In laser cutting technology, the laser output mode is one of the key factors that determines the processing mechanism and cutting performance. According to the temporal distribution of laser energy output, lasers are mainly classified into continuous lasers and pulsed lasers. These two laser types exhibit different energy coupling characteristics, thermal interaction behaviors, and processing adaptability in cutting applications.
I. Characteristics of Continuous Lasers in Cutting Applications
A continuous laser refers to a laser that outputs a stable laser beam at a constant power during operation. The laser energy is continuously distributed over time, and the material remains under constant thermal loading throughout the cutting process.
During cutting, the continuous laser continuously heats the material surface, causing the temperature to rise rapidly. When the temperature reaches the melting point or vaporization point, a stable molten pool is formed. With the assistance of auxiliary gas, the molten material is effectively expelled from the kerf, enabling continuous material separation.
Due to the stable energy input, continuous laser cutting provides good molten pool stability and kerf continuity, making it suitable for long cutting paths and complex contour processing. However, the sustained heat input also causes thermal diffusion within the material, resulting in a relatively larger heat-affected zone. Edge regions may experience thermal deformation or microstructural changes.
Continuous laser cutting is widely used in medium- and thick-plate metal processing, such as industrial cutting of carbon steel, stainless steel, and aluminum alloys. It is particularly suitable for applications with high requirements for cutting efficiency and production throughput.
II. Characteristics of Pulsed Lasers in Cutting Applications
A pulsed laser outputs short-duration, high-energy laser pulses at a specific repetition frequency. The laser energy is distributed intermittently over time. Each pulse has an extremely short duration but a high peak power.
In cutting applications, pulsed lasers act on the material surface through instantaneous high energy density, causing localized regions to rapidly melt or vaporize. Material removal is achieved progressively through pulse-by-pulse superposition, and the cutting process manifests as continuous accumulation of micro-scale material removal.
Because the interaction time of each pulse is very short, heat has insufficient time to diffuse into surrounding areas. As a result, pulsed laser cutting produces a smaller heat-affected zone and has a limited impact on material microstructure and edge morphology. This characteristic provides clear advantages in precision cutting and processing of heat-sensitive materials.
Pulsed lasers are commonly used for thin metal sheets, precision components, micro-holes, and narrow kerf processing. They are also suitable for high-reflectivity materials or applications with strict requirements for cut edge quality.
III. Influence of Energy Interaction Mode on Cutting Performance
The differences in cutting performance between continuous and pulsed lasers fundamentally arise from differences in the temporal and spatial distribution of laser energy. Continuous lasers emphasize stable energy input and continuous melting, making them more suitable for efficiency-oriented cutting. Pulsed lasers rely on high peak power to achieve precise material removal, placing greater emphasis on thermal control and machining accuracy.
In practical cutting processes, continuous lasers typically demonstrate higher cutting speeds and stronger capability for thick-plate processing, while pulsed lasers show advantages in piercing capability, edge quality control, and suppression of thermal effects.
IV. Practical Considerations for Cutting Process Selection
When selecting between continuous and pulsed lasers for cutting applications, factors such as material thickness, thermal conductivity, reflectivity, and required processing accuracy must be considered comprehensively. For large-format plates and structural part blanking, continuous lasers are more aligned with industrial production requirements. For precision machining, thin-material cutting, or special material processing, pulsed lasers offer better process adaptability.
In certain applications, power modulation of continuous lasers can be employed to achieve quasi-pulsed processing behavior, allowing a balance between cutting efficiency and thermal effect control.
Continuous lasers and pulsed lasers play different process roles in cutting applications. They exhibit fundamental differences in energy output characteristics, material interaction mechanisms, and applicable cutting ranges. A clear understanding of the working principles of both laser types, combined with specific processing requirements, is essential for achieving stable cutting quality and improving overall processing efficiency.