Laser cladding, also known as laser cladding or laser cladding, is a new surface modification technology. It adds cladding material on the surface of the substrate and uses a high-energy density laser beam to make it together with the thin layer of the substrate surface Melting, forming a filler cladding layer combined with smelting alloy on the surface of the substrate.
Because laser cladding can cladding high melting point materials on the surface of low melting point substrates, and the composition of the material is not restricted by the usual thermodynamic conditions of smelting alloys, the range of cladding materials used is quite wide , Including nickel-based, cobalt-based, iron-based alloys, carbide composite alloy materials and ceramic materials, among which the laser cladding of alloy materials and carbide composite materials is relatively mature and has been practically applied. In addition, due to the nearly adiabatic rapid heating process produced by the high energy density of the laser beam, laser cladding has less thermal effect on the substrate and causes less deformation. Controlling the input energy of the laser can also limit the dilution of the substrate to a very low level (generally 2%-8%), thereby maintaining the excellent performance of the original cladding material.
Therefore, this technology aims to improve the wear resistance and corrosion resistance of the material surface, and is mainly used for repairing large and valuable parts after wear and enhancing the performance of newly manufactured parts.
5. Application of laser in micro processing
In the early 1990s, with the research and application of micromachined manufacturing technology and MEMS (Micro Electric Mechanical System), the emerging branch of laser processing, “laser microprocessing” is booming. Laser micro-processing generally refers to processing with a feature size of less than 100 μm, and is a major processing technology in micro-machine manufacturing.
The essence of laser processing is that the laser transfers energy to the processed material, and the processed material undergoes physical or chemical changes to achieve the purpose of processing. The laser microfabrication process can process more complex microstructures, and the required conditions are not as harsh as the heterosexual etching and LIGA technology. It is easier to achieve in laboratories and factories, and because the laser has high time and high spatial resolution The high efficiency makes it possible to be further promoted and applied in occasions that require high-precision processing (such as electronics, semiconductors, communications and other industries), so laser micromachining poses a huge challenge to ordinary micromachining.