In ultrasonic tube hydroforming, the tube is hydro formed while the ultrasonic vibration is applied to the die. Prior studies provide experimental proof that ultrasonic tube hydroforming reduces corner radius, improves lubrication and uniform thickness. Use of ultrasonic vibration can decrease friction at the tube-die interface. Few attempts have been made to analyze the wire drawing while the ...

Deep drawing is a sheet metal forming process which is widely used in manufacturing parts for automobile and air craft industries. In this paper, the mechanism of deformation, effect of the geometrical parameters involved and the defects encountered in the process are presented and discussed. These include: the radial clearance percentage, punch and die profile radii. Despite the number of publ...

In this paper, hydroforming process of bent tubes in T-shaped die is studied for pulsating and linear pressure paths by the finite element method. Forming Limit Diagrams (FLDs) and thickness distribution curves are used to investigate the effect of pulsating pressure on hydroforming process. In addition, the obtained numerical results are compared with experimental results of hydroforming of st...

Deep drawing process is one of the widely used methods in sheet-metal forming. With the deep drawing method, products of various geometrical shapes such as saucepans, tubes, perfume and soft drink cans can be obtained easily. Therefore, the optimization of the deep drawing process is very important for the industry. In conventional deep drawing method, no angle is given to the surfaces of die a...

Die elektrostatische Wechselwirkung dominiert die Adsorption von Polyelektrolyten an Oberflächen, die Bildung von Komplexen und die Bindung von Liganden an Makromoleküle. Die effektive Ladung von Polyelektrolyten wird durch die nominelle Ladungsdichte und die Gegenionenkondensation, die vom umgebenden Medium abhängt, bestimmt. Elektrophorese-NMR zusammen mit DiffusionsNMR erlaubt es, die effekt...

The Effects of Downstream Distributor Chains on Upstream Producer Entry: A Bargaining Perspective by Suchan Chae and Paul Heidhues This paper studies the effects of integration among downstream local distributors on the entry of upstream producers in a bargaining theoretic framework. We show that integration of downstream distributors may increase their bargaining power vis-à-vis upstream produ...

In diesem Artikel wird die Entwicklung eines Informationssystems auf Basis von Open-Source-Komponenten vorgestellt, das die Darstellung des exakten Standortes eines Webseitenbetreibers einer aufgerufenen Webseite automatisiert. Aktuelle, im Web gängige Systeme gestatten die genaue Darstellung eines Ortes erst nach Eingabe der zugehörigen Adresse oder verwenden zur Bestimmung von Standortdaten G...

A series of semicrystalline triblock copolymers E/EP/E, of poly(ethy1ene) (E) and poly(ethylenepropylene) (EP) were subjected to high levels of plane strain compression using a channel die. The processing was carried out at 150 "C, a temperature which lies well above both the E block melting points (99-103 "C) and the quiescent order-disorder transitions (ca. 106 "C) for these samples. The lame...

A numerical trajectory optimization study of two types of lifting-entry reentry vehicle has been presented at low suborbital speed of 4.113 km/s and -15 degree entry angle. These orbital speeds are typical of medium range ballistic missile with ballistic range of approximately 2000 km at optimum burnout angle of approximately 41 degree for maximum ballistic range. A lifting reentry greatly enha...

Schwebstoffteilchen erfahren in einem diffundierenden Gasgemisch eine Kraft, die sie im allgemeinen in Richtung des Diffusionsstromes der schweren Moleküle bewegt. Die daraus resultierende Geschwindigkeit wurde an Teilchen von verschiedenem Radius in einem Netz-Schwebekondensator und in verschiedenen binären Gasgemischen gemessen in Abhängigkeit vom Druck und vom Mischungsverhältnis. Das Verhal...