The ornamental design for an aluminumchair, as shown and described.
FIG. 1 is a perspective view of an aluminum chair, showing my new design, with armrests each having a wine glass stem holder near the front ends thereof, and a phantom portion in the seatback that includes optional types of ornamentation;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken line shown on the backrest of the drawing is for illustrative purposes only and forms no part of the claimed design.