@article{cansizoglu_harrysson_west_cormier_mahale_2008, title={Applications of structural optimization in direct metal fabrication}, volume={14}, ISSN={["1355-2546"]}, DOI={10.1108/13552540810862082}, abstractNote={Purpose Optimization techniques can be used to design geometrically complex components with a wide variety of optimization criteria. However, such components have been very difficult and costly to produce. Layered fabrication technologies such as electron beam melting (EBM) open up new possibilities though. This paper seeks to investigate the integration of structural optimization and direct metal fabrication process. Design/methodology/approach Mesh structures were designed, and optimization problems were defined to improve structural performance. Finite element analysis code in conjunction with nonlinear optimization routines were used in MATLAB. Element data were extracted from an STL‐file, and output structures from the optimization routine were manufactured using an EBM machine. Original and optimized structures were tested and compared. Findings There were discrepancies between the performance of the theoretical structures and the physical EBM structures due to the layered fabrication approach. A scaling factor was developed to account for the effect of layering on the material properties. Practical implications Structural optimization can be used to improve the performance of a design, and direct fabrication technologies can be used to realise these structures. However, designers must realize that fabricated structures are not identical to idealized CAD structures, hence material properties much be adjusted accordingly. Originality/value Integration of structural optimization and direct metal fabrication was reported in the paper. It shows the process from design through manufacturing with integrated analysis.}, number={2}, journal={RAPID PROTOTYPING JOURNAL}, author={Cansizoglu, Omer and Harrysson, Ola L. A. and West, Harvey A., II and Cormier, Denis R. and Mahale, Tushar}, year={2008}, pages={114–122} }
@article{cansizoglu_harrysson_cormier_west_mahale_2008, title={Properties of Ti-6Al-4V non-stochastic lattice structures fabricated via electron beam melting}, volume={492}, ISSN={["0921-5093"]}, DOI={10.1016/j.msea.2008.04.002}, abstractNote={This paper addresses foams which are known as non-stochastic foams, lattice structures, or repeating open cell structure foams. The paper reports on preliminary research involving the design and fabrication of non-stochastic Ti–6Al–4V alloy structures using the electron beam melting (EBM) process. Non-stochastic structures of different cell sizes and densities were investigated. The structures were tested in compression and bending, and the results were compared to results from finite element analysis simulations. It was shown that the build angle and the build orientation affect the properties of the lattice structures. The average compressive strength of the lattice structures with a 10% relative density was 10 MPa, the flexural modulus was 200 MPa and the strength to density ration was 17. All the specimens were fabricated on the EBM A2 machine using a melt speed of 180 mm/s and a beam current of 2 mA. Future applications and FEA modeling were discussed in the paper.}, number={1-2}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, author={Cansizoglu, O. and Harrysson, O. and Cormier, D. and West, H. and Mahale, T.}, year={2008}, month={Sep}, pages={468–474} }