Effects of process parameters and scanning patterns on quality of thin-walled copper flanges manufactured by selective laser melting

With superior flexible manufacturing capability, selective laser melting (SLM) has attracted more and more attention in the aerospace, medical, and automotive industries. However, the poor quality of the lower surface in overhanging structures is still one of the factors that limits the wide application of SLM. In this work, the influence of process parameters and scanning strategy on the lower surface quality of SLMed TA15 (Ti-6Al-2Zr-1Mo-1V) titanium alloy parts were studied. The results showed that the laser surface energy density (EF) had a significant influence on the quality of the lower surface. Excessive EF led to obvious sinking of the molten pool and a serious slag hanging phenomenon. However, the too low EF easily contributed to the insufficient powder fusion in the lower surface area, which led to the agglomeration of a molten pool during core processing, resulting in slag hanging, pores, and powder spalling that reduced the quality of the lower surface. Moreover, the cross-remelting strategy and non-remelting strategy gained better surface quality at the low EF and high EF, respectively. In addition, it was found that the quality of the lower surface could be quickly and accurately evaluated by the cooling time of the molten pool during the processing of the lower surface. This research can increase the understanding of the forming mechanism of the lower surface and has certain guiding significance for the process optimization of the lower surface.

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Influence of process parameters on surface quality of CoCrMo produced by selective laser melting

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-015-7040-3 ◽

2015 ◽

Vol 80 (5-8) ◽

pp. 985-995 ◽

Cited By ~ 36

Author(s):

Yurivania Pupo ◽

Karla P. Monroy ◽

Joaquim Ciurana

Keyword(s):

Surface Quality ◽

Selective Laser Melting ◽

Process Parameters ◽

Laser Melting ◽

Influence Of Process Parameters

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A Study on Effect of Different Process Parameters on the Quality of Overhang Surface Produced by Selective Laser Melting

Volume 1: Additive Manufacturing; Bio and Sustainable Manufacturing ◽

10.1115/msec2018-6421 ◽

2018 ◽

Author(s):

Sagar Sarkar ◽

Ankit Porwal ◽

Nuthalapati Yaswanth ◽

Ashish Kumar Nath

Keyword(s):

Aspect Ratio ◽

Selective Laser Melting ◽

Process Parameters ◽

Support Structures ◽

Metal Powders ◽

Laser Melting ◽

Scanning Strategy ◽

Support Structure ◽

Laser Process

Selective Laser Melting process enables production of geometrically complex parts directly from CAD model by melting metal powders layer by layer. For successful building of parts, some auxiliary structures namely support structures are also built to ensure proper heat conduction from actual parts to be built to the base plate. Support structures are needed if there are overhang surfaces in the design of the part. If the design of the part is very complex and features many overhang surfaces, then too many supports get generated. After building the part, these support structures need to be removed properly to get desired geometrical features and it may deteriorate the surface quality from where supports are removed. Sometimes removal of support structures becomes very difficult specially for parts having internal features. In this study, first effect of inclined angle, aspect ratio and different scanning strategies on the quality of overhang surfaces produced without any support structure under constant laser power and scan speed has been investigated. Scanning Electron Microscopy (SEM) images of overhang surfaces have been analyzed to investigate the presence of warping and uneven fused edges if any. It was found that with increase in inclined angles and aspect ratio, warping and presence of uneven fused edges increases. Rotational scanning strategy found to be better than linear alternate scanning strategy for reduced uneven fused edges formation and warping. Results show an overhang without any support structure can be built successfully with a single laser process parameters upto 25.343 degree which is less than theoretical critical angle of 26.565 degree. Further, it has been shown, using a novel strategy of building overhang with multiple laser process parameters, it is possible to build overhang even upto 24.132 degree.

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Selective Laser Melting of the Inconel 718 Nickel Superalloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.698.333 ◽

2014 ◽

Vol 698 ◽

pp. 333-338 ◽

Cited By ~ 6

Author(s):

Vadim Sh. Sufiiarov ◽

Evgenii V. Borisov ◽

Igor A. Polozov

Keyword(s):

Selective Laser Melting ◽

Process Parameters ◽

Inconel 718 ◽

Melting Process ◽

Nickel Superalloy ◽

Mechanical Tests ◽

Laser Melting ◽

Influence Of Process Parameters ◽

Inconel 718 Superalloy

The results of the research on selective laser melting process of the Inconel 718 superalloy powder under conditions of additive manufacturing of parts for special purposes are presented. The influence of process parameters on the quality of manufactured parts is shown. Process parameters which allow manufacturing parts with the density close to 100%, are determined. Also, the results of mechanical tests and investigation of microstructure are presented.

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The Effect of Selective Laser Melting Process Parameters on the Microstructure and Mechanical Properties of Al6061 and AlSi10Mg Alloys

Materials ◽

10.3390/ma12010012 ◽

2018 ◽

Vol 12 (1) ◽

pp. 12 ◽

Cited By ~ 26

Author(s):

Ahmed Maamoun ◽

Yi Xue ◽

Mohamed Elbestawi ◽

Stephen Veldhuis

Keyword(s):

Mechanical Properties ◽

Selective Laser Melting ◽

Process Parameters ◽

High Strength ◽

Melting Process ◽

Laser Melting ◽

Influence Of Process Parameters ◽

Wide Range ◽

Powder Characteristics

Additive manufacturing (AM) offers customization of the microstructures and mechanical properties of fabricated components according to the material selected and process parameters applied. Selective laser melting (SLM) is a commonly-used technique for processing high strength aluminum alloys. The selection of SLM process parameters could control the microstructure of parts and their mechanical properties. However, the process parameters limit and defects obtained inside the as-built parts present obstacles to customized part production. This study investigates the influence of SLM process parameters on the quality of as-built Al6061 and AlSi10Mg parts according to the mutual connection between the microstructure characteristics and mechanical properties. The microstructure of both materials was characterized for different parts processed over a wide range of SLM process parameters. The optimized SLM parameters were investigated to eliminate internal microstructure defects. The behavior of the mechanical properties of parts was presented through regression models generated from the design of experiment (DOE) analysis for the results of hardness, ultimate tensile strength, and yield strength. A comparison between the results obtained and those reported in the literature is presented to illustrate the influence of process parameters, build environment, and powder characteristics on the quality of parts produced. The results obtained from this study could help to customize the part’s quality by satisfying their design requirements in addition to reducing as-built defects which, in turn, would reduce the amount of the post-processing needed.

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Effect of Selective Laser Melting Process Parameters on the Quality of Al Alloy Parts: Powder Characterization, Density, Surface Roughness, and Dimensional Accuracy

Materials ◽

10.3390/ma11122343 ◽

2018 ◽

Vol 11 (12) ◽

pp. 2343 ◽

Cited By ~ 43

Author(s):

Ahmed Maamoun ◽

Yi Xue ◽

Mohamed Elbestawi ◽

Stephen Veldhuis

Keyword(s):

Surface Roughness ◽

Selective Laser Melting ◽

Process Parameters ◽

Dimensional Accuracy ◽

High Strength ◽

Melting Process ◽

Al Alloys ◽

Al Alloy ◽

Laser Melting

Additive manufacturing (AM) of high-strength Al alloys promises to enhance the performance of critical components related to various aerospace and automotive applications. The key advantage of AM is its ability to generate lightweight, robust, and complex shapes. However, the characteristics of the as-built parts may represent an obstacle to the satisfaction of the parts’ quality requirements. The current study investigates the influence of selective laser melting (SLM) process parameters on the quality of parts fabricated from different Al alloys. A design of experiment (DOE) was used to analyze relative density, porosity, surface roughness, and dimensional accuracy according to the interaction effect between the SLM process parameters. The results show a range of energy densities and SLM process parameters for AlSi10Mg and Al6061 alloys needed to achieve “optimum” values for each performance characteristic. A process map was developed for each material by combining the optimized range of SLM process parameters for each characteristic to ensure good quality of the as-built parts. This study is also aimed at reducing the amount of post-processing needed according to the optimal processing window detected.

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Optimising the process parameters of selective laser melting for the fabrication of Ti6Al4V alloy

Rapid Prototyping Journal ◽

10.1108/rpj-03-2016-0045 ◽

2018 ◽

Vol 24 (1) ◽

pp. 150-159 ◽

Cited By ~ 9

Author(s):

Zhonghua Li ◽

Ibrahim Kucukkoc ◽

David Z. Zhang ◽

Fei Liu

Keyword(s):

Surface Roughness ◽

Surface Quality ◽

Selective Laser Melting ◽

Process Parameters ◽

High Surface ◽

Optimum Process ◽

Laser Melting ◽

Vertical Side ◽

Content Type

Purpose Surface roughness is an important evaluation index for industrial components, and it strongly depends on the processing parameters for selective laser molten Ti6Al4V parts. This paper aims to obtain an optimum selective laser melting (SLM) parameter set to improve the surface roughness of Ti6Al4V samples. Design/methodology/approach A response surface methodology (RSM)-based approach is proposed to improve the surface quality of selective laser molten Ti6Al4V parts and understand the relationship between the SLM process parameters and the surface roughness. The main SLM parameters (i.e. laser power, scan speed and hatch spacing) are optimized, and Ti6Al4V parts are manufactured by the SLM technology with no post processes. Findings Optimum process parameters were obtained using the RSM method to minimise the roughness of the top and vertical side surfaces. Obtained parameter sets were evaluated based on their productivity and surface quality performance. The validation tests have been performed, and the results verified the effectivity of the proposed technique. It was also shown that the top and vertical sides must be handled together to obtain better top surface quality. Practical implications The obtained optimum SLM parameter set can be used in the manufacturing of Ti6Al4V components with high surface roughness requirement. Originality/value RSM is used to analyse and determine the optimal combination of SLM parameters with the aim of improving the surface roughness quality of Ti6Al4V components, for the first time in the literature. Also, this is the first study which aims to simultaneously optimise the surface quality of top and vertical sides of titanium alloys.

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Study of the Surface and Dimensional Quality of the AlSi10Mg Thin-Wall Components Manufactured by Selective Laser Melting

Journal of Composites Science ◽

10.3390/jcs5050126 ◽

2021 ◽

Vol 5 (5) ◽

pp. 126

Author(s):

Muhammad Waqas ◽

Dingyong He ◽

Hassan Elahi ◽

Saleem Riaz ◽

Marco Eugeni ◽

...

Keyword(s):

Additive Manufacturing ◽

Selective Laser Melting ◽

Process Parameters ◽

Wall Thickness ◽

Reference Value ◽

Dimensional Accuracy ◽

Thin Wall ◽

Laser Melting ◽

Anova Technique

Additive manufacturing (AM), a 3D printing technique that manufactures components by sequential addition of powder, has massively reshaped the manufacturing and engineering sectors from batch production to manufacturing customized, innovative, state-of-the-art, and sustainable products. Additive manufacturing of aluminum alloys by selective laser melting (SLM) is one of the latest research trends in this field due to the fact of its advantages and vast applications in manufacturing industries such as automobiles and aerospace. This paper investigated the surface and dimensional quality of SLM-built AlSi10Mg parts using a response surface method (RSM) and found the influence of the wall thickness and process parameters (i.e., laser power, scanning speed, hatch distance) on the pieces. Thin-walled test specimens of AlSi10Mg alloy were manufactured with different combinations of process parameters at three wall thicknesses: 1.0 mm, 2.0 mm, and 3.0 mm. The Minitab DOE module was used to create 27 different configurations of wall thickness and process parameters. The samples’ surface roughness and dimensional accuracy were investigated, and the findings were evaluated using the ANOVA technique. The regression model and the ANOVA technique showed high precision and had a particular reference value for practical engineering applications.

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