摘要 |
In the present invention, there is disclosed a surface-alloyed cylindrical, partly cylindrical or hollow cylindrical structural member, consisting of an aluminium matrix casting alloy (1) and a precipitation zone (3) extending as far as the upper surface of the structural member, comprising an aluminium based alloy with precipitated hard phases, where between the matrix (1) and the precipitation zone (3) there is a eutectic zone (2) supersaturated by primary hard phases and the increase in hardness from the matrix to the surface of the structural member takes place stepwise. |