; design engineering; acoustic field; cellular materials; ultrasonic irradiation; bio-inspired materials; biomimicry; biomimetics; nature-inspired design; bio-inspired design.
International Journal of Design Engineering, 2011 Vol.4 No.1, pp.5 - 22
Published online: 21 Jul 2011 *Full-text access for editors Access for subscribers Purchase this article Comment on this article