The overall objective of this work is to develop a radiation shielding material system that is sufficiently strong to serve as a load bearing structure. Such a materials system does not currently exist. The ideal shielding material for space applications should preferably be light weight with good mechanical strength and good thermal conductivity. We propose a novel approach to fabricate reinforced composite materials for radiation shielding applications using a powder metallurgy approach with sintering via the innovative Field Assisted Sintering Technology (FAST). The composite materials that we propose include various compositions of boron carbide (B4C) and tungsten carbide (WC) in either an aluminum matrix or in a polymer matrix of ultra-high molecular weight polyethylene (UHMWPE). FAST (also called spark plasma sintering- SPS) is an innovative process that sinters powder with near 100% theoretical density and very limited to no grain growth. FAST is a one step process that is highly flexible and robust, with short processing cycles (100-1000 times faster). It is much more cost effective in comparison to conventional compaction and sintering methods, and it is also amenable to large scale production.