Energy density analysis on single tracks formed by selective laser melting with CoCrMo powder material

Abstract

Selective laser melting (SLM) is an advanced manufacturing technology based on layer by layer building to produce solid parts from metallic powder (Kruth et al., CIRP Ann Manuf Technol 56:730-760, 2007). Commercial SLM machines are configured to use specific parameters to process different metallic powder grades. This paper proposes a methodology that makes it possible to analyze the effect of energy density on the formation of single tracks from CoCrMo powder, using a noncommercial machine to select process parameters with open source technology. Full factorial experimental work was carried out to produce single tracks under different combinations of process parameters. A major application of this research work is to develop more flexible machine configurations applicable to different materialsThis work was carried out, in part, with the support of grants from the European Commission project IREBID (FP7-PEOPLE-2009-IRSES-247476) and the Spanish Science and Innovation Minister project TECNIPLAD (DPI2009-09852

The Influence of Process Parameters on the Surface Roughness of a 3D-Printed Co–Cr Dental Alloy Produced via Selective Laser Melting

“…To establish the optimal process parameters, an objective function (F) was determined [12,13]. This considers the relationship between the melting zone area (A1) and the penetration zone (A2), as follows: F = A1/A2 (Equation (2)), where A1 = (W1 + W3/2) × H1 (Equation (3)), in which H1 and W1 are the height and width, respectively, of the upper part of the line.…”

“…The Ra of each specimen was recorded using the average value of five readings. To establish the optimal process parameters, an objective function (F) was determined [12,13]. This considers the relationship between the melting zone area (A 1 ) and the penetration zone (A 2 ), as follows:…”

“…However, the line formation was also compromised when the energy density was excessive (type 1, Figure 3) [13,17]. When the energy density was greater than 6.6 J/mm, a single fused line with significantly coarsened balling was observed (Figure 3).…”

“…When the surface energy was reduced, the melt became highly instable; this resulted in the production of rough lines consisting of a number of small balls and/or partial melting on their surfaces. However, the line formation was also compromised when the energy density was excessive (type 1, Figure 3) [13,17]. When the energy density was greater than 6.6 J/mm, a single fused line with significantly coarsened balling was observed (Figure 3).…”

On the formation of AlSi10Mg single tracks and layers in selective laser melting: Microstructure and nano-mechanical properties

“…showed that the selection of a layer thickness is influenced by two main factors: the powder particle size distribution and the extent of shrinkage during the process. Ciurana et al (2013) used a tilted platform to investigate the effect of layer thickness, laser power, and scan speed, simultaneously, on CoCrMo single tracks and defined the threshold for the energy density to avoid single track defects. There are fewer studies with attention focusing on Al alloys.…”