Method for preparing iron-based mixed crystal coating through base material preheating assisted laser cladding

The invention discloses a method for preparing an iron-based mixed crystal coating through laser cladding assisted by preheating of a base material, and belongs to the technical field of preparation of amorphous coatings through laser cladding. The amorphous powder used for cladding comprises the following elements in percentage by mass: 50%-55% of Fe, 15%-20% of Cr, 25%-30% of Mo, 0-6% of Nb, 3%-5% of C and 1%-2% of B; then vacuum gas atomization is carried out under high-purity argon atomization to prepare cladding amorphous powder; screening out powder with the particle size range of 100-200 meshes, drying in a drying box, heating below the base material by utilizing an induction heater, keeping the preheating temperature of the base material constant by adjusting the temperature of the induction heater, and then injecting the powder into a metal molten pool radiated by laser through carrier gas under the argon protective atmosphere by adopting a coaxial powder feeding laser cladding technology; and the ir