Microstructure and fracture surface of the two-component melt-spun amorphous/amorphous composite

The purpose of the research is to identify the differences in the final microstructure, fracture and short range order of the Ni ₅₅Fe ₂₀Cu ₅P ₁₀B ₁₀ alloy melt-spun after the ejection of the homogeneous liquid from the standard single chamber crucible and from the crucible with double chamber as the flux of two liquids i.e.: Ni–Fe–B and Ni–Cu–P. The preparation of the alloys involved remelting Ni ₅₅Fe ₂₀Cu ₅P ₁₀B ₁₀, Ni ₄₀Fe ₄₀B ₂₀ and Ni ₇₀Cu ₁₀P ₂₀ compositions in the arc furnace under titanium gettered argon atmosphere starting from pure metals 99.95 wt.% Ni, 99.95 wt.% Fe, 99.95 wt.% Cu and Ni–B, Fe–B, Ni–P, and Cu–P master alloys. The Ni ₅₅Fe ₂₀Cu ₅P ₁₀B ₁₀ melt-spun ribbons were obtained by means of two methods: the first one was melt-spun from a traditional single chamber crucible while the second one was produced using two component melt spinning (TCMS) performed in the protective helium atmosphere. The research was conducted by using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Mössbauer spectroscopy. The results of the microstructure examination show that the TCMS alloy is amorphous/amorphous composite and boundaries between the stripes of the differentiated chemical composition coincide with the features of the ductile fracture. The Mössbauer spectroscopy of the alloys confirms that the special feature of the TCMS alloy is that it is composed of the regions with differentiated chemical composition.