The Mechanism of Forming Coagulated Particles in Selective Laser Melting of Cobalt-Chromium-Molybdenum Powder

Abstract

Selective laser melting (SLM) is thought to be a prospective manufacturing technology of complex metal components. Formation of coagulated particles when melting is reported to be an important factor for target mechanical properties of the end product. This paper discusses the effect of SLM parameters, including laser output power, laser movement velocity, preheating temperature of the powder, laser beam diameter on the mechanism of forming coagulated particles in melting cobalt-chromium-molybdenum powdered material. The study shows that a rise of power to 60 W at a scanning velocity 6 mm/s causes coagulated particles to expand to 350 μm; that is far bigger than a size of powder in as delivered state (90 μm). The work investigates the effect of mechanical activation of cobalt-chromium-molybdenum powder on dimensions of coagulated particles. The research data can be applied to the improvement of up-to-date optimization approaches to manufacturing process parameters in SLM technology.

Advances in Laser Additive Manufacturing of Cobalt–Chromium Alloy Multi-Layer Mesoscopic Analytical Modelling with Experimental Correlations: From Micro-Dendrite Grains to Bulk Objects

“…Various experiments have been carried out to correlate the operating conditions with the average grain size. Laser additive manufacturing (LAM) techniques can be classified into laser powder bed fusion (LPBF) and laser melting deposition (LMD) [ 9 , 10 , 11 ]. The rate of heating and solidification play an important role on the final average grain size grain size [ 12 , 13 , 14 ].…”

Heat Transfer, Molten Pool Flow Micro-Simulation, and Experimental Research on Molybdenum Alloys Fabricated via Selective Laser Melting

“…Maamoun et al studied the interaction between SLM process parameters by analyzing relative density, porosity, surface roughness, and dimensional accuracy [ 9 ]. Saprykin et al discussed the influence of parameters such as light output power, laser moving speed, and preheating temperature on the formation mechanism of solidified particles during powder melting [ 10 ]. Furthermore, in recent years, many studies also have reported on laser powder bed fusion simulation.…”