▎ 摘　　要

NOVELTY - An aluminum alloy composition is obtained by adding 1-5 wt.% carbon nanotubes or 1-5 wt.% graphene to aluminum alloy containing aluminum as main component, and 5-8 wt.%, 10-13 wt.% or 15-19 wt.% silicon. The aluminum alloy composition is used for forming local strengthening layer by build-up welding in local position where abrasion resistance and durability are required in an aluminum piston (10). USE - Aluminum alloy composition is prepared in form of metal powder to-be-used in welding, welding bar or filler metal for forming local strengthening layer of piston (all claimed). ADVANTAGE - The lightweight aluminum piston consisting of local strengthening layer of aluminum alloy composition has excellent wear resistance and durability. The aluminum alloy composition is prepared in the form of metal powder to-be-used in welding, welding bar or filler metal having improved resistance to high-temperature hot-cracking phenomenon. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic side view of the aluminum piston. Aluminum piston (10) Combustion chamber (11) Pressure ring (12) Oil ring (13) Ring groove (14)