Investigation on the Punching Quality of Hybrid Impact Hydroforming

2014 ◽  
Vol 602-605 ◽  
pp. 520-523 ◽  
Author(s):  
Shao Hua Wang ◽  
Li Hui Lang ◽  
Li Jing Lin
Keyword(s):  
Shock Wave ◽  
High Energy ◽  
Stress Effects ◽  
Depth Direction ◽  
Forming Technology ◽  
Element Simulation ◽  
Shock Wave Generation ◽  
Width Direction ◽  
Short Time

High energy forming technology has been widely applied in the aircraft and automobile area which means high energy works in very short time, no more than 1s. The innovative hybrid impact hydro-forming (IHF) technology is a kind of high energy forming technique. It combines hydroforming and high energy forming, which first use hydro-forming to shape large character of product, then use high energy to form small features, such as convex tables, bars etc. The present work investigates the shock wave generation of hybrid impact hydroforming. In this paper, the theory of shock wave is presented and finite element simulation was carried out by using MSC. The pressure distribution changes in the depth direction, but not in the width direction. Using this shock wave loading condition we did forming experiments. Punching occurred as a result of combined tensile and shear stress effects. Furthermore, the design precise of die and clearance between punch and die may less strict. Therefore, the research is very useful for the development and application of hybrid impact hydroforming.

Investigation on the Effect of Liquid Hammer Geometry to the Pressure Distribution of Innovative Hybrid Impact Hydroforming

2014 ◽  
Vol 941-944 ◽  
pp. 1843-1849 ◽  
Author(s):  
Murhaf Marai ◽  
Li Hui Lang ◽  
Shao Hua Wang ◽  
Li Jin Lin ◽  
Chun Lei Yang ◽  
...  
Keyword(s):  
Loading Condition ◽  
Experimental Approach ◽  
High Energy ◽  
Geometrical Shape ◽  
Wave Loading ◽  
Forming Process ◽  
Short Time ◽  
The Impact ◽  
Complex Parts

The innovative hybrid impact hydroforming (IHF) technology is a kind of high energy forming technique which can be used for forming complex parts with small features, such as convex tables, bars etc. which are widely employed in automotive and aircraft industries. The impact hydroforming technology means the most features are formed by hydroforming and the small features are rapidly reshaped by high intensity impact energy in a very short time after the traditional hydroforming. The impact pressure rises to the peak in 10ms which belongs to dynamic loading. The present work investigates IHF using a numerical /experimental approach. Finite element simulations using MSC.Patran were carried out changing the geometrical shape of liquid hammer.. Using this shock wave loading condition we did forming experiments. During forming process, stress distribution in the blank is comparatively better as compared with traditional methods so possibility of fracture is reduced. Inertia is also an important factor which affects control quality. Therefore, the research is very useful for improving forming quality of complicated products. It will be widely applied in automotive and aircraft industries.

Design an Effective Solution for Stretch Forming of Sheet Metal with a Shorter Free Edge

2013 ◽  
Vol 395-396 ◽  
pp. 941-944
Author(s):  
Qi Gang Han ◽  
Qiang Zhang ◽  
Ming Zhe Li ◽  
Shi Zhong Su ◽  
Wen Ke Yang ◽  
...  
Keyword(s):  
Finite Element ◽  
High Speed ◽  
Free Edge ◽  
Effective Solution ◽  
High Speed Train ◽  
Stretch Forming ◽  
High Quality ◽  
Forming Technology ◽  
Element Simulation

To remove the disadvantage of conventional stretch forming machine (CSFM), a flexible stretch forming machine (FSFM) has been developed by authors recently. Based on finite element simulation and experiments, the advantages of FSFM have been detailed discussed. Our results indicated that the discrete multi-gripping jaws can swing and rotate in any direction automatically, which can solve the wasteful production of CSFM by increase the rate of materials utilization and close-fitting dies. Furthermore, the value of springback and thickness gradient in the parts formed by discrete multi-gripping jaws is smaller compare with that of integrally gripping jaws, which can help to achieve a high quality of stretch forming parts. A series of double-curved sheet panels have been formed by FSFM easily and used in the cabinet covers of high-speed train and the Dongdaemun Design Park building successfully. This work has a strong value in enhance the way to flexible and reproducible stretch forming technology.

Electron microscopy study of shock synthesis of silicides

1993 ◽  
Vol 51 ◽  
pp. 1162-1163
Author(s):  
Kenneth S. Vecchio
Keyword(s):  
Shock Wave ◽  
Plastic Deformation ◽  
Close Contact ◽  
Microscopy Study ◽  
High Energy ◽  
Electron Microscopy Study ◽  
Powder Materials ◽  
Porous Powder ◽  
Wave Effects ◽  
Wave Passage

Shock-induced reactions (or shock synthesis) have been studied since the 1960’s but are still poorly understood, partly due to the fact that the reaction kinetics are very fast making experimental analysis of the reaction difficult. Shock synthesis is closely related to combustion synthesis, and occurs in the same systems that undergo exothermic gasless combustion reactions. The thermite reaction (Fe2O3 + 2Al -> 2Fe + Al2O3) is prototypical of this class of reactions. The effects of shock-wave passage through porous (powder) materials are complex, because intense and non-uniform plastic deformation is coupled with the shock-wave effects. Thus, the particle interiors experience primarily the effects of shock waves, while the surfaces undergo intense plastic deformation which can often result in interfacial melting. Shock synthesis of compounds from powders is triggered by the extraordinarily high energy deposition rate at the surfaces of the powders, forcing them in close contact, activating them by introducing defects, and heating them close to or even above their melting temperatures.

ANALISIS VISUAL PADA SAMPUL DEPAN MAJALAH DESAIN GRAFIS “CONCEPT” EDISI ULTAH PERDANA (Sebuah Kajian Semiotika)

DeKaVe ◽  
2013 ◽  
Vol 1 (2) ◽  
Author(s):  
Prayanto WH
Keyword(s):  
Graphic Design ◽  
Roland Barthes ◽  
Specific Design ◽  
Design Work ◽  
Design Elements ◽  
Semiotic Approach ◽  
Short Time ◽  
Content Information ◽  
Magazine Cover

Magazine is one of the forms of mass media that has fungsikomunikasi to convey information to mass audiences. The cover is an important element because it is through cover / cover one can guess the contents of the magazine, as well as further interested to know further information contained therein. On a magazine cover consists of drawings and writings are arranged in such a way that looks interesting and has meaning Press publications, especially magazines, today's not enough just to rely on the quality of news or manuscript, although verbal aspect is very important. It must be recognized that the visual aspects (design) as the cover / envelope has crucial role to capture the prospective reader. For the cover of a magazine is a window that shows the content information, can be either a text or photographs, illustrations, and design elements. The function of a magazine cover is to attract, dazzle prospective readers, by way influence the thoughts flow in a short time. So it's no wonder much current the magazine publisher who made the cover of such a way as to attract the attention of prospective readers. Thus the task of designers to magazine cover to create designs that attract the attention of the reader becomes increasingly severe. This study tries to analyze a visual on the front cover Magazine Graphic Design 'Concept' birthday inaugural edition by using the Roland Barthes' semiotic approach. As Roland Barthes (1984), any simple "design work (magazine cover)" continue to play in management of the sign. So that will generate a message (image) specific. Design cover, usually contains the elements of the sign in the form of objects, context of the environment, people or other beings who provide meaning to objects, and text (of writing) that reinforce the meaning.Keyword: cover, magazine Concept, semiotics

Schwingungsüberlagertes Axialformen/Superimposed Oscillated Axial Forming

2020 ◽  
Vol 110 (11-12) ◽  
pp. 838-843
Author(s):  
Philipp Müller ◽  
Bernd-Arno Behrens ◽  
Sven Hübner ◽  
Hendrik Vogt ◽  
Daniel Rosenbusch ◽  
...  
Keyword(s):  
Surface Quality ◽  
Economic Importance ◽  
Combined Effect ◽  
Wird Eine ◽  
Forming Force ◽  
Forming Process ◽  
Forming Technology ◽  
Great Economic Importance ◽  
Gear Geometry

Techniken zur Steigerung der Formgebungsgrenzen in der Umformtechnik sind von hoher wirtschaftlicher Bedeutung. In dieser Arbeit wird eine Schwingungsüberlagerung im Krafthauptfluss eines Axialformprozesses zur Ausprägung einer Verzahnungsgeometrie untersucht. Die Auswirkungen der Schwingung auf die erzielbare Ausfüllung der Zahnkavitäten werden analysiert sowie die Parameter Schmierung und Oberflächengüte der Halbzeuge in ihrer kombinierten Wirkung untersucht. Es konnte eine Reduzierung der mittleren Umformkraft sowie eine Erhöhung der Formfüllung festgestellt werden. Techniques for extending the production limits in forming technology are of great economic importance. In this research, a superimposed oscillation in the main force flow of an axial forming process to form an axial gear geometry is investigated. The effects of the superimposed oscillation on the achievable form-filling of the tooth cavities are analyzed and the parameters lubrication and surface quality of the semi-finished products are investigated in their combined effect. A reduction of the averaged forming force as well as an increase of the form-filling could be achieved.

scholarly journals A quasi-monoenergetic short time duration compact proton source for probing high energy density states of matter

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
J. I. Apiñaniz ◽  
S. Malko ◽  
R. Fedosejevs ◽  
W. Cayzac ◽  
X. Vaisseau ◽  
...  
Keyword(s):  
Energy Density ◽  
Proton Beam ◽  
Dense Matter ◽  
High Energy ◽  
High Repetition Rate ◽  
High Energy Density ◽  
Time Duration ◽  
Ultrashort Pulse Laser ◽  
Proton Source ◽  
Short Time

AbstractWe report on the development of a highly directional, narrow energy band, short time duration proton beam operating at high repetition rate. The protons are generated with an ultrashort-pulse laser interacting with a solid target and converted to a pencil-like narrow-band beam using a compact magnet-based energy selector. We experimentally demonstrate the production of a proton beam with an energy of 500 keV and energy spread well below 10$$\% $$ % , and a pulse duration of 260 ps. The energy loss of this beam is measured in a 2 $$\upmu $$ μ m thick solid Mylar target and found to be in good agreement with the theoretical predictions. The short time duration of the proton pulse makes it particularly well suited for applications involving the probing of highly transient plasma states produced in laser-matter interaction experiments. This proton source is particularly relevant for measurements of the proton stopping power in high energy density plasmas and warm dense matter.

scholarly journals Effectiveness of Shock Wave Therapy as a Treatment for Spasticity: A Systematic Review

2020 ◽  
Vol 11 (1) ◽  
pp. 15
Author(s):  
Isabel María Martínez ◽  
Nuria Sempere-Rubio ◽  
Olga Navarro ◽  
Raquel Faubel
Keyword(s):  
Shock Wave ◽  
Botulinum Toxin ◽  
Methodological Quality ◽  
Scientific Evidence ◽  
Motor Impairment ◽  
Functional Independence ◽  
Shock Wave Therapy ◽  
Jadad Scale ◽  
Type Of Injury

Background: The purpose of this study was to collect and analyse the available scientific evidence on the effectiveness of shock wave therapy as a treatment for spasticity. Methods: the search was performed in the following databases: PubMed, PEDro, Cochrane, Embase, and the Virtual Health Library. All publications from November 2009 to November 2019 were selected that included a sample of patients with spasticity and prior suspension of botulinum toxin, to whom shock wave therapy was applied. The methodological quality of the articles was evaluated using the Jadad scale and the pyramid of quality of scientific evidence. Results: 25 studies involving 866 participants with spasticity were selected. The results obtained suggest that shock wave therapy appears to be effective in reducing spasticity levels irrespective of the age of the participants, the type of injury, and the tool used to measure the effect. Conclusions: shock wave therapy reports evidence of improvement in motor function, motor impairment, pain, and functional independence, applied independently of botulinum toxin. However, due to the heterogeneity of the protocols, there is no optimum protocol for its application, and it would be appropriate to gain more high-quality scientific evidence through primary studies.

scholarly journals High-Temperature Short-Time and Holder Pasteurization of Donor Milk: Impact on Milk Composition

Life ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 114
Author(s):  
Diana Escuder-Vieco ◽  
Juan M. Rodríguez ◽  
Irene Espinosa-Martos ◽  
Nieves Corzo ◽  
Antonia Montilla ◽  
...  
Keyword(s):  
High Temperature ◽  
Human Milk ◽  
Milk Composition ◽  
Donor Human Milk ◽  
High Temperature Short Time ◽  
Lactose Concentration ◽  
C 30 ◽  
Milk Banks ◽  
Short Time

Holder pasteurization (HoP; 62.5 °C, 30 min) is commonly used to ensure the microbiological safety of donor human milk (DHM) but diminishes its nutritional properties. A high-temperature short-time (HTST) system was designed as an alternative for human milk banks. The objective of this study was to evaluate the effect of this HTST system on different nutrients and the bile salt stimulated lipase (BSSL) activity of DHM. DHM was processed in the HTST system and by standard HoP. Macronutrients were measured with a mid-infrared analyzer. Lactose, glucose, myo-inositol, vitamins and lipids were assayed using chromatographic techniques. BSSL activity was determined using a kit. The duration of HTST treatment had a greater influence on the nutrient composition of DHM than did the tested temperature. The lactose concentration and the percentage of phospholipids and PUFAs were higher in HTST-treated than in raw DHM, while the fat concentration and the percentage of monoacylglycerides and SFAs were lower. Other nutrients did not change after HTST processing. The retained BSSL activity was higher after short HTST treatment than that following HoP. Overall, HTST treatment resulted in better preservation of the nutritional quality of DHM than HoP because relevant thermosensitive components (phospholipids, PUFAs, and BSSL) were less affected.

Effect of High-Energy Ball-Milling and TiB2 Content on Microstructures and Properties of Cu-TiB2 Composites Sintered by SPS

2006 ◽  
Vol 118 ◽  
pp. 661-665 ◽  
Author(s):  
Dae Hwan Kwon ◽  
Thuy Dang Nguyen ◽  
Pyuck Pa Choi ◽  
Ji Soon Kim ◽  
Young Soon Kwon
Keyword(s):  
Electrical Conductivity ◽  
Ball Milling ◽  
High Energy ◽  
High Energy Ball Milling ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Energy Ball ◽  
Xrd Patterns ◽  
Short Time ◽  
Tib2 Particles

The microstructure and properties of Cu-TiB2 composites produced by high-energy ball-milling of TiB2 powders and spark-plasma sintering (SPS) were investigated. TiB2 powders were mechanically milled at a rotation speed of 1000rpm for short time in Ar atmosphere, using a planetary ball mill. To produce Cu-xTiB2 composites( x = 2.5, 5, 7.5 and 10wt.% ), the raw and milled TiB2 powders were mixed with Cu powders by means of a turbular mixer, respectively. Sintering of mixed powders was carried out in a SPS facility under vacuum. High-energy ball-milling resulted in refinement of TiB2 particles. XRD patterns of milled TiB2 powders indicated broader TiB2 peaks with decreased intensities. After sintering at 950 for 5min using the raw and milled TiB2 mixture powders, the sintered density decreased with increasing TiB2 content regardless of milling of TiB2. In the case of raw TiB2, hardness rapidly increased from 4 to 44 HRB with increasing TiB2 content. The electrical conductivity changed from 95.5 to 80.7 %IACS. For mixtures of Cu powders with milled TiB2 powders, hardness increased from 38 to 67 HRB as TiB2 content increased, while the electrical conductivity varied from 88% to 51 % IACS. When compared to compacts sintered with raw and milled TiB2 powders, the electrical conductivity of specimens with raw TiB2 powder was higher than that of specimens with milled TiB2 powder, while hardness was slightly lower.

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