https://spiral.imperial.ac.uk/bitstream/10044/1/73026/9/1-s2.0-S0264127519306021-main.pdf

Review on design and structural optimisation in additive manufacturing: Towards next-generation lightweight structures

Influence of cell shape on mechanical properties of Ti-6Al-4V meshes fabricated by electron beam melting method.

Fabrication of polymeric lattice structures for optimum energy absorption using Multi Jet Fusion technology

Experimental study of fatigue crack growth behaviour in adhesively reinforced steel structures

Additive Manufacturing (AM) enables the production of geometrically complex parts that are difficult to manufacture by other means. However, conventional CAD systems are limited in the representation of such parts. This issue is exacerbated when lattice structures are combined or embedded within a complex geometry. This paper presents a computationally efficient, voxel-based method of generating lattices comprised of practically any cell type that can conform to an arbitrary external geometry. The method of conforming involves the tessellation and trimming of unit cells that can leave ‘hanging’ struts at the surface, which is a possible point of weakness in the structure. A method of joining these struts to form an external two dimensional lattice, termed a ‘net-skin’ is also described. Traditional methods of manufacturing lattice structures generally do not allow variation of cell properties within a structure; however, additive manufacturing enables graded lattices to be generated that are potentially more optimal. A method of functionally grading lattices is, therefore, also described to take advantage of this manufacturing capability.

https://cyberleninka.org/article/n/690165.pdf

A voxel-based method of constructing and skinning conformal and functionally graded lattice structures suitable for additive manufacturing

Comparison of fatigue crack retardation methods

Cell shape effect evaluation of polyamide cellular structures

Open-cell cellular structures have a high potential for use in automotive, railway, ship and aerospace industry as crash energy absorbers. This paper focuses on the influence of the second phase filler material as a way to further increase the capability of cellular material energy absorption. The behaviour of ductile (aluminium alloy) and brittle (polymer) cellular structures with regular topology with and without the pore filler (silicon rubber) under quasi-static and dynamic compressive loading conditions has been experimentally studied and evaluated. The base material properties of the aluminium alloy and the polymer were obtained with separate experimental testing. The use of second phase filler material resulted in significant changes in cellular material behaviour. It was observed that the pore filler material increases the capability of energy absorption and furthermore improves and stabilises the response of a brittle cellular structures.

Experimental Study of Open-Cell Cellular Structures with Elastic Filler Material

To investigate the applicability of infrared thermography as a tool for acquiring dynamic yielding in metals, a comparison of infrared thermography with three dimensional digital image correlation has been made. Dynamical tension tests and three point bending tests of aluminum alloys have been performed to evaluate results obtained by IR thermography in order to detect capabilities and limits for these two methods. Both approaches detect pastification zone migrations during the yielding process. The results of the tension test and three point bending test proved the validity of the IR approach as a method for evaluating the dynamic yielding process when used on complex structures such as cellular porous materials. The stability of the yielding process in the three point bending test, as contrary to the fluctuation of the plastification front in the tension test, is of great importance for the validation of numerical constitutive models. The research proved strong performance, robustness and reliability of the IR approach when used to evaluate yielding during dynamic loading processes, while the 3D DIC method proved to be superior in the low velocity loading regimes. This research based on two basic tests, proved the conclusions and suggestions presented in our previous research on porous materials where middle wave infrared thermography was applied.

Željko Domazet

Papers

Comparison of fatigue crack retardation methods

Cell shape effect evaluation of polyamide cellular structures

Experimental Study of Open-Cell Cellular Structures with Elastic Filler Material

Comparison of infrared and 3d digital image correlation techniques applied for mechanical testing of materials

Comparison of infrared and 3D digital image correlation techniques applied for mechanical testing of materials