Effects of core grain orientation on the mechanical properties of wood sandwich composite

Abstract

Utilization of sandwich composite during recent year has been driven by the fact that composite
material has ultimately high strength and stiffness by weight than any other materials. The skins of
sandwich composites technically bear most of the applied loads, however, the core materials also
play an important role as it functions in providing continuous support to resist the shear stress.
Hence, proper selection of core materials is required to establish a sturdy sandwich composite
structure. This paper presents an experimental investigation on the sandwich structure consists of
fibreglass/epoxy face skins and a mahang wood core. Sandwich composite with core grain oriented
in parallel and perpendicular to the flat plane direction were tested for mechanical performance in
tension, compression and flexure. The results indicate that sandwich composite with grain oriented
in parallel direction performed better in tensile properties with strength of 201.98 MPa whereas
sandwich composite with perpendicular core grain produced a higher value of compression
properties with strength of 70.11 MPa. However, no significant effect of grain orientation was
observed in flexural strength. The strength of sandwich composite is dependent on the grain
alignment of the wood core as it functions exclusively as mechanical supporting cells to support
the wood structure.