 Commercial aluminum-MWNT composites have strengths comparable to stainless steel (0.7 to 1 GPa) at one-third the density (2.6 g cm−3), comparable to more expensive aluminium-lithium alloys.CNTs can serve as a multifunctional coating material.For example, paint/MWNT mixtures can reduce biofouling of ship hulls by discouraging attachment of algae and barnacles.