Effects of processing parameters and heat treatment on thermal conductivity of additively manufactured AlSi10Mg by selective laser melting

Gas atomized Ti-6Al-4V (Ti64) alloy powder was used to prepare distinct designed geometries with different properties by selective laser melting (SLM). Several heat treatments were investigated to find suitable processing parameters to strengthen (specially to harden) these parts for different applications. The results showed significant differences between tabulated results for heat treated billet Ti64 and SLM produced Ti64 parts, while certain mechanical properties of SLM Ti64 parts could be improved by different heat treatments using different processing parameters. Most heat treatments performed followed the trends of a reduction in tensile strength while improving ductility compared with untreated SLM Ti64 parts.Gas nitriding [GN] (diffusion-based thermo-chemical treatment) has been combined with a selected heat treatment for interstitial hardening. Heat treatment was performed below β-transus temperature using minimum flow of nitrogen gas with a controlled low pressure. The surface of the SLM produced Ti64 parts after gas nitriding showed TiN and Ti2N phases (“compound layer”, XRD analysis) and α (N) – Ti diffusion zones as well as high values of micro-hardness as compared to untreated SLM produced Ti64 parts. The microhardness profiles on cross section of the gas nitrided SLM produced samples gave information about the i) microhardness behaviour of the material, and ii) thickness of the nitrided layer, which was investigated using energy dispersive spectroscopy (EDS) and x-ray elemental analysis. Tensile properties of the gas nitrided Ti64 bars produced by SLM under different conditions were also reported.

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Additive manufacturing of CMSX-4 Ni-base superalloy by selective laser melting: Influence of processing parameters and heat treatment

Additive Manufacturing ◽

10.1016/j.addma.2019.100874 ◽

2019 ◽

Vol 30 ◽

pp. 100874 ◽

Cited By ~ 2

Author(s):

Inmaculada Lopez-Galilea ◽

Benjamin Ruttert ◽

Junyang He ◽

Thomas Hammerschmidt ◽

Ralf Drautz ◽

...

Keyword(s):

Heat Treatment ◽

Additive Manufacturing ◽

Selective Laser Melting ◽

Processing Parameters ◽

Laser Melting ◽

Base Superalloy

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Enhanced hardness and moderate thermal conductivity of Cu-2.4Ni-0.7Si alloy processed via selective laser melting followed by suitable heat treatment

Journal of Laser Applications ◽

10.2351/1.5127559 ◽

2020 ◽

Vol 32 (1) ◽

pp. 012006

Author(s):

Yan Zhou ◽

Daobing Chen ◽

Longchen Duan ◽

Jie Gan ◽

Shifeng Wen

Keyword(s):

Thermal Conductivity ◽

Heat Treatment ◽

Selective Laser Melting ◽

Laser Melting ◽

Suitable Heat Treatment

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Microstructural and Mechanical Properties of Selective Laser Melted Al 4047

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.752-753.485 ◽

2015 ◽

Vol 752-753 ◽

pp. 485-490 ◽

Cited By ~ 9

Author(s):

Shafaqat Siddique ◽

Eric Wycisk ◽

Gerrit Frieling ◽

Claus Emmelmann ◽

Frank Walther

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Selective Laser Melting ◽

Process Parameters ◽

Processing Parameters ◽

Complex Geometries ◽

Optimal Parameters ◽

Post Processing ◽

Laser Melting ◽

Process Cost

Selective laser melting (SLM) has been recognized as a pertinent process for manufacturing of complex geometries. Al 4047 has been manufactured in this study with different processing parameters of the SLM process to obtain the optimal parameters suitable for required applications, as well as to determine the effect of these parameters and post-processing heat treatment on mechanical properties. A unique Al-Si eutectic microstructure is obtained with Al dendrites growing in the scanning direction. Mechanical properties of the SLM manufactured Al 4047 are at par with those of conventionally manufactured alloy. These properties can be varied by changing the SLM process parameters which can help controlling the process cost depending upon required mechanical properties.

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High Bending Strength Hypereutectic Al-22Si-0.2Fe-0.1Cu-Re Alloy Fabricated by Selective Laser Melting

Metals ◽

10.3390/met11040528 ◽

2021 ◽

Vol 11 (4) ◽

pp. 528

Author(s):

Chunyue Yin ◽

Zhehao Lu ◽

Xianshun Wei ◽

Biao Yan ◽

Pengfei Yan

Keyword(s):

Selective Laser Melting ◽

Bending Strength ◽

Primary Silicon ◽

Processing Parameters ◽

Powder Materials ◽

Laser Melting ◽

Maximum Value ◽

Fine Microstructure ◽

Average Size ◽

Al Matrix

The objective of the study is to investigate the corresponding microstructure and mechanical properties, especially bending strength, of the hypereutectic Al-Si alloy processed by selective laser melting (SLM). Almost dense Al-22Si-0.2Fe-0.1Cu-Re alloy is fabricated from a novel type of powder materials with optimized processing parameters. Phase analysis of such Al-22Si-0.2Fe-0.1Cu-Re alloy shows that the solubility of Si in Al matrix increases significantly. The fine microstructure can be observed, divided into three zones: fine zones, coarse zones, and heat-affected zones (HAZs). Fine zones are directly generated from the liquid phase with the characteristic of petaloid structures and bulk Al-Si eutectic. Due to the fine microstructure induced by the rapid cooling rate of SLM, the primary silicon presents a minimum average size of ~0.5 μm in fine zones, significantly smaller than that in the conventional produced hypereutectic samples. Moreover, the maximum value of Vickers hardness reaches ~170 HV0.2, and bending strength increases to 687.70 MPa for the as-built Al-22Si-0.2Fe-0.1Cu-Re alloys parts, which is much higher than that of cast counterparts. The formation mechanism of this fine microstructure and the enhancement reasons of bending strength are also discussed.

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