Effect of high layer thickness on surface quality and defect behavior of Ti-6Al-4V fabricated by selective laser melting

Purpose – This paper aims to present the application aspect of the work to manufacturing premolar and molar dental crowns by selective laser melting (SLM) of pure gold. Over the years different metals have been processed using laser-based Additive Manufacturing processes, but very little work has been published on the SLM of gold (Au). Previously published work presented suitable processing parameters for SLM of pure gold. Design/methodology/approach – Suitable processing parameters were used to manufacture premolar and molar dental crowns using SLM system. Different layer thickness was used to analyse the effect on surface quality of crowns. Mechanical properties are checked using nanoindentation and micro Computerized Tomography scanning. Findings – Dental crowns were successfully manufacturing using new build platform and suitable processing parameters. Parts were manufacturing using minimal supports which prevented parts from damaging during removal. A bed temperature of 100°C was found suitable for reducing warpage in the layers. Layer thickness of 50μm was found to have better surface quality and structural integrity as compared to 75μm. Porosity was found to be predominantly inter-layer. Small difference in mechanical properties of dental crowns is associated with the laser processing. Originality/value – This research is the first of its kind which presents dental crown manufacturing using SLM of pure gold.

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Performance of High Layer Thickness in Selective Laser Melting of Ti6Al4V

Materials ◽

10.3390/ma9120975 ◽

2016 ◽

Vol 9 (12) ◽

pp. 975 ◽

Cited By ~ 42

Author(s):

Xuezhi Shi ◽

Shuyuan Ma ◽

Changmeng Liu ◽

Cheng Chen ◽

Qianru Wu ◽

...

Keyword(s):

Layer Thickness ◽

Selective Laser Melting ◽

Laser Melting ◽

High Layer

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Research on High Layer Thickness Fabricated of 316L by Selective Laser Melting

Materials ◽

10.3390/ma10091055 ◽

2017 ◽

Vol 10 (9) ◽

pp. 1055 ◽

Cited By ~ 15

Author(s):

◽

...

Keyword(s):

Layer Thickness ◽

Selective Laser Melting ◽

Laser Melting ◽

High Layer

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Effect of layer thickness on the overhanging surface quality manufactured by selective laser melting

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/09544062211052820 ◽

2021 ◽

pp. 095440622110528

Author(s):

Weipeng Duan ◽

Meiping Wu ◽

Jitai Han ◽

Yiqing Ma ◽

Xiaojin Miao

Keyword(s):

Experimental Data ◽

Optimal Condition ◽

Layer Thickness ◽

Surface Quality ◽

Selective Laser Melting ◽

Molten Pool ◽

Laser Melting ◽

Surface Flatness ◽

Increasing Demand ◽

The Relationship

With the increasing demand for the precision of lightweight part, overhanging surface quality has attracted more and more attentions in recent years. In this work, the relationship between overhanging surface quality and layer thickness was studied. The testing results revealed that with the increasing of the layer thickness, surface quality, especially the surface flatness, showed a significant decreasing trend due to the decreasing of the bending deformation. When layer thickness was ranged from 0.15 to 0.18, it reached a relative optimal condition while the sinking distance and flatness within 0.095 mm–0.1 mm and 0.076 mm–0.078 mm, respectively. With the further increasing of the layer thickness, both sinking distance and surface flatness had a quite significant decreasing due to the increasing gravity of the overhanging layer powder and bonded powder caused by the molten pool sinking. Combined to the experimental data and the analysis given above, the structure of the overhanging surface was optimized and the surface quality showed a further increase.

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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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Optimization of selective laser melting process parameters for surface quality performance of the fabricated Ti6Al4V

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-021-06953-3 ◽

2021 ◽

Author(s):

Moses Oyesola ◽

Khumbulani Mpofu ◽

Ntombi Mathe ◽

Samuel Fatoba ◽

Shaik Hoosain ◽

...

Keyword(s):

Surface Quality ◽

Selective Laser Melting ◽

Process Parameters ◽

Melting Process ◽

Laser Melting ◽

Quality Performance ◽

Selective Laser Melting Process

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A SIMULATION STUDY ON THE EFFECT OF PARTICLE SIZE DISTRIBUTION ON THE PRINTED GEOMETRY IN SELECTIVE LASER MELTING

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4052705 ◽

2021 ◽

pp. 1-14

Author(s):

Vaishak Ramesh Sagar ◽

Samuel Lorin ◽

Johan Göhl ◽

Johannes Quist ◽

Christoffer Cromvik ◽

...

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Layer Thickness ◽

Selective Laser Melting ◽

Laser Melting ◽

Powder Bed ◽

Mean Particle Size ◽

Final Layer ◽

Effect Of Particle Size

Abstract Selective laser melting (SLM) process is a powder bed fusion additive manufacturing process that finds applications in aerospace and medical industries for its ability to produce complex geometry parts. As the raw material used is in powder form, particle size distribution (PSD) is a significant characteristic that influences the build quality in turn affecting the functionality and aesthetics aspects of the product. This paper investigates the effect of PSD on the printed geometry for 316L stainless steel powder, where three coupled in-house simulation tools based on Discrete Element Method (DEM), Computational Fluid Dynamics (CFD), and Structural Mechanics are employed. DEM is used for simulating the powder bed distribution based on the different powder PSD. The CFD is used as a virtual testbed to determine thermal parameters such as heat capacity and thermal conductivity of the powder bed viewed as a continuum. The values found as a stochastic function of the powder distribution is used to analyse the effect on the melted zone and deformation using Structural Mechanics. Results showed that mean particle size and PSD had a significant effect on the packing density, melt pool layer thickness, and the final layer thickness after deformation. Specifically, a narrow particle size distribution with smaller mean particle size and standard deviation produced solidified final layer thickness closest to nominal layer thickness. The proposed simulation approach and the results will catalyze in development of geometry assurance strategies to minimize the effect of particle size distribution on the geometric quality of the printed part.

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