Influence of selective laser melting scanning speed parameter on the surface morphology, surface roughness, and micropores for manufactured Ti6Al4V parts

Purpose The purpose of this paper is to investigate the track evolution and surface characteristics of selective laser melting Ti6Al4V. Design/methodology/approach In the present paper, Ti6Al4V single-track, multi-track and bulk sample were formed at different scanning speed by selective laser melting (SLM). Then, the surface morphology, three-dimension profile and surface roughness were evaluated. The width of the single and multi-track was measured and compared. Findings The results showed that the heat accumulation played a great role on the evolution of tracks and surface characteristics from single-track to multi-track and to bulk. The surface morphology of the subsequent tracks became more regular when the single-track was irregular at the same high scanning speed. The width of last track Wn was always larger than that of the first track W1. The Ra of the top of the bulk increased with the increase of the scanning speed, this trend was as same as the Ra of the single-track, but the trend of Ra of the side was opposite. Originality/value The effect of heat accumulation on the track evolution and surface characteristics is obtained. The results can help to derive a smooth surface with a regular and continuous track in SLM.

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Collaborative Optimization on Density and Surface Roughness of 316L Stainless Steel in Selective Laser Melting

10.20944/preprints202002.0225.v1 ◽

2020 ◽

Author(s):

Yong Deng ◽

Zhongfa Mao ◽

Nan Yang ◽

Xiaodong Niu ◽

Xiangdong Lu

Keyword(s):

Surface Roughness ◽

Stainless Steel ◽

Relative Density ◽

Selective Laser Melting ◽

Laser Power ◽

316L Stainless Steel ◽

Scanning Speed ◽

Processing Parameters ◽

Collaborative Optimization ◽

Laser Melting

Although the concept of additive manufacturing has been proposed for several decades, momentum of selective laser melting (SLM) is finally starting to build. In SLM, density and surface roughness, as the important quality indexes of SLMed parts, are dependent on the processing parameters. However, there are few studies on their collaborative optimization in SLM to obtain high relative density and low surface roughness simultaneously in the previous literature. In this work, the response surface method was adopted to study the influences of different processing parameters (laser power, scanning speed and hatch space) on density and surface roughness of 316L stainless steel parts fabricated by SLM. The statistical relationship model between processing parameters and manufacturing quality is established. A multi-objective collaborative optimization strategy considering both density and surface roughness is proposed. The experimental results show that the main effects of processing parameters on the density and surface roughness are similar. It is noted that the effects of the laser power and scanning speed on the above objective quality show highly significant, while hatch space behaves an insignificant impact. Based on the above optimization, 316L stainless steel parts with excellent surface roughness and relative density can be obtained by SLM with optimized processing parameters.

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Investigation of selective laser melting process for Cu-5Sn alloy on surface roughness, microstructure and mechanical property

Rapid Prototyping Journal ◽

10.1108/rpj-12-2020-0307 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Peng Yang ◽

Dingyong He ◽

Zengjie Wang ◽

Zhen Tan ◽

Hanguang Fu ◽

...

Keyword(s):

Mechanical Properties ◽

Mechanical Property ◽

Surface Roughness ◽

Selective Laser Melting ◽

High Strength ◽

Melting Process ◽

Scanning Speed ◽

Laser Melting ◽

Forming Process ◽

Content Type

Purpose In this research, the highly dense bulk Cu-5Sn alloy specimens were fabricated using selective laser melting (SLM). This study aims to establish the relationship between laser power (LP), scanning speed (SS) and hatch space (HS) with surface roughness (Ra) and density. To obtain Cu-5Sn alloy formed parts with high strength and low surface roughness. The microstructure and mechanical properties of SLMed Cu-5Sn were investigated. Design/methodology/approach The relative density (RD) was optimized using the response surface method (RSM) and analysis of variance. First, the Ra of SLMed formed specimens was studied to optimize the forming process parameters with a good surface. Then, the dense specimens were studied by ANOVA and the RSM to obtain dense specimens for mechanical property analysis. Findings Dense specimens were obtained by RSM and ANOVA. The tensile properties were compared with the casted specimens. The yield and ultimate strengths increased from 71 and 131 MPa for the cast specimens to 334 and 489 MPa for the SLMed specimens, respectively. The ductility increased significantly from 11% to 23%, due to the refined microstructure of the SLMed specimens, as well as the formation of many twin crystals. Originality/value The Ra, RD and mechanical properties of SLM specimens Cu-5Sn were systematically studied, and the influencing factors were analyzed together. This study provides a theoretical and practical example to improve the surface quality and RD.

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Influence of laser parameters on the surface morphology of slurry-based Al2O3 parts produced through selective laser melting

Rapid Prototyping Journal ◽

10.1108/rpj-12-2016-0201 ◽

2018 ◽

Vol 24 (2) ◽

pp. 333-341 ◽

Cited By ~ 6

Author(s):

Kai Zhang ◽

Tingting Liu ◽

Wenhe Liao ◽

Changdong Zhang ◽

Yishuai Yan ◽

...

Keyword(s):

Surface Morphology ◽

Surface Quality ◽

Selective Laser Melting ◽

Laser Power ◽

High Performance ◽

Thermocapillary Convection ◽

Scanning Speed ◽

Laser Melting ◽

Content Type ◽

Laser Parameters

Purpose The purpose of this paper is to obtain high-performance ceramics and enrich additive manufacturing of ceramic parts. Also, a new manufacturing technique based on slurry by selective laser melting (SLM) was studied, which has some significant advantages compared to indirect selective laser sintering of ceramic powders. Design/methodology/approach To study the effect of laser parameters on the surface morphology and melting state of pure Al2O3 ceramics, laser power varied between 100 and 200 W and scan speed varied between 60 and 90 mm/s. Findings Experimental results show that Al2O3 slurry melts completely when the laser power is about 200 W and the scanning speed is 90 mm/s. Surface quality cannot be improved effectively by changing the scanning speed. However, surface quality improves when the laser power is 200∼205 W and energy density is 889∼911 J/mm3. Thermocapillary convection was observed during SLM. By changing the temperature gradient, streak convection and flowing Bénard cells were obtained during SLM of Al2O3 slurry. Originality/value It is feasible to produce slurry ceramic parts without binders through SLM. Increasing the laser power is the most effective way to fully melt the ceramics. Complex thermocapillary convection was observed during this new process; it may be used to produce crystals.

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

Archives of Metallurgy and Materials ◽

10.1515/amm-2016-0213 ◽

2016 ◽

Vol 61 (3) ◽

pp. 1291-1296 ◽

Cited By ~ 28

Author(s):

M. Król ◽

T. Tański

Keyword(s):

Surface Roughness ◽

Additive Manufacturing ◽

Surface Quality ◽

Selective Laser Melting ◽

Process Parameters ◽

Scanning Speed ◽

Innovative Technology ◽

Metal Powders ◽

Laser Melting ◽

Influence Of Process Parameters

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.

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The Surface Morphology and Electrochemical Properties of Pure Titanium Obtained by Selective Laser Melting Method

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.308.21 ◽

2020 ◽

Vol 308 ◽

pp. 21-32

Author(s):

Anna Woźniak ◽

Marcin Adamiak ◽

Bogusław Ziębowicz

Keyword(s):

Corrosion Resistance ◽

Surface Morphology ◽

Electrochemical Properties ◽

Selective Laser Melting ◽

Laser Power ◽

Pure Titanium ◽

Scanning Speed ◽

Laser Melting ◽

High Corrosion Resistance ◽

High Corrosion

High requirements in biomedical application are associated with biocompatibility and high corrosion resistance of metal biomaterials, which are used equally in joint and bon substitution and the healing and renewal of bone weaknesses. In this paper the surface morphology and electrochemical properties of samples manufactured by Selective Laser Melting SLM method using pure titanium Grade II powder material are explored. The tested samples were produced divided into four group, depended on the values of basic process parameters – laser power P, scanning speed SP and point distance PD. The value of energy density E delivered to the sintered material was constants and was an approximately E = 75 ± 2 J/mm3. In the paper, the pitting corrosion test by recording anodic polarization curves and electrochemical spectroscopy test were carried out. Additionally the microscopic observation and microchemical analysis by SEM/EDS analysis and material density measurements were performed too. Based on the obtained results it can be concluded that the laser power P and scanning speed SP have a significant affect on the obtained full density defect free material with high corrosion resistance.

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Collaborative Optimization of Density and Surface Roughness of 316L Stainless Steel in Selective Laser Melting

Materials ◽

10.3390/ma13071601 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1601 ◽

Cited By ~ 2

Author(s):

Yong Deng ◽

Zhongfa Mao ◽

Nan Yang ◽

Xiaodong Niu ◽

Xiangdong Lu

Keyword(s):

Surface Roughness ◽

Stainless Steel ◽

Relative Density ◽

Selective Laser Melting ◽

Laser Power ◽

316L Stainless Steel ◽

Scanning Speed ◽

Processing Parameters ◽

Collaborative Optimization ◽

Laser Melting

Although the concept of additive manufacturing has been proposed for several decades, momentum in the area of selective laser melting (SLM) is finally starting to build. In SLM, density and surface roughness, as the important quality indexes of SLMed parts, are dependent on the processing parameters. However, there are few studies on their collaborative optimization during SLM to obtain high relative density and low surface roughness simultaneously in the literature. In this work, the response surface method was adopted to study the influences of different processing parameters (laser power, scanning speed and hatch space) on density and surface roughness of 316L stainless steel parts fabricated by SLM. A statistical relationship model between processing parameters and manufacturing quality is established. A multi-objective collaborative optimization strategy considering both density and surface roughness is proposed. The experimental results show that the main effects of processing parameters on the density and surface roughness are similar. We observed that the laser power and scanning speed significantly affected the above objective quality, but the influence of the hatch spacing was comparatively low. Based on the above optimization, 316L stainless steel parts with excellent surface roughness and relative density can be obtained by SLM with optimized processing parameters.

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Improving surface quality in selective laser melting based tool making

Journal of Intelligent Manufacturing ◽

10.1007/s10845-021-01744-9 ◽

2021 ◽

Author(s):

Filippo Simoni ◽

Andrea Huxol ◽

Franz-Josef Villmer

Keyword(s):

Surface Roughness ◽

Additive Manufacturing ◽

Surface Quality ◽

Selective Laser Melting ◽

Melting Process ◽

Laser Remelting ◽

Laser Melting ◽

Great Cost ◽

Starting Point ◽

Processing Techniques

AbstractIn the last years, Additive Manufacturing, thanks to its capability of continuous improvements in performance and cost-efficiency, was able to partly replace and redefine well-established manufacturing processes. This research is based on the idea to achieve great cost and operational benefits especially in the field of tool making for injection molding by combining traditional and additive manufacturing in one process chain. Special attention is given to the surface quality in terms of surface roughness and its optimization directly in the Selective Laser Melting process. This article presents the possibility for a remelting process of the SLM parts as a way to optimize the surfaces of the produced parts. The influence of laser remelting on the surface roughness of the parts is analyzed while varying machine parameters like laser power and scan settings. Laser remelting with optimized parameter settings considerably improves the surface quality of SLM parts and is a great starting point for further post-processing techniques, which require a low initial value of surface roughness.

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Directionally-Dependent Mechanical Properties of Ti6Al4V Manufactured by Electron Beam Melting (EBM) and Selective Laser Melting (SLM)

Materials ◽

10.3390/ma14133603 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3603

Author(s):

Tim Pasang ◽

Benny Tavlovich ◽

Omry Yannay ◽

Ben Jakson ◽

Mike Fry ◽

...

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Tensile Strength ◽

Electron Beam ◽

Additive Manufacturing ◽

Selective Laser Melting ◽

Electron Beam Melting ◽

Rolling Direction ◽

Laser Melting ◽

Plate Rolling

An investigation of mechanical properties of Ti6Al4V produced by additive manufacturing (AM) in the as-printed condition have been conducted and compared with wrought alloys. The AM samples were built by Selective Laser Melting (SLM) and Electron Beam Melting (EBM) in 0°, 45° and 90°—relative to horizontal direction. Similarly, the wrought samples were also cut and tested in the same directions relative to the plate rolling direction. The microstructures of the samples were significantly different on all samples. α′ martensite was observed on the SLM, acicular α on EBM and combination of both on the wrought alloy. EBM samples had higher surface roughness (Ra) compared with both SLM and wrought alloy. SLM samples were comparatively harder than wrought alloy and EBM. Tensile strength of the wrought alloy was higher in all directions except for 45°, where SLM samples showed higher strength than both EBM and wrought alloy on that direction. The ductility of the wrought alloy was consistently higher than both SLM and EBM indicated by clear necking feature on the wrought alloy samples. Dimples were observed on all fracture surfaces.

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