Microstructure of Ti-Cr nanoparticles prepared by electrical wire explosion

The reaction products of electrical wire explosion with 25at% Cr-coated Ti wire were identified as β-TiCr₂, A-Ti, /3(Ti,Cr) and α-TiCr₂ based on the selected area electron diffraction patterns. There was a bimodal size distribution where Ti-Cr particles were 40-50 nm in size, and fine particles less than 10 nm were determined to be pure Ti or Cr. The Ti-Cr nanoparticles are not only a mixture of Ti-Cr phases but they are also heterogeneous themselves at a single particle level, due to the non-equilibrium effects of the EWE process. The very rapid collision and subsequent coalescence of Ti and Cr atom clusters are believed to have contributed to the formation of chemically segregated particles.