A Study of Glass-Forming Conditions of Laser-Surface-Melted Fe-Ni-Si-B-V Alloy

This paper deals with glass forming condition of laser surface melted Fe₄₀-Ni₃₆-Si₈-B₁₄-V₂ alloy by means of a CO₂ continuous laser with power of 5kW、metalloscope、X-ray diffraction and microhardness test.Amorphous surface layer can be produced by controlling the power density and the scanning speed of laser beam.The result shows that the power density and scanning speed are two important factors to produce glassy surface layers.In selecting the power density and the scanning speed,it must be considered that a high cooling rate is necessary to avoid crystalization and in the meantime a high temperature and a sufficient time are necessary to ensure the full melt of all the surface material.A single-pass glassy layer on the surface of Fe₄₀-Ni₃₆-Si₈-B₁₄-V₂ alloy can be achieved using a power density of 2.7×10⁵W·cm^-2 and a range of scanning speeds form 1.0 m·s^-1 to 2.0 m·s^-1.