Surface finish in laser solid freeform fabrication of an AISI 303L stainless steel thin wall

Laser solid freeform fabrication is a flexible manufacturing technique that can be used to produce a near net shape component by consolidation of successive deposited layers of additive materials. This study investigates the effects of the main process parameters, the laser power and scanning speed, on the surface finish of AISI 303L thin walls through reducing the thickness of the deposited layers. To study the effects of the variations of the operating parameters, the process is simulated. The numerical results showed that by increasing the scanning speed the laser power must be adjusted in order to maintain the melt pool maximum temperature within a pre-defined value. In this way, the surface finish of the fabricated walls considerably improves due to the decreased thickness of each individual layer without significantly disturbing the melt pool and the main physical characteristics of the build-ups. This was also verified through experimentally fabrication of the walls and their microstructural examination.