3D PRINTech

This Additive Manufacturing (AM) process produces metal parts layer by layer using a high energy laser beam to fuse metal powder particles. When each layer is complete, the build platform moves downward by the thickness of one layer, and a new powder layer is spread on the previous layer. While this process is able to produce quality parts and components, residual stress is a major problem during the fabrication process. That's because large temperature changes near the last melt spot - rapid heating and cooling - and the repetition of this process result in localized expansion and contraction, factors that cause residual stress. Residual stress (RS) Residual stresses are self-equilibrating stresses which remain in the part after its manufacture even without supplementary thermal gradient and external forces. These stresses arise from misfits in the shape of parts of both different regions and different phases within a part, or even because of local variations in elastic cons...

The polymer foam material refers to a microporous material based on a polymer (plastic, rubber, elastomer, or natural polymer material) with numerous bubbles inside, and can also be regarded as a composite material using gas as a filler. At present, polymer foam materials are mainly prepared by directly expanding and foaming the resin with a foaming agent. How to accurately control the micro-cell shape, the appearance and macro-foam structure are still a difficult problem. In order to solve some problems in the process of preparing polymer foam by direct expansion foaming method, Professor Jennifer A. Lewis and co-workers describe the fabrication of architected polymer foams by "direct bubble writing". In this process, bubbles are ejected into the air, deposited onto a substrate, and then photopolymerized with UV light, and open-and-closed-cell foams with locally graded densities can be printed into 3D objects such as 3D lattices, shells, and out-of-plane pillars.  The resea...

The 3D printing of food has been an evolving method of food production over recent years, and has allowed designers to combine their 3D digital design knowledge with food to produce shapes, textures, tastes, and forms that were previously found too challenging to create by hand, all whilst still being edible. 3D food printing  is able to make dishes from different pastes and materials, so it seems we are getting closer to the science-fiction concept. However, this time we are not in a sci-fi movie! Just look at the innovations already offered by different manufacturers who have all food printers that can make  chocolate ,  pasta , sugar, and even more dishes: the possibilities are almost unlimited. Current 3D food printers are designed to deposit small layers of material — think of a frosting dispenser except the ingredients are squeezed out, layer by layer, by a robotic arm. The latest models of 3D food printers are more complex and detailed. Examples of such device...