Mechanical properties of luffa sponge.

The paper presents the first scientific study of the stiffness, strength and energy absorption characteristics of the luffa sponge with a view to using it as an alternative sustainable engineering material for various practical applications. A series of compression tests on luffa sponge columns have been carried out. The stress-strain curves show a near constant plateau stress over a long strain range, which is ideal for energy absorption applications. It is found that the luffa sponge material exhibits remarkable stiffness, strength and energy absorption capacities that are comparable to those of some metallic cellular materials in a similar density range. Empirical formulae have been developed for stiffness, strength, densification strain and specific energy absorption at the macroscopic level. A comparative study shows that the luffa sponge material outperforms a variety of traditional engineering materials.