Alloy powder for preparation of nickel-based amorphous composite coating layer and preparation method thereof

The invention discloses an alloy powder for preparation of a nickel-based amorphous composite coating layer and a preparation method thereof. The alloy powder comprises the components by mass percentage: 29-32% of Fe, 3-5% of B, 5-7% of Si, 7-9% of Nb, 1-3% of C, and the balance Ni. The preparation method comprises the steps: after preheating prepared raw materials, loading into an electric furnace, melting, when the temperature is risen to 1450-1550 DEG C, adding a deoxidant, exhausting gas, removing slag, stirring, then standing for 3-5 minutes, discharging out of the furnace, and thus obtaining an alloy liquid; then injecting the alloy liquid into a powder making device, under the inert gas protection or a vacuum state, atomizing the alloy, and making the alloy into a 100-300 mesh powder. The prepared nickel-based amorphous composite coating layer has a hardness value higher than that of a traditional nickel-based amorphous coating layer, has good mechanical and tribological properties, and has good application prospects in key mechanical components having higher requirements on the tribological properties.