Design Method for Inner Structure of Injection Mold Fabricated by Metal Laser Sintering

Fractal geometry can create virtual models of complex shapes as CAD data, and from these additive manufacturing can directly create physical models. The virtual-model-building capacity of fractal geometry and the physical-model-building capacity of additive manufacturing can be integrated to deal with the design and manufacturing of complex shapes. This study deals with the manufacture of fractal shapes using commercially available additive manufacturing facilities and 3D CAD packages. Particular interest is paid to building physical models of an IFS-created fractal after remodeling it for manufacturing. This article introduces three remodeling methodologies based on binary-grid, convex/concave-hull, and line-model techniques. The measurements of the manufactured fractal shapes are also reported, and the degree of accuracy that can be achieved by the currently available technology is shown.

Fractals and Additive Manufacturing

Ullah¹,

D’Addona²,

Harib³

et al. 2016

Anisotropic Stiffness Design for Mechanical Parts Fabricated by Multi-Material Additive Manufacturing

Tateno¹

2016

Stiffness is an important property of mechanical structures, particularly when it is necessary for a structure to contact other structures while in motion. In this study, we employed the advantages of additive manufacturing (AM) technology to create a multi-material structure and to investigate its stiffness properties. Herein, we also present an analytical model for designing a mechanical structure consisting of two-material, single-beam units, which was verified using a finite element simulation in our study. As an example, a two-material structure with the desired stiffness was fabricated using commercially available AM technology and employing both a soft material (natural rubber) and a hard material (acrylonitrile-butadiene-styrene resin, ABS).

Properties of Photopolymer Part with Aligned Short Ferromagnetic Fibers

Nakamoto¹,

Marukado²

2016

Photopolymer parts with short ferromagnetic fibers are fabricated by laser stereolithography. A magnetic field is applied to a liquid photopolymer that contains the short ferromagnetic fibers, with the axes of the short fibers aligned in the direction of the magnetic field. Then, the photopolymer is solidified with UV laser irradiation to get the desired shape. After fabricating the part, it is magnetized by applying magnetic field to it. When the magnetic field is applied in the direction of the aligned short fibers in the fabricated part, the residual magnetic flux density of the magnetized part in the direction of the aligned fibers becomes approximately twice that in the other directions. The magnetized part can be bent by applying an external magnetic field.