3D printer is a manufacturing method which builds layer upon layer and is in contrast to conventional manufacturing methods. This manufacturing method has the potential to significantly change the way of manufacturing and brings various advantages. In the past, since 3D printer was technically at an early stage, it was referred as Rapid Prototyping and was used only for prototype to confirm the shape. However, today, with technical enhancements, the usage is spreading from functional prototype, production tools such as jigs, to end use parts production. This paper includes case studies at Ricoh. Furthermore, this paper describes the possibility that 3D printer can change way of manufacturing and its limitations. The specific examples introduced in this paper focus on polymer.
Para rubber tree, the current source of natural rubber is susceptible to disease and has a history of extinction. To make natural rubber a sustainable product, number of efforts are underway to obtain alternative sources of natural rubber. Guayule and Russian dandelion are currently the two strong candidates. Study on guayule, a bush that grows in an arid area has been on and off for many decades. The prohibitive cost of processing rubber always discouraged continuous effort. In 2014, an environmentally friendly pilot plant using solvent extraction technology was built at the outskirt of Mesa, Arizona, with a nearby 280-acre farm. The new facility will not only significantly improve productivity of rubber manufacturing, but also physical properties are equivalent to the current source, para rubber. Another alternative source of natural rubber, Russian dandelion, a weed that grows in a temperate climate was also discussed.
It is increasingly difficult to solve social problems using fragmented knowledge when our environment is constantly fluctuating, the future is unpredictable and people have diverse, often contrasting values. When tackling issues, it is desirable to keep an open mind and incorporate the perspectives of others, not bound by the assumptions and traditional culture of each discipline. This review discusses how science and technology can be integrated with other fields to generate more creative questions and solutions, and what theoretical discussions prevail around such transdisciplinary practice. It introduces the notions of science communication, which aims to produce a dialogue between scientists/engineers and the lay public, and STEAM education and thinking, which view scientific and technological knowledge as continuous to that of other disciplines and ways of thinking. The author also discusses the mechanism of science and technology as social symbols from the perspective of semiotics and translation studies, looking at how rubber and latex are interpreted beyond their functions, using the fashion and media scenes as examples.
In this final Part 6, the Author proposes a new theory of rubber wear connected with rubber friction through abrasion pattern formation generated by stick-slip motion. The kinetic interpretation was introduced to explain the close relationship between the wear rate and the distance of abrasion patterns named the wear-abrasion pattern diagram, which showed that two mechanisms work differently at an initial stage and a final stage of the abrasion pattern formation. After the inspection of the theory of rubber wear given by AG. Thomas theoretically and experimentally, the author proposes a new theory of the rubber wear based on the fracture mechanics treatment, where is shown that the stick-slip motion is the direct driving force to promote the rubber wear, and thus the abrasion pattern of the same length as the period of the stick-slip motion is left on the wear surface of the rubber.
Many companies use molds to perform vulcanization molding of rubber. The unvulcanized rubber compound, which has been kneaded, mixed, and preformed, is loaded on the mold, and then mold vulcanization molding is applied using a compression molding machines, an injection molding vulcanization machines, and a transfer molding machines. Mold vulcanization molding, which uses a mold, involves vulcanization reaction (cross-linking reaction) and molding under high temperature and high pressure, and the goodness or badness of the resulting molded product is determined by the compound design, the accuracy of the mold, the goodness or badness of the mold, and the vulcanization molding conditions. In this section, this paper discusses the history of rubber molding, the cancellation of the technology of rubber molding and the trends to be discussed.