Recent Advancements in Post Processing of Additively Manufactured Metals Using Laser Polishing

Abstract

The poor surface roughness associated with additively manufactured parts can influence the surface integrity and geometric tolerances of produced components. In response to this issue, laser polishing (LP) has emerged as a potential technique for improving the surface finish and producing parts with enhanced properties. Many studies have been conducted to investigate the effect of LP on parts produced using additive manufacturing. The results showed that applying such a unique treatment can significantly enhance the overall performance of the part. In LP processes, the surface of the part is re-melted by the laser, resulting in smaller peaks and shallower valleys, which enable the development of smoother surfaces with the help of gravity and surface tension. Precise selection of laser parameters is essential to achieve optimal enhancement in the surface finish, microstructure, and mechanical properties of the treated parts. This paper aims to compile state-of-the-art knowledge in LP of additively manufactured metals and presents the optimal process parameters experimentally and modeling using artificial machine learning. The effects of laser power, the number of laser re-melting passes, and scanning speed on the final surface roughness and mechanical properties are comprehensively discussed in this work.

Fe-Mn-Al-Ni Shape Memory Alloy Additively Manufactured via Laser Powder Bed Fusion

“…Higher roughness can be explained by the existence of irregular structures in low VED cases and the emergence of essentially flat regions in higher VED cases due to neighboring melt pools that can fuse together at various locations in the case of higher VED [61]. Applying the socalled "laser polishing method" is one other procedure that can be utilized to reduce surface roughness in addition to optimizing the fabrication's processing parameters, as highlighted in [62]. A crucial element that needs to be investigated is surface roughness (SR), as AM of metallic alloys can produce intricately shaped components with interior surfaces that are difficult to post-machine [58].…”

Investigation of Surface Integrity of Conical Hole in Laser Polishing 440C Stainless Steel

“…Abrasive flow polishing is a viable alternative for internal surface polishing of components [9][10][11], and the process is time-consuming and requires a substantial duration to achieve a satisfactory surface finish. Laser polishing, on the other hand, offers numerous advantages, such as high efficiency, non-pollution, and the ability to selectively polish specific areas [12][13][14]. It has also demonstrated effectiveness on inclined surfaces and complex surface geometry [15][16][17].…”