Hasil untuk "Manufactures"

S. Pimenta, S. Pinho

Both environmental and economic factors have driven the development of recycling routes for the increasing amount of carbon fibre reinforced polymer (CFRP) waste generated. This paper presents a review of the current status and outlook of CFRP recycling operations, focusing on state-of-the-art fibre reclamation and re-manufacturing processes, and on the commercialisation and potential applications of recycled products. It is shown that several recycling and re-manufacturing processes are reaching a mature stage, with implementations at commercial scales in operation, production of recycled CFRPs having competitive structural performances, and demonstrator components having been manufactured. The major challenges for the sound establishment of a CFRP recycling industry and the development of markets for the recyclates are summarised; the potential for introducing recycled CFRPs in structural components is discussed, and likely promising applications are investigated.

N. Travitzky, A. Bonet, B. Dermeik et al.

Y. Wang, Yi-Shun Wang, Y. Yang

Askiner Gungor, Surendra M. Grupta

B. Beamon

M. Shahinpoor, K. Kim

H. Elmaraghy

P. Walstra, J. Wouters, T. Geurts

Heiko Gebauer, E. Fleisch, T. Friedli

David Cruller, D. Estrin, M. Srivastava

M. Groover

A. R. Crathorne, W. Shewhart

J. Kruth, M. Leu, T. Nakagawa

Hiroshige Masuo, Yuzo Tanaka, Shotaro Morokoshi et al.

Abstract The additive manufacturing (AM) is expected to be a promising manufacturing process for high strength or hard steels such as Ti-6Al-4V for the aerospace industry components having complex shapes. However, disadvantage or challenge of AM is presence of defects which are inevitably contained in the manufacturing process. This paper focuses on the effects of defects, surface roughness and Hot Isostatic Pressing (HIP) process on the fatigue strength of a Ti-6Al-4V manufactured by AM. Defects were mostly gas pores and those made by lack of fusion. Many defects which were formed at subsurface were eliminated by HIP and eventually HIP improved fatigue strength drastically to the level of the ideal fatigue limit to be expected from the hardness. Surface roughness had strong detrimental influence on fatigue strength. The method for estimating the effective size √areaeffmax of irregularly shaped defects and interacting adjacent defects was proposed from the viewpoint of fracture mechanics.

S. Saha, Dien Wang, V. Nguyen et al.

Speeding up submicrometer printing Using light to build three-dimensional structures with photopolymerization is the basis for two-photon lithography. However, there has been a trade-off between speed and resolution for fabricating structures with this method. Saha et al. optimize a new parallel printing methodology that relies on ultrafast lasers. They show the ability to dramatically increase the speed of printing while maintaining submicrometer resolution. Science, this issue p. 105 Femtosecond lasers can be used to print very thin 3D structures at ultrafast rates. High-throughput fabrication techniques for generating arbitrarily complex three-dimensional structures with nanoscale features are desirable across a broad range of applications. Two-photon lithography (TPL)–based submicrometer additive manufacturing is a promising candidate to fill this gap. However, the serial point-by-point writing scheme of TPL is too slow for many applications. Attempts at parallelization either do not have submicrometer resolution or cannot pattern complex structures. We overcome these difficulties by spatially and temporally focusing an ultrafast laser to implement a projection-based layer-by-layer parallelization. This increases the throughput up to three orders of magnitude and expands the geometric design space. We demonstrate this by printing, within single-digit millisecond time scales, nanowires with widths smaller than 175 nanometers over an area one million times larger than the cross-sectional area.

Abdul Moktadir, Towfique Rahman, Hafizur Rahman et al.

M. Leary, M. Mazur, J. Elambasseril et al.

Tomás Zegard, G. Paulino

R. Babiceanu, R. Seker

Georg Reischauer

We are witnessing an increasing adoption of digital technologies in manufacturing industries around the globe. This trend is often debated under the label Industry 4.0. A key claim put forward in these debates is that Industry 4.0 represents a revolution that will reshape manufacturing industries akin to previous industrial revolutions. Despite the popularity of this claim, it provides little help to clarify the identity of Industry 4.0. Such a clarification is however much needed given the worldwide proliferation of digital technologies in manufacturing industries. I address this gap by arguing to view Industry 4.0 as policy-driven innovation discourse in manufacturing industries that aims to institutionalize innovation systems that encompass business, academia, and politics. This clarification of the identity of Industry 4.0 adds to a better understanding of the relationship between manufacturing and politics as well as technological change in manufacturing.