Surface Quality Research for Selective Laser Melting of Ti-6Al-4V Alloy

Abstract

One of the innovative technology of producing the components is Selective Laser Melting (SLM) belongs to additive manufacturing techniques. SLM technology has already been successfully applied in the automotive, aerospace and medical industries. Despite progress in material flexibility and mechanical performances, relatively poor surface finish still presents a significant weakness in the SLM process. The scope of the present article is the study the influence of selective laser melting parameters such as laser power, scanning speed, exposure time and hatch spacing through additive manufacturing as well as the orientation of the model corresponding to the laser beam on the surface characteristic of the components made from Ti-6Al-4V alloy. By using optimized process parameters, a low surface roughness can be obtained. In research, the machine for the selective laser melting of metal powders Renishaw AM 125 device was used. Based on experiment plan, 32 models were produced, which were examined to define the surface roughness and thus represent an influence of process parameters and the orientation on the model surface quality. The article discusses the fundamental factors determining the roughness that gives invaluable knowledge to improve the surface quality of SLM parts.

Tailoring selective laser melting process for titanium drug-delivering implants with releasing micro-channels

“…In summary, the experimental results indicate that vertical surface roughness cannot be significantly improved by optimising laser power, scanning speed or hatching spacing to meet the recommended biomedical implant roughness Ra= 1-2 μm [37]. Other parameters such as particle size distribution, layer thickness, and the position of the parts in the building platform have also shown to affect the vertical surface roughness [44][45][46]. Results from the horizontal surface roughness and the dimensional deviation of the MCs clearly indicate that an implant sample cannot simultaneously achieve an optimum dimensional deviation and horizontal surface roughness as shown in Figure 5 and Figure 7.…”

The phase transitions in selective laser-melted 18-NI (300-grade) maraging steel

“…In this technique, a focused laser beam is used to spot on the powder beds and successive melting of the powder layer with bonding to existing layers, which result is the manufacturing of 3D model. SLM technology has many advantages over other parts manufacturing technologies, including considerable material utilisation, comfortable product design, good part and production flexibility and functional properties of the obtained models using the appropriate production parameters [26][27][28][29].…”

Edge and corner effects in selective laser melting of IN 625 alloy

“…Several works were done in order to increase building rate by several times and to reduce costs by using higher layer thickness and coarser metal powders [10][11][12]. However, the increase of the layer thickness leads to the deterioration of the surface quality in the conditions in which anyway the roughness of SLM top surfaces is strongly different from the roughness of side surfaces [13].…”