Additive manufacturing of metallic components – Process, structure and properties

Additive manufacturing of metals

MUCKE aims to mine a large volume of images, to structure them conceptually and to use this conceptual structuring in order to improve large-scale image retrieval. The last decade witnessed important progress concerning low-level image representations. However, there are a number problems which need to be solved in order to unleash the full potential of image mining in applications. The central problem with low-level representations is the mismatch between them and the human interpretation of image content. This problem can be instantiated, for instance, by the incapability of existing descriptors to capture spatial relationships between the concepts represented or by their incapability to convey an explanation of why two images are similar in a content-based image retrieval framework. We start by assessing existing local descriptors for image classification and by proposing to use co-occurrence matrices to better capture spatial relationships in images. The main focus in MUCKE is on cleaning large scale Web image corpora and on proposing image representations which are closer to the human interpretation of images. Consequently, we introduce methods which tackle these two problems and compare results to state of the art methods. Note: some aspects of this deliverable are withheld at this time as they are pending review. Please contact the authors for a preview.

http://ieeexplore.ieee.org/iel2/4524/12820/00592460.pdf

Image Processing

A review on selective laser sintering/melting (SLS/SLM) of aluminium alloy powders: Processing, microstructure, and properties

This article reviews published data on the mechanical properties of additively manufactured metallic materials. The additive manufacturing techniques utilized to generate samples covered in this review include powder bed fusion (e.g., EBM, SLM, DMLS) and directed energy deposition (e.g., LENS, EBF3). Although only a limited number of metallic alloy systems are currently available for additive manufacturing (e.g., Ti-6Al-4V, TiAl, stainless steel, Inconel 625/718, and Al-Si-10Mg), the bulk of the published mechanical properties information has been generated on Ti-6Al-4V. However, summary tables for published mechanical properties and/or key figures are included for each of the alloys listed above, grouped by the additive technique used to generate the data. Published values for mechanical properties obtained from hardness, tension/compression, fracture toughness, fatigue crack growth, and high cycle fatigue are included for as-built, heat-treated, and/or HIP conditions, when available. The effects of test...

Metal Additive Manufacturing: A Review of Mechanical Properties

https://research.birmingham.ac.uk/portal/files/19592544/NR_mod_CL31_12_9_14_F4.pdf

Selective laser melting of AlSi10Mg alloy: Process optimisation and mechanical properties development

Selective laser melting of AlSi10Mg: Influence of post-processing on the microstructural and tensile properties development

The main challenge associated with the application of selective laser melting (SLM) to Ni based superalloys is the performance of process optimisation to maximise the mechanical properties. The energy density parameter has typically been used as a semiquantitative approach to identify the energy threshold beyond which the material achieves virtually full consolidation. Nonetheless, some Ni superalloys are susceptible to crack formation during SLM, which cannot be avoided via process optimisation. In the present report, a comparative study is presented showing the utility of the energy density parameter in process optimisation for γ′ and γ′/γ″ strengthened Ni based superalloys. For both classes, it was found that the build density increases [i.e. void area (%) decreases] with the increase in the energy density. Nonetheless, no direct correlation can be found between the energy density parameter and the cracking density.

Process optimisation of selective laser melting using energy density model for nickel based superalloys

https://www.research.manchester.ac.uk/portal/files/82081989/Larrosa_etal_TAFMEC_2018_303_Non_MARKED.pdf

N. Read

Papers

Selective laser melting of AlSi10Mg alloy: Process optimisation and mechanical properties development

Selective laser melting of AlSi10Mg: Influence of post-processing on the microstructural and tensile properties development

Process optimisation of selective laser melting using energy density model for nickel based superalloys

Linking microstructure and processing defects to mechanical properties of selectively laser melted AlSi10Mg alloy

Defect Formation and its Mitigation in Selective Laser Melting of High γ′ Ni‐Base Superalloys