Parametric Study of the Effect of Feed Speed and Power on Laser Cut Quality of 4130 Steel
Samples of 4130 steel were cut by a CO2 laser and the effects of power and feed rate on kerf width, surface roughness, striation frequency and the size of heat affected zone (HAZ) were studied. It was observed that power had a major effect on kerf width and size of HAZ, while feed rate affects were secondary. In the other hand, surface roughness and striation frequency were affected most by feed rate. At low power levels the smallest kerf width and HAZ are obtained and the effect of feed rate is moderate. Low feed rates gave good surface roughness and low striation frequency. For optimum cut quality, kerf width, HAZ and surface roughness are kept minimum. However operating conditions that satisfy these requirements while maintaining high productivity could not be identified.
The Effect of Laser Parameters on Cutting Metallic Materials
This experimental study investigated the effect of laser parameters on the machining of SS41 and SUS304. The metallic materials play an important role in engineering applications. They are widely used in high-tech industries such as aerospace, automotive, and architecture. Due to the development of technology and high-tech industrialization, the various processing technologies are being developed with the requirement of high precision. However, the conventional cutting process is difficult to meet high precision processing. Therefore, to achieve high precision processing of the SS41 and SUS304, laser manufacturing has been applied. The current study investigated the process quality of laser cutting for SS41 and SUS304, with the usage of a continuous wave CO2 laser cutting system. The experimental variables are set to the laser cutting speed, laser power, and different engineering materials. The results are significantly affected by the laser parameters. As the result, the process quality of the laser cutting has been observed by measuring the top and bottom kerf widths, as well as the size of the melting zone and Heat Affected Zone (HAZ) according to volume energy. In addition, the evaluation of the laser processing parameters is significantly important to achieve optimal cutting quality. Therefore, we observed the correlation between the laser parameters and cutting quality. These were evaluated by analysis of variance (ANOVA) and multiple regression analysis. The experimental results of kerf top, kerf bottom, melting width, and HAZ on the laser parameters are properly predicted by multiple regression. In addition, the effect of laser parameters on the materials is determinant by the percentage of contribution of ANOVA.
LASER CUTTING OF STEELS: A physical and chemical analysis of the particles ejected during cutting. Part II
This paper is a continuation of work published in an earlier edition of this journal[1]. Both papers deal with the results of a detailed analysis of the particles ejected from the cut zone during laser cutting of mild and stainless steels. Reference 1 presented the thermochemical data and discussion generated by the experimental investigation. This paper concentrates on the physical characteristics and metallography of the particles. Analysis techniques used included: Scanning Electron Microscopy, optical microscopy, metallography and particle sizing. The results from this extensive analysis have enabled the authors to postulate oxidation histories for the particles. In addition to this it has been possible to explain the variation in particle size for various material thicknesses.