ABSTRACT

In this work, two typical surface characteristics, i.e., mean surface roughness and angle of the kerf during laser processing of 3D-printed Polylactic Acid (PLA) plates with 4.00 mm in thickness, are investigated. A carbon dioxide laser was utilized to separate 27 work pieces of rectangular shape. The governing laser parameters, speed of cutting and laser power, were varied according to full factorial experimental methodology. An orthogonal array (OA) having nine combinations was implemented, and nine specimens were cut with the same set-up and the same parameters three times (27 replicates in total). The experimental results were analyzed using descriptive statistical analysis, i.e., histograms, box plots, interaction charts and optimized using analysis of means (ANOM) plots as well as ANOVA analysis. The data analysis indicated that laser speed is the dominant parameter for the kerf angle, whilst both the laser velocity and power are important for mean surface roughness of the cut surface for PLA 3D-printed parts. The spread of the data is smaller in Y direction, which indicates that the weaving phenomenon affects the laser cut performance.

摘要

在这项工作中，研究了厚度为 4.00 毫米的 3D 打印聚乳酸 (PLA) 板在激光加工过程中的两个典型表面特征，即平均表面粗糙度和切口角度。二氧化碳激光器被用来分离27个矩形工件。控制激光参数、切割速度和激光功率根据全因子实验方法而变化。实施了具有九种组合的正交阵列 (OA)，并以相同的设置和相同的参数切割了 9 个试样 3 次（共 27 个重复）。使用描述性统计分析（即直方图、箱线图、交互作用图）分析实验结果，并使用均值分析（ANOM）图以及方差分析进行优化。数据分析表明，激光速度是切口角的主要参数，而激光速度和功率对于 PLA 3D 打印部件切割表面的平均表面粗糙度都很重要。数据在 Y 方向的扩散较小，这表明编织现象影响了激光切割性能。