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

• We obtained the two phase Ni–Cu–P/Ni–Fe–B amorphous composite by melt spinning.
• We produced the lamellar composite with the microstructure of wood-like appearance.
• We found coincidence between the ductile fracture and the two phase microstructure.
• We found the layer between amorphous strips due to homogenizing of the two liquids.

The purpose of the research is to identify the differences in the final microstructure, fracture and short range order of the Ni55Fe20Cu5P10B10 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 Ni55Fe20Cu5P10B10, Ni40Fe40B20 and Ni70Cu10P20 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 Ni55Fe20Cu5P10B10 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.