Net-shape Al6061/SiC nanocomposites by powder injection moulding

Net-Shape Al6061-0.5vol.%SiC nanocomposites were produced by powder injection moulding. Nano-sized SiC powders were produced by inductively coupled plasma synthesis and mixed with gas atomized Al6061powder in a high energy planetary ball mill. 2 wt.% of Sn powder was added as a sintering aid to perform a liquid phase sintering. A feedstock containing 55 vol.% of powder and 45 vol.% of binder (low density polyethylene, paraffin wax and stearic acid) was prepared in a double sigma mixer under protective atmosphere. The solid loading was composed of equal fractions of gas atomized Al6061 spherical powder and mechanical milled nanocomposite powder, with 2wt.% Sn. The green parts were first solvent debinded in a heptane bath, to remove both paraffin wax and stearic acid. Then, thermal debinding and sintering were performed in a MIM furnace. The mechanical properties of the net-shape parts were measured by tensile tests and Vickers microhardness. For comparison MIM Al6061 parts were also produced by the same process.