Effect of Process Parameters on the Quality of Laser-Cut Stainless Steel Thin Plates

Abstract

At present, laser cutting is currently employed to cut metallic plates, due to their good finish and dimensional quality, as well as because of the flexibility of the process to obtain different shapes. In the present paper, surface roughness, dimensional accuracy, and burr thickness of thin plates of 0.8 mm are studied as functions of different process parameters: pulse frequency, pulse width, and speed. Eight different experiments were performed according to a full 23 factorial design, with two replicates each. Square specimens of 10 mm × 10 mm were cut. Arithmetical mean roughness Ra was measured with a contact roughness meter, and the dimensions and burr thickness with a micrometer. Ra values ranged between 1.89 and 3.86 µm, dimensional error values between 0.22 and 0.93%, and burr thickness between 2 and 34 µm. Regression analysis was performed, and linear models were obtained for each response. Results showed that roughness depends mainly on frequency, on the interaction of frequency and pulse width and on pulse width. The dimensional error depends on pulse width, frequency, and the interaction between pulse width and speed. Burr thickness is influenced by frequency, pulse width, and the interaction between frequency and speed. Multi-objective optimization showed that, in order to simultaneously minimize the three responses, it is recommended to use high frequency (80 Hz), high pulse width (0.6 ms), and high speed (140 mm/min). The present study will help to select appropriate laser cutting conditions in thin plates, in order to favor good surface finish and dimensional accuracy, as well as low burr thickness.

Nickel–Titanium Alloy Laser Micromachining: A Review of Nitinol Laser Processes and Optimization for High‐Speed Laser Cutting

“…Stainless steel laser cut rates have been shown to have an average value of 11.1 mm s À1 for thicknesses ranging from 80 to 10 000 μm. [138,[179][180][181][182][183] Studies have shown that in order to produce dross-and HAZ-free cuts in Nitinol with thicknesses ranging from 100 to 2540 μm, a slow 1.9 mm s À1 average cut rate is required for femtosecond laser cutting. [51,150,178,184,185] This goes back to the relationship provided by Holder et al [122] where in order to increase the ablation depth for a femtosecond pulse, the pulse energy must be increased.…”

Optimization of nitrogen use efficiency in cutting of austenitic stainless steel by a fiber laser

“…The success of oxygen or nitrogen cutting depends on the focus distance, which needs to be well adjusted to the upper surface of the metal sheet. On Figure 3 could be seen when cutting with oxygen, the focus must be above the upper surface of the sheet, and when cutting with nitrogen, the focus must be on or slightly above the lower surface of the sheet [8,9].…”

Analysis of the Surface Stereometry of Alloyed Austenitic Steel after Fibre Laser Cutting using Confocal Microscopy

“…The process is more complicated in the case of thermal cutting due to the low melting point. It is recommended to use a high speed and optimum laser power, suitable for the thickness, in order to obtain low surface roughness [35][36][37][38][39]. Taking into account the above literature data, it can be concluded that cutting speed and auxiliary gas pressure are the most significant parameters affecting the change in surface porosity, while the impact of laser power is much less [40][41][42].…”