Papers by Keyword: Solid State Amorphization

Abstract: Fast electron irradiation can induce the solid-state amorphization (SSA) of many intermetallic compounds. The occurrence of SSA stimulated by fast electron irradiation was found in the Al_0.5TiZrPdCuNi high-entropy alloy (HEA). The relationship between the occurrence of SSA in intermetallic compounds under fast electron irradiation and the empirical alloy parameters for predicting the solid-solution-formation tendency in HEAs was discussed. The occurrence of SSA in intermetallic compounds was hardly predicted, only by the alloy parameters of δ or ΔH_mix, which have been widely used for predicting solid-solution formation in HEAs. All intermetallic compounds with ΔH_mix ≤ -35 kJ/mol and those with δ ≥ 12.5 exhibit the occurrence of SSA. This implies that the intermetallic compounds with a largely negative ΔH_mix value and a largely positive δ parameter are favorable for the occurrence of SSA.

Abstract: Metallic plates were coated mechanically with powders by surface treatment in a SPEX 8000 Mixer Mill. Al disks were coated by harder Ni particles, while a Zr-Ti powder blend was deposited onto Cu targets. The microstructure and morphology of the coatings were investigated by scanning electron microscopy and X-ray diffraction. Mechanical properties were studied by dynamic hardness tests.

Abstract: The comprehensive computer simulation study of the phase diagram of the repulsive step potential system in three dimensions is represented. We show that the system with a simple purely repulsive isotropic potential demonstrates a number of unusual features. The maxima and minima on the melting curve are found for some regions of potential parameters. It is shown that the phase diagram in ρ-T plane includes two isostructural crystalline parts separated by the disordered phase which is amorphous at low enough temperatures. Phase diagram in the (P-T) plane shows that the transition to the amorphous state occurs approximately along the extrapolated spinodals. Structural FCC-BCC phase transition is found at high densities.