Characterization of a Gelcast AISI 310 SS Matrix Composite Reinforced by Alumina and GNP Particles

Gelcasting is a versatile forming technique suitable for preparing composite materials with various powders, including metallic and ceramic particles, at any solids concentration. Despite its potential, the application of gelcasting to produce metal matrix composites reinforced with alumina and graphene remains limited. This study investigates the gelcasting of AISI 310 stainless steel composites reinforced with 1, 3, and 5 vol.% nanosized alumina and 0.5 vol.% graphene nanoplatelets (GNPs). Rheological behavior and particle interactions were analyzed to ensure uniform dispersion. Thermal analysis determined optimal sintering conditions, avoiding densification issues. Compression and microhardness tests revealed yield strengths of up to 285 MPa at room temperature (RT) and 140 MPa at 800 °C, exceeding ASTM A351/A351M-18e1 standards. Microstructural refinement and homogeneous alumina distribution were achieved, with 3 vol.% alumina providing the best performance. The gelcasting process proved effective for producing dense, mechanically robust composites at a low cost.