The study of the laser parameters and environment variables effect on mechanical properties of high compact parts elaborated by selective laser melting 316L powder
01 Nov 2013-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing (Elsevier)-Vol. 584, pp 21-31
TL;DR: In this article, a systematic analysis of the main parameters for the selective laser melting (SLM) of a commercial stainless steel 316L powder was conducted to improve the mechanical properties and dimensional accuracy of the fabricated parts.
Abstract: In this work, a systematic analysis of the main parameters for the selective laser melting (SLM) of a commercial stainless steel 316L powder was conducted to improve the mechanical properties and dimensional accuracy of the fabricated parts. First, the effects of the processing parameters, such as the laser beam scanning velocity, laser power, substrate condition and thickness of the powder layer, on the formation of single tracks for achieving a continuous melting and densification of the material were analysed. Then, the influence of the environmental conditions (gas nature) and of the preheating temperature on the density and dimensional accuracy of the parts was considered. The microstructural features of the SLM SS 316L parts were carefully observed to elucidate the melting-solidification mechanism and the thermal history, which are the basis of the manufacturing process. Finally, the mechanical properties of the corresponding material were also determined.
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TL;DR: A review of the emerging research on additive manufacturing of metallic materials is provided in this article, which provides a comprehensive overview of the physical processes and the underlying science of metallurgical structure and properties of the deposited parts.
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TL;DR: The potential of additive manufacturing to create alloys with unique microstructures and high performance for structural applications is demonstrated, with austenitic 316L stainless steels additively manufactured via a laser powder-bed-fusion technique exhibiting a combination of yield strength and tensile ductility that surpasses that of conventional 316L steels.
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TL;DR: In this article, the effects of laser power and scan speed on the thermal behavior of selective laser melting (SLM) additive manufacturing of AlSi10Mg powder were investigated.
547 citations
References
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TL;DR: In this article, the authors describe which types of laser-induced consolidation can be applied to what type of material, and demonstrate that although SLS/SLM can process polymers, metals, ceramics and composites, quite some limitations and problems cause the palette of applicable materials still to be limited.
1,241 citations
TL;DR: In this article, the effects of the processing parameters such as scanning speed and laser power on single tracks formation are explored, and a considerable negative correlation is found between the thermal conductivity of bulk material and the range of optimal scanning speed for the continuous single track sintering.
646 citations
TL;DR: Stainless steel has unique properties which can be taken advantage of in a wide variety of applications in the construction industry as mentioned in this paper, including its use in nuclear containment structures, thin-walled cladding and composite floor systems.
638 citations
25 Jul 2006-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this article, the densification and microstructural evolution during direct laser sintering of metal powders were studied, and it was found that when melting/solidification approach is the mechanism of sinter, the densifiers of metals powders (D ) can be expressed as an exponential function of laser specific energy input ( ψ ) as ln(1−− D )−= ǫ− Kψ.
Abstract: In the present work, the densification and microstructural evolution during direct laser sintering of metal powders were studied. Various ferrous powders including Fe, Fe–C, Fe–Cu, Fe–C–Cu–P, 316L stainless steel, and M2 high-speed steel were used. The empirical sintering rate data was related to the energy input of the laser beam according to the first order kinetics equation to establish a simple sintering model. The equation calculates the densification of metal powders during direct laser sintering process as a function of operating parameters including laser power, scan rate, layer thickness and scan line spacing. It was found that when melting/solidification approach is the mechanism of sintering, the densification of metals powders ( D ) can be expressed as an exponential function of laser specific energy input ( ψ ) as ln(1 − D ) = − Kψ . The coefficient K is designated as “densification coefficient”; a material dependent parameter that varies with chemical composition, powder particle size, and oxygen content of the powder material. The mechanism of particle bonding and microstructural features of the laser sintered powders are addressed.
537 citations