A novel process for manufacturing copper with size-controlled in-situ tungsten nanoparticles by casting

In this study, a novel molten-salt-assisted in-situ synthesis method was developed to cast copper (Cu) containing uniformly distributed tungsten (W) nanoparticles using tungsten oxide (WO3) microparticles as the precursor. With WO3 microparticles dissolved by molten KAlF4 and reduced by molten aluminum (Al), W nanoparticles were formed in the Cu matrix and their sizes were significantly reduced compared to the ex-situ incorporation method. The size of W nanoparticles was controlled by the synthesis parameters, which was studied theoretically and experimentally. An average size of the W nanoparticles as small as 132.7 nm in the Cu matrix can be achieved by controlling WO3 concentration in molten salt and synthesis time. The in-situ Cu/W nanocomposites exhibit enhanced mechanical properties due to the effective nanoparticle size control. For in-situ Cu/5.6 vol.% W, it exhibits a Young's modulus of 137.2 GPa and a microhardness of 100.9 HV, 20.4 % and 50.6 % higher than Cu respectively. This work paves a new way to fabricate metals reinforced by uniformly distributed sizecontrolled nanoparticles through regular casting for widespread applications.

Automated summary

A novel molten-salt-assisted in-situ synthesis method was developed to cast Cu containing uniformly distributed W nanoparticles in the matrix. The size of W nanoparticles in the Cu matrix was significantly reduced compared to the ex-situ incorporation method, and the synthesis parameters played a key role in controlling the size of W nanoparticles, leading to enhanced mechanical properties of the nanocomposites. This work opens up a new pathway for fabricating metals reinforced by size-controlled nanoparticles through regular casting for diverse applications.