The Assembly Loads and Some Strengthening Methods of the Products from Porous Material with Coiled Wire

Abstract The product from porous permeable material based on a wire coil consists of a round, porous, thin-walled tube. The impact of assembly loads of the porous tube has been examined to determine the maximum values of the compressive force and axial elastic strain during the assembly. To improve mechanical properties of the product additional reinforcement has been proposed: larger diameter wire, woven wire cloth or spring.

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NICROBRAZ 50

Alloy Digest ◽

10.31399/asm.ad.ni0460 ◽

1994 ◽

Vol 43 (8) ◽

Keyword(s):

Corrosion Resistance ◽

Physical Properties ◽

Honeycomb Structures ◽

Thin Walled Tube ◽

Thin Walled ◽

Low Solubility

Abstract NICROBRAZ 50 is a low-melting, free-flowing filter metal for honeycomb structures and thin-walled tube assemblies. It has low solubility. This datasheet provides information on composition, physical properties, and hardness. It also includes information on corrosion resistance as well as joining. Filing Code: Ni-460. Producer or source: Wall Colmonoy Corporation.

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Optimal Design of the Shape of a Non-Ball Mandrel for Thin-Walled Tube Small Radius Cold Bending

Metals ◽

10.3390/met11081221 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1221

Author(s):

Lu Bai ◽

Jun Liu ◽

Ziang Wang ◽

Shuanggui Zou

Keyword(s):

Ideal Point ◽

Small Radius ◽

Grey Wolf Optimizer ◽

Forming Quality ◽

Hollow Section ◽

Cold Bending ◽

Bending Process ◽

Before And After ◽

Thin Walled Tube ◽

Thin Walled

In the field of cold bending, it is necessary to use ball mandrels, especially to bend thin-walled tubes with a small radius. However, the bending process with a ball mandrel is complex and expensive, and it is easy to jam the core ball inside the tube. To solve these issues, we designed two kinds of hollow non-ball mandrel schemes with low stiffness that were suitable for the small radius bending of thin-walled tubes. We evaluated the forming quality of cold bending numerically and the influence of the hollow section length and thickness on the forming indices. Our results showed that the thickness of the hollow section has a greater influence on forming quality than the length. As the hollow section’s thickness increased, the wrinkling rate first declined by approximately 40% and then increased by above 50%. When the thickness was 11 mm in scheme 1 and 13 mm in scheme 2, the wrinkling rate reached minimum values of 1.32% and 1.50%, respectively. As the hollow section’s thickness increased, the flattening rate decreased by more than 60% and the thinning rate increased by about 40%. A multi-objective optimization of forming indices was carried out by ideal point method and grey wolf optimizer. By comparing the forming results before and after optimization, the feasibility of using the proposed hollow mandrel was proved, and the hollow mandrel scheme of standard cylinder is therefore recommended.

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Cold Forging Effect on the Microstructure of Motorbike Shock Absorbers Fabricated by Tube Forming in a Closed Die

Applied Sciences ◽

10.3390/app11052142 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2142

Author(s):

Trung-Kien Le ◽

Tuan-Anh Bui

Keyword(s):

Material Flow ◽

Cold Forging ◽

Technological Parameters ◽

Forming Process ◽

Tube Forming ◽

Shock Absorbers ◽

Thin Walled Tube ◽

Thin Walled ◽

Quality Of Products ◽

Forming Defects

Motorbike shock absorbers made with a closed die employ a tube-forming process that is more sensitive than that of a solid billet, because the tube is usually too thin-walled to conserve material. During tube forming, defects such as folding and cracking occur due to unstable tube forming and abnormal material flow. It is therefore essential to understand the relationship between the appearance of defects and the number of forming steps to optimize technological parameters. Based on both finite element method (FEM) simulations and microstructural observations, we demonstrate the important role of the number and methodology of the forming steps on the material flow, defects, and metal fiber anisotropy of motorbike shock absorbers formed from a thin-walled tube. We find limits of the thickness and height ratios of the tube that must be held in order to avoid defects. Our study provides an important guide to workpiece and processing design that can improve the forming quality of products using tube forming.

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Energy absorbed ability and damage analysis for honeycomb sandwich material of bio-inspired micro aerial vehicle under low velocity impact

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406220975427 ◽

2020 ◽

pp. 095440622097542

Author(s):

Jianxun Du ◽

Peng Hao ◽

Mabao Liu ◽

Rui Xue ◽

Lin’an Li

Keyword(s):

Honeycomb Structure ◽

Low Velocity Impact ◽

Parameter Study ◽

Low Velocity ◽

Micro Aerial Vehicle ◽

Thin Walled Structures ◽

Wide Range ◽

Aerial Vehicle ◽

Thin Walled ◽

The Impact

Because of the advantages of light weight, small size, and good maneuverability, the bio-inspired micro aerial vehicle has a wide range of application prospects and development potential in military and civil areas, and has become one of the research hotspots in the future aviation field. The beetle’s elytra possess high strength and provide the protection of the abdomen while being functional to guarantee its flight performance. In this study, the internal microstructure of beetle’s elytra was observed by scanning electron microscope (SEM), and a variety of bionic thin-walled structures were proposed and modelled. The energy absorption characteristics and protective performance of different configurations of thin-walled structures with hollow columns under impact loading was analyzed by finite element method. The parameter study was carried out to show the influence of the velocity of impactor, the impact angle of the impactor and the wall thickness of honeycomb structure. This study provides an important inspiration for the design of the protective structure of the micro aerial vehicle.

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A top-down approach making cellulose carbonaceous aerogel/MnO2 ultrathick bulk electrodes with high mass loading for supercapacitors

Materials Chemistry Frontiers ◽

10.1039/d1qm00286d ◽

2021 ◽

Author(s):

Weiye Zhang ◽

Yanchen Li ◽

Beibei Wang ◽

Jingmeng Sun ◽

Lin Lin ◽

...

Keyword(s):

Porous Carbon ◽

High Mass ◽

Mass Loading ◽

Top Down ◽

Thin Walled Tube ◽

Natural Wood ◽

Thin Walled ◽

Array Structure

A cellulose carbonaceous aerogel/MnO2 ultrathick electrode with a unique low curvature, porous carbon thin-walled tube array structure was obtained from natural wood using a simple top-down approach.

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