Method for obtaining hard particle coatings by laser-assisted cold spraying on hard substrates

Abstract

The invention discloses a method for preparing a hard particle coating on a hard substrate through laser-assisted cold spraying. The method comprises the following steps: subjecting the hard substrate to sand blasting, wherein the hardness of the hard substrate is 300 HV; preheating a spherical hard particle with a diameter in a range of 30 to 50 mu m, wherein preheating temperature is 300 to 600 DEG C, and the hard particle is one or more selected from the group consisting of 2Cr13, 17-4PH, Ni45, Ni60 and Inconel718; carrying out spraying on the surface of the hard substrate by using compressed air having a pressure of 1.5 to 3.0 MPa and carrying the preheated hard particle; and starting laser to synchronously heat a spraying area so as to form the hard particle coating on the surface of the hard substrate, wherein laser power density is 3*10<5> to 5*10<5> W / cm<2>, and wavelength is 850 to 1060 nm. The method provided by the invention can substantially improve plastic deformation generated during collision between the hard particle and the substrate, so the binding force of the coating is improved; thus, the coating with higher stability is obtained.

Description

(1) Technical field

[0001] The invention relates to laser technology and cold spraying technology, in particular to compressed air-driven laser-assisted cold spraying technology, in particular to a method for obtaining a hard particle coating on a hard substrate by laser-assisted cold spraying. (2) Background technology

[0002] Because the cold spray technology eliminates the adverse effects of high temperature on the coating and the substrate, avoids oxidation and the generation of unnecessary phases, it is of great significance for the preparation of coatings of materials that are easily oxidized. Current research shows that cold spraying can realize metal ceramics including Al, Zn, Cu, Ni, Ca, Ti, Ag, Co, Fe, Nb, NiCr alloy, MCrAlY alloy, high melting point Mo, Ta and high hardness Cr5C2- The preparation of 25NiCr, WC-21Co and other coatings can realize the preparation of composite coatings or alloy coatings and nano-material coatings with different materials, and can fo...

Images