Advances in Engineering Advances in Engineering features breaking research judged by Advances in Engineering advisory team to be of key importance in the Engineering field. Papers are selected from over 10,000 published each week from most peer reviewed journals.
International Journal of Impact Engineering, Volume 60, October 2013, Pages 120-132.
R.A.W. Mines, S. Tsopanos, Y. Shen, R. Hasan, S.T. McKown.
School of Engineering, University of Liverpool, The Quadrangle, Liverpool L69 3GH, UK.
Abstract
The paper addresses the low velocity, drop weight behaviour of small (100 mm by 100 mm) sandwich panels with CFRP skins. The main point of interest is the core material, and the focus of the paper is in the use of body centred cubic (BCC) micro lattice cores made from Ti 6Al 4V titanium alloy and 316L stainless steel manufactured using selective laser melting. The mechanical behaviour of the micro lattice core is compared to that of conventional aluminium honeycomb. The paper discusses the manufacture and characterisation of the core materials, the measurement of core properties from strut tensile tests, block compression tests and the drop weight impact performance of the panels. Impact performance is expressed in terms of panel penetration. It is shown that the current Ti 6Al 4V BCC micro lattice cores are competitive with aluminium honeycomb, but that there is scope for improvement in Ti 6Al 4V micro strut mechanical properties. The SLM manufacturing process gives lattice structures with open cell architecture, which is an advantage for aerospace applications, and the SLM process can be used to realise a variety of cell lattice geometries.
Additional Information
The photo shows a section of an aerospace sandwich panel after impact at low velocity with a hemispherical impactor. This simulates foreign object impact of aerospace wing and fuselage structures, and the point of interest is the stainless steel micro lattice core. This is manufactured using the 3D printing process of selective laser melting, and the SLM process has the potential to realise core materials with tailored parent material properties and lattice topologies specific to the structural application. Core materials in titanium alloy can also be made.
