A new industrial single-module 10kW fiber laser based on 915nm wavelength pump source

High-power fiber lasers attracts considerable attentions due to many merits such as high efficiency, excellent beam quality, flexible output wavelength, simple structure which is conducive to thermal management and so on, which have become the representative of the third generation of lasers. With the industrialization of domestic fiber lasers accelerating, 10kW fiber lasers have become the mainstream of industrial laser processing in the future. At present, industrial 10kW fiber lasers are mainly realized by multi-module beam combination. Limited by nonlinear effects, single-module 10kW fiber lasers reported by various research institutions are mainly realized with 976nm wavelength pump source. In this article, we introduce the main factors that limit the power increase of high-power single-module fiber lasers, and analyzes the advantages and disadvantages of using 915nm wavelength and 976nm wavelength pump source from an application perspective. We adopte a new scheme of high-power fiber lasers using the homemade Ytterbium doped fiber, pump combiner and 915nm wavelength pump source in a MOPA system, in which we achieve 12.2kW output power. In addition, the output optical cable is a 30-meter 100/360 output, and the optical efficiency is more than 43%. The cutting speed of medium and thin slab for carbon steel and stainless steel has been significantly improved, the machine is aged for 500 hours at a water temperature of 28°≅, and the output power is not obviously reduced, which is completely satisfied for the requirements of industrial processing.