Laser cladding technology is a new surface modification technology that emerged in the 1970s with the development of high-power lasers. In the 1970s, AVCO of the United States conducted research on laser cladding technology for many easily worn parts of automobile engines. According to the different ways of supplying cladding materials, laser cladding process methods are divided into laser cladding alloy presetting method and alloy synchronous powder feeding method. The addition of cladding materials usually has three forms: powder, wire and plate, among which powder is the most commonly used.
Laser cladding technology was first applied for a patent by Gnanamuthu of ACVO EVERETT RES LABINC of the United States at the end of 1974, thus opening the prelude to the basic research work of this technology.
In the 1980s, laser cladding became a cutting-edge topic in the field of surface strengthening. During this period, researchers conducted in-depth research on the principles, processes and materials of laser cladding.
In the 1990s, laser cladding technology produced huge benefits in engineering applications. Its biggest feature is the conversion of mass manufacturing into targeted individual manufacturing.
After entering the 21st century, with the gradual maturity of high-power laser technology, the industrialization of laser cladding technology has developed rapidly.
Laser cladding is a process method that uses laser as a heat source to melt the filler material (powder, wire or plate) and the substrate surface together to form a cladding layer that is metallurgically bonded to the substrate surface, thereby significantly improving its surface wear resistance, corrosion resistance, heat resistance, oxidation resistance and electrical properties. Compared with other surface strengthening technologies, laser cladding technology has the characteristics of high laser energy density, fast heating speed, small heat-affected area on the substrate, small thermal deformation of the workpiece, fast cooling speed, fine coating grains, dense structure, low coating dilution rate, metallurgical bonding between the coating and the substrate and high bonding strength, wide material selectivity, easy automation and no environmental pollution.
In recent years, laser cladding technology has been continuously developed and innovated, and has been widely used in many industries such as aerospace, mining machinery, petrochemicals, automobiles, ships, electricity, and railways. For example, in the aerospace field, it can be used for the manufacture and repair of large aluminum alloys and aircraft engine blades; in the field of oil exploration, it can restore the original performance of parts such as drill collars and enhance their service life; in the coal mining industry, it can effectively improve the corrosion resistance of hydraulic columns and extend their life; in the power industry, it can be used to repair turbine rotors and blades. At the same time, this technology also faces some challenges, such as the disconnection between industry, academia and research, and high costs. In the future, laser cladding technology will develop in the direction of multidisciplinary cross-cutting, systematic integration, large-area cladding and quality control, and miniaturized in-situ repair.
