Surface Laser Processing of Additive Manufactured 1.2709 Steel Parts: Preliminary Study

Abstract

Recently, metal selective laser sintering (SLS) techniques have attracted lively interest as a promising technology, which offers a number of unique applications in manufacturing of metal parts with complex internal structure and geometry. However, unsatisfactory surface properties of as-manufactured SLS parts cause high cost of finish processing and restrict wider application of SLS products. The paper presents results of the study, which was taken to evaluate capability of laser processing to improve surface quality of SLS parts manufactured from powder maraging steel 1.2709 (X3NiCoMoTi 18-9-5). The properties of processed surfaces were assessed, and the main dependencies of the roughness, hardness, wear resistance, and phase composition on the main parameters of laser processing—scanning speed, laser power, and number of processing times—were determined. The roughness of surfaces was diminished up to ∼41%, the hardness was increased up to ∼88%, and the wear resistance was improved up to almost 4 times, as compared with surface of as-manufactured SLS part. The preliminary study has demonstrated that laser processing has considerable potential for improvement of surface conditions of steel additive manufactured parts.

Metal additive manufacturing in the commercial aviation industry: A review

“…In this study, they found laser process can diminish the roughness of the fabricated parts up to 41% and make a significant improvement in wear resistance using higher laser power and slowest laser speed with 4 laser passes. This study demonstrated the positive influence of laser processing for improving the surface quality of steel 3D printed products [136].…”

“…Laser processes is an applicable and flexible approach to improve the surface of additively manufactured products. During this process, the metal surface can be melted and the relocation during the liquid phase can make a smoother surface [136]. Ablation method is the other process using a laser that can evaporate the materials and the defected layer can be removed by this way from the 3D manufactured part.…”

Influence of LPBF Parameters and Strategies on Fine Machining of Pre-Built Bores

“…Total fill is the option to completely fill the hatch with adjacent border scans. Furthermore, some samples are tested with a double scan approach to examine its influence, which is adapted from Černašėjus et al [10]. Double scan means all border paths are scanned twice for each layer.…”

Laser Polishing of Additive Manufactured Aluminium Parts by Modulated Laser Power

“…Laser polishing of additive manufactured metal parts is commonly done with pulsed or continuous laser radiation. Investigations on cobalt-chromium alloys (CoCr) [15][16][17][18][19][20], Inconel 718 [21][22][23][24], Inconel 625 [25], tool steel [26], tool steel H13 [27], tool steel S136H [28], maraging steel 1.2709 [29], Titanium Ti6Al-4V [18,[30][31][32][33][34][35] and corrosion resistant steel 316L [36][37][38], 1.4542 [39] and LaserForm ST-100 [40,41] reveal roughness reduction rates between 50 and 90%.…”