Experimental characterization of concrete removal by high-power quasicontinuous wave fiber laser irradiation

The performance of high-power quasicontinuous wave fiber laser irradiation on concrete has been investigated in the downward (along the gravitational direction) and the upward laser directions (against it). Mechanism of material removal without an assist gas is dominated by vaporization and melts expulsion induced by recoil pressure evaporation. Also, the melt concrete ejection is greatly enhanced by expansion via gaseous bubbles and breakup. The performance of laser irradiation on concrete is significantly enhanced in the upward direction by the assistance of gravity. In addition, the laser parameters can control the quality and performance of laser drilling and cutting of concrete. Furthermore, the thermal effect analysis determines the impact of laser power on the concrete surface, which may help to consider the heat affected zone coupled with the analyses of material property around the laser treated region. (C) 2017 Laser Institute of America.