scholarly journals Influence of Weakening Groove on Cutting Results of Composites Subjected to Shaped Charge Jet

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Mingfa Ren ◽  
Fei Weng ◽  
Jing Sun ◽  
Ke Tang ◽  
Lina Feng ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Weight Ratio ◽  
High Strength ◽  
Shaped Charge ◽  
Three Dimensional Model ◽  
Element Analysis ◽  
Cutting Test ◽  
Cfrp Composites ◽  
Separation Devices ◽  
Shaped Charge Jet

Carbon-fiber-reinforced polymer (CFRP) has been widely used in aerospace structures for its high strength to weight ratio and high stiffness to weight ratio. However, current pyrotechnic separation devices are mainly made of metal materials, the cutting research on CFRP composites is limited, and the effect of weakening groove on cutting results of composites is unclear under the action of shaped charge jet. In this paper, there firstly established a three-dimensional model of explosive cutting of CFRP composites by nonlinear finite element analysis (FEA), and based on the separation time, delamination, and kinetic energy of the laminate, the influence of weakening grooves on cutting results to the laminate is discussed. The results show that, in contrast to laminates with weakening grooves, laminates without weakening grooves increase the delamination of laminates. At the same time, here, we carried out the explosive cutting test on CFRP composites to verify the rationality of the simulation model. In addition, in order to obtain a better model under the action of shaped charge jet, we optimized the width and height of weakening groove by simulation calculation. Therefore, it proves that this study can guide the application of CFRP composites subjected to shaped charge jet in aerospace separation engineering.

Benefits of Using Diamond Dies for Cold Alternate Drawing of Magnesium Alloys

2016 ◽  
Vol 716 ◽  
pp. 13-21 ◽  
Author(s):  
Vladimir Stefanov Hristov ◽  
Kazunari Yoshida
Keyword(s):  
Magnesium Alloy ◽  
Weight Ratio ◽  
High Strength ◽  
Wire Drawing ◽  
High Ductility ◽  
Element Analysis ◽  
The Wire ◽  
Shearing Strain ◽  
Drawing Method

In recent years, due to its low density and high strength/weight ratio, magnesium alloy wires has been considered for application in many fields, such as welding, electronics, medical field (for production of stents). But for those purposes, we need to acquire wires with high strength and ductility. For that we purpose we proposed alternate drawing method, which is supposed to highly decrease the shearing strain near the surface of the wire after drawing, by changing the direction of the wire drawing with each pass and thus acquiring high ductility wires.We have done research on the cold alternate drawing of magnesium alloy wires, by conducting wire drawing of several magnesium wires and testing their strength, hardness, structure, surface and also finite element analysis, we have proven the increase of ductility at the expense of some strength.In this research we are looking to further improve the quality of the drawn wires by examining the benefits of using diamond dies over tungsten carbine dies. Using the alternate drawing method reduces the strength of the drawn wires and thus lowering their drawing limit. By using diamond dies we are aiming to decrease the drawing stress and further increase the drawing limit of the alternate drawn wires and also improve the quality of the finishing surface of the wires. With this in mind we are aiming to produce a good quality wire with low diameter, high ductility, high strength and fine wire surface.

A Novel Packing Hollow Dodecahedron Model to Study the Mechanical and Thermal Properties of Stocastic Metallic Foams

2021 ◽  
Author(s):  
Rui Dai ◽  
Beomjin Kwon ◽  
Qiong Nian
Keyword(s):  
Thermal Properties ◽  
Physical Properties ◽  
Three Dimensional ◽  
Weight Ratio ◽  
High Strength ◽  
Specific Area ◽  
Deposition Process ◽  
Metallic Foam ◽  
Thermal Testing ◽  
Mechanical And Thermal Properties

Abstract Stochastic foam with hierarchy order pore structure possesses distinguished physical properties such as high strength to weight ratio, super lightweight, and extremely large specific area. These exceptional properties make stochastic foam as a competitive material for versatile applications e.g., heat exchangers, battery electrodes, automotive components, magnetic shielding, catalyst devices and etc. Recently, the more advanced hollow cellular (shellular) architectures with well-developed structure connections are studied and expected to surpass the solid micro/nanolattices. However, in terms of theoretical predicting and studying of the cellular foam architecture, currently no systematic model can be utilized to accurately capture both of its mechanical and thermal properties especially with hollow struts due to complexity induced by its stochastic and highly reticulate nature. Herein, for the first time, a novel packing three-dimensional (3D) hollow dodecahedron (HPD) model is proposed to simulate the cellular architecture. An electrochemical deposition process is utilized to manufacture the metallic foam with hollow struts. Mechanical and thermal testing of the as-manufactured foams are carried out to compare with the HPD model. HPD model is proved to accurately capture both the topology and the physical properties of stochastic foam at the similar relative density. Particularly, the proposed model makes it possible to readily access and track the physical behavior of stochastic foam architecture. Accordingly, this work will also offer inspiration for designing an efficient foam for specific applications.

Finite-element analysis of multi-body contacts for pile driving using a hydraulic pile hammer

2011 ◽  
Vol 225 (5) ◽  
pp. 1153-1161 ◽  
Author(s):  
Y Guo ◽  
J P Hu ◽  
L Y Zhang
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Test Point ◽  
Pile Driving ◽  
Penalty Function Method ◽  
Three Dimensional Model ◽  
Element Analysis ◽  
Material Choice ◽  
Multi Body ◽  
The Impact

This article treats the pile driving as multi-body dynamic contacts. By using the penalty function method and three-dimensional model of finite-element method, the dynamic process of pile driving is acquired and a method for choosing the cushion material of the hydraulic pile hammer to improve driving efficiency is proposed. The process of pile driving in the real situation of an industrial experiment is simulated. The results of stress on test point are consistent with the test point. By analysing the stress distributed along the direction of pile radius and pile axis, the rule of the stress distribution on the pile is concluded. The rule for cushion material choice is obtained by comparing the influence for the impact stress with different elastic modulus ratio of the hammer cushion to the pile and the pile cushion to the pile.

Analysis and Research of High Speed Milling of Thin-Walled Bracket Part Based on UG NX

2010 ◽  
Vol 129-131 ◽  
pp. 256-260
Author(s):  
Yi Shu Hao ◽  
Chuang Hai ◽  
Xin Xing Zhu
Keyword(s):  
High Speed ◽  
Three Dimensional ◽  
Structural Features ◽  
Milling Process ◽  
Analysis Method ◽  
Three Dimensional Model ◽  
Machining Processes ◽  
Element Analysis ◽  
High Speed Milling ◽  
Tool Paths

Treating high speed milling theory as the guidance, this paper researched high speed milling process of bracket part based on UG NX. Combined with the structural features of bracket part, three dimensional model is built by UG NX CAD and machining processes are worked out after analysis. UG CAM module was applied to fabricate tool paths. At last, finite element analysis method is introduced to study the processing deformation by UG NX NASTRAN module, based on which measures to restrain processing deformations is advanced and processing sequences are optimized.

Finite Element Analysis of Load Capacity on Coupling Clamps for Pipe

2012 ◽  
Vol 201-202 ◽  
pp. 741-744 ◽  
Author(s):  
Zhen Ning Hou ◽  
Jun Wu ◽  
Qing Wang ◽  
Hong Gen Tian ◽  
Nan Chao ◽  
...  
Keyword(s):  
Finite Element ◽  
Stress Intensity ◽  
Optimization Design ◽  
Load Capacity ◽  
Three Dimensional ◽  
Process Conditions ◽  
Fe Model ◽  
Three Dimensional Model ◽  
Element Analysis ◽  
Element Approach

A finite element approach based on Ansys is developed to simulate stress intensity distribution in a three dimensional model of coupling clamp joint, which includes ferrules, pipe caps and bolts. The characteristics of stress intensity distributions of coupling clamp joint under strength pressure loading have been studied by means of the non-linear finite element method. The FE model can also predict the clamp quality and tolerances to be expected under different process conditions and define the most effective process parameters to influence the tolerances. The study could give us a better understanding on the mechanism and basis for optimization design of the coupling clamp joint.

Study on the Complete Equivalent Initial Imperfection of High Formwork Supporting Frame with Pulley-Clip Style

2011 ◽  
Vol 368-373 ◽  
pp. 3052-3056
Author(s):  
Wei Jun Yang ◽  
Yong Da Yang
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Initial Imperfection ◽  
Influential Factors ◽  
Horizontal Load ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Element Analysis ◽  
Finite Element Software ◽  
Supporting Frame

New full hall scaffolds with pulley-clip style formwork support system is adopted in the concert hall of Changsha. This paper presents the concept of the complete equivalent initial imperfection according to the characteristics of too many influential factors on the high formwork supporting frame，then makes the complete equivalent initial imperfectione equivalent to assumed equivalent horizontal load in order to ensure the safety of the frame. At the same time, it gets a three-dimensional model by the general finite element software ANSYS 10.0. Based on the results of experiment and finite element analysis, it gets the recommended value of assumed equivalent horizontal load. The study on the high formwork supporting frame with pulley-clip style provides some reference for other similar projects.

scholarly journals Development and Verification of Three-Dimensional Model of Femoral Bone: Finite Element Analysis

2019 ◽  
Vol 1372 ◽  
pp. 012014 ◽  
Author(s):  
Aishah Umairah Abd Aziz ◽  
Hong Seng Gan ◽  
Ahmad Kafrawi Nasution ◽  
Mohammed Rafiq Abdul Kadir ◽  
Muhammad Hanif Ramlee
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Three Dimensional ◽  
Femoral Bone ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Element Analysis

scholarly journals Geometrical behavior of laminated graphite/epoxy composite using hypermesh

2018 ◽  
Vol 7 (2.20) ◽  
pp. 214
Author(s):  
Ch Siva RamaKrishna ◽  
KV Subba Rao ◽  
Saineelkamal Arji
Keyword(s):  
Residual Stresses ◽  
Epoxy Composite ◽  
Weight Ratio ◽  
Laminated Composite ◽  
High Strength ◽  
Element Analysis ◽  
Aspect Ratios ◽  
Military Applications ◽  
Inherent Strength

The laminated composite material is  made of ply which are specically used in automotive, aerospace and military applications due to less in weight and high strength to weight ratio. The role of structural strength is very important in composites, as the material is weak in inherent strength leads to damage of equipment made with the laminated composite. Hence, an accurate understanding of their structural geometrical behavior for residual stresses is required, such as residual stresses with different aspect ratios. In present work, various aspect ratios of laminated composite and its residual stresses are investigated using finite element analysis. The numerical results showed, on the residual stresses, that the effects the change the residual stresses due change of aspect ratio of laminated Graphite/epoxy composite. 

Surface Grinding of CFRP Composites Using Rotary Ultrasonic Machining: Effects of Ultrasonic Power

2017 ◽  
Author(s):  
Hui Wang ◽  
Yingbin Hu ◽  
Fuda Ning ◽  
Yuzhou Li ◽  
Meng Zhang ◽  
...  
Keyword(s):  
Cutting Force ◽  
Weight Ratio ◽  
High Strength ◽  
Surface Grinding ◽  
Future Research ◽  
Ultrasonic Power ◽  
Ultrasonic Machining ◽  
Rotary Ultrasonic Machining ◽  
Grinding Processes ◽  
Cfrp Composites

Carbon fiber reinforced plastic (CFRP) composites have superior properties, including high strength-to-weight ratio, high modulus-to-weight ratio, high fatigue resistance, etc. These properties make CFRP composites being popular in many kinds of industries. Due to the inhomogeneous and anisotropic properties, and high abrasiveness of the reinforcement in CFRP composites, they are classified as difficult-to-cut materials in surface grinding processes. Many problems (including high cutting force and low machining efficiency) are generated in conventional surface grinding processes. In order to reduce and eliminate these problems, rotary ultrasonic machining (RUM) surface grinding of CFRP composites is conducted in this investigation. Effects of ultrasonic power in different machining levels are of great importance in RUM surface grinding processes. However, no investigations on effects of ultrasonic power in different machining levels are conducted in such a process. This investigation, for the first time, tests the effects of ultrasonic power on output variables, including cutting force, torque, and surface roughness in different machining levels. This paper will provide guides for future research on effects of ultrasonic power in different combinations of machining variables on output variables.

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