Ni₃Si has excellent resistance to corrosion in strong oxidizing acids, including sulfuric acid. This material self-passivates in strong oxidizing solutions by forming a SiO₂ coating. Due to relatively low ductilities at RT and intermediate temperature ductility minimums, alloying additions are required, some of which reduce the corrosion resistance. Several alloys based on Ni-Si-Nb have been developed to specifications requiring good mechanical properties, castability, weldability, and machinabilty. Preliminary work has shown that these alloys have a good chance of becoming excellent thermal spray coatings and can be optimized to maximize their protection of the substrate with less restrictive fabrication specifications. Alloying routes studied will be presented along with the results of hardness, wear, and corrosion tests. The ability of the alloys to perform in a number of different applications will be discussed.