1. Core Reasons for Compatibility
Low carbon content: Its carbon content (~0.14–0.22%) is moderate, avoiding excessive hardening or cracking of the cut edge (unlike high-carbon steels).
Good thermal conductivity: The material absorbs laser energy evenly, reducing localized overheating and ensuring smooth cuts.
Minimal alloy interference: Trace alloy elements do not significantly affect laser absorption or melt flow, unlike high-alloy steels (e.g., stainless steel) that may require higher laser power.
2. Typical Laser Cutting Parameters (Reference)
Assist gas: Oxygen is preferred for most thicknesses-it accelerates combustion of the material, increasing cutting speed and producing a clean edge. For thin plates (<3mm), nitrogen can be used to avoid oxidation (if a rust-free edge is required).
3. Advantages of Laser Cutting for Q235NH
High precision: Narrow kerf width (0.1–0.3mm) and minimal thermal deformation, suitable for complex shapes (e.g., architectural decorative parts, mechanical components).
Smooth cut edge: The cut surface is flat with no burrs; post-processing (e.g., deburring) is minimal or unnecessary.
Efficiency: Faster than plasma cutting for thin-to-medium thicknesses, with lower material waste.
4. Notes for Practical Operation
Surface cleaning: Remove oil, rust, or debris from the plate surface before cutting-contaminants can cause uneven cutting or damage the laser lens.
Thickness limit: Laser cutting is most efficient for Q235NH plates ≤25mm. For thicker plates (>25mm), plasma cutting or flame cutting may be more cost-effective.
Edge protection: After cutting, the bare edge (without a rust layer) is prone to corrosion. Consider applying a temporary rust inhibitor or accelerating the formation of a uniform rust layer (as discussed in prior questions) to protect the edge.
