Paper Review

Paper Review

Yi Jian [a], Xingwang Bai [a*], Penglei Jie [a], Lingfeng Luo [a], Min Mao [a], Changjun Qiu [a], Zebin Zhu [b], Yuguo Kang [b]

[a] School of Mechanical Engineering, University of South China, Hengyang, Hunan, 421001, PR China

[b] Dadi Special Exploration Team of National Mine Emergency Rescue, Bei'jing 100040, China

Optics and Laser Technology IF: 5.0 [Published: 2026]

This study investigates the material removal mechanisms and parameter influences in remote laser cutting of concrete without the use of assisted gas, which is a critical requirement for long-distance rescue and facility demolition. Due to the absence of auxiliary gas to blow away molten slag, the material removal rate in long-distance operations remains relatively low. The research identifies that the primary methods of material removal are splattering, slag dripping, and crack propagation. Splattering is caused by instantaneous vaporization from localized high temperatures, while slag dripping results from gravitational drainage of molten glass through the kerf. Furthermore, crack propagation is induced when internal vapor pressure exceeds the tensile strength of the concrete, leading to structural failure. Experimental results demonstrate that for a 50 mm-thick concrete sample at a distance of 14 m, the cutting speed can reach $1~mm/s$ at 2 kW and $2~mm/s$ at 4 kW. It was found that choosing a positive defocusing (+2 m) configuration significantly enhances performance by enlarging the kerf width and promoting better slag dripping. Additionally, the study proposes a reciprocating cutting method which involves multiple repeated passes; this approach was shown to increase the material removal rate by 11.3% compared to single-pass cutting by re-cutting and ejecting solidified slag deposits. These findings provide a vital parameter basis for improving the efficiency and quality of remote laser cutting in complex emergency and decommissioning scenarios.