Development Of Light Materials Research Articles

Análise das superfícies de saída e de folga de ferramentas de corte empregadas no torneamento de ferro fundido cinzento perlítico com diferentes adições de nióbio

Cast iron corresponds to the second most used metallic material worldwide. However, its production has shown reductions, mainly due to the development of lighter materials. In this sense, metallurgical efforts have been made to add elements to obtain different solid solutions that would lead to the improvement and guarantee of the diversity of this alloy. However, modifications of any kind to the properties of a material have an impact on its machinability. Thus, this work aimed to evaluate the influence of the addition of niobium (0.21-0.24% by weight) in a pearlitic gray cast iron alloy (equivalent to the EN-GJL-250 class) on the wear of the tools of cemented carbide (class K20) during the turning. The wear on the rake and clearance surfaces was qualitatively evaluated via scanning electron microscopy (SEM) and X-ray dispersive energy spectroscopy (EDS). Together, the chemical composition variation occurred with the chip breaker geometry: tools with chip breaker (GH) or without chip breaker (Flat Top). All these variations were indifferent in relation to the wear of the tools and their mechanisms. Regardless of the chemical composition, material of the machined part was found adhered to both the rake surface and the clearance of all cutting tools. In addition, grooves were found in the flank, suggesting the abrasion mechanism.

Bio-inspirations for the Development of Light Materials based on the Nanomechanical Properties and Microstructures of Beetle Dynastes tityus

Dynastes tityus (D. tityus) is a typical beetle whose elytra are light and strong. The primary function of elytra is to protect beetle’s hindwings. In this paper, D. tityus elytra were selected as the biological prototype for the investigation to obtain bio-inspirations for the design and development of light materials with high ratio of strength to mass. Firstly, the microstructure investigation and quasi-static nanoindentation tests have been carried out on the ten samples of the selected elytra of D. tityus to reveal their mechanical properties and microstructures. Secondly, based on the findings from the microstructure investigation and nanoindentation tests, three models of bio-inspired materials have been proposed for further study to gain the deep understanding of the relationships between the special mechanical characteristics and microstructures. Then Finite Element Analysis (FEA) simulations have been performed on the three models for harvesting the bio-inspirations for the initial design of light materials. Finally, through comparative analysis of the findings from the microstructure investigation, the nanoindentation tests and the simulations, some meaningful bio-inspirations have been reaped for the future optimization of the design and development of light materials with high ratio of strength to mass.

On the adaptability of 1/1 cubic approximant structure in the Mg–Al–Zn system with the particular example of Mg32Al12Zn37

Intermetallic Mg alloys are of interest in the development of light materials with specific properties and some of them are crystalline approximants of quasicrystalline materials. Mg32Al12Zn37 single crystal structure, cubic, Im3¯, a = 14.1845(1) Å, is disordered and belongs to the well known 1/1 approximant structural type commonly called Mg32(Al1−xZnx)49 or T-phase. In this family, Mg32Al12Zn37 is a new member remarkable for its very special composition nearby intersection of the 2/1 and 1/1 lines that mark composition domains of cubic 2/1 and 1/1 approximants. Structural features are discussed comparatively with literature data to emphasize the great adaptability through atom disorder of the 1/1 structure.

製紙スラッジを用いた植栽用軽量資材の開発

製紙スラッジを用いた植栽用軽量資材の開発

Perspectives for Nanostructured Light Metals and Alloys

Nano-structured metals have attracted growing research interest, which has brought about the development of methods for their fabrication. A number of fabrication methods involve severe plastic deformation, SPD, and involve refinement of the coarse-grained structures to grain sizes on a nanometre scale. Such grain refinement is accompanied by a significant improvement in mechanical strength. The improved properties of the nano-structured metals open up perspectives for their application in innovative industries such as aerospace, surface transport and biomedical implant manufacturing. The advantage of using nano-structured light metals is possible weight reduction of manufactured components. In the case of automotive parts, this may contribute to a reduction in CO2 emissions – one of the most important global challenges – due to the significantly higher strength of nano-structured metals and alloys compared to their microcrystalline counterparts. Nano-structured metals also exhibit high strain rate superplasticity at relatively low temperatures. This offers fast processing of materials, whose superplastic forming would be restricted otherwise. Finally, nano-structured metals also possess improved functional properties such as wear and corrosion resistance, which can broaden the range of applications of engineering metals and alloys even further. This paper reviews recent progress in the development of light nano-engineered metals and alloys. In particular, interest is concentrated on the metals and alloys processed by SPD methods. Conclusions are drawn with regard to future development of light materials for application in transport.

Material ambitions [aerospace manufacturing

The author writes about global aircraft makers that are vying for pole position in the development of lighter materials for their planes.