We describe the replication of a relief grating that behaves like a polarizing beam splitter by injection molding. Measurements of the grating master, nickel shim, and replica, performed by atomic force microscopy, allow establishing a limit for the injection molding technique (currently used in CD fabrication) to aspect ratios of approximately 0.15. Although this limit strongly reduces the dif...

The design of injection molding systems for plastic parts relies heavily on experience and intuition. Recently, mold makers have been compelled to shorten lead times, reduce costs and improve process performance due to global competition. This paper presents a framework, based on a Multidisciplinary Design Optimization (MDO) methodology, which tackles the design of an injection mold by integrat...

PVT (Pressure-Volume-Temperature) properties of polymers are important for both engineering and polymer physics. Fig.1 shows the typical PVT diagrams of an amorphous (a) and semi-crystalline polymer (b). PVT diagram describes the specific volume as a function of pressure and temperature. Specific volume increases with the temperature increasing. There is a thermal transition in the polymer. The...

A stiffness-based ejection condition for injection molding is introduced and utilized for evaluation of different polymer materials. Comparison with industrial practice and other commonly used ejection criteria, such as molded part temperature, indicates that this approach not only can be an alternative when the ejection temperature of the polymer part is unavailable, but also is able to better...

This work follows the general framework of polymer injection moulding simulation whose objectives are the mastering of the injection moulding process. The models of numerical simulation make it possible to predict the propagation of the molten polymer during the filling phase from the positioning of one point of injection or more. The objective of this paper is to propose a particular way to op...

Tools for injection molding are very expensive parts of this kind of production and they must be handled very carefully. An important part of their handling is the management of data related to the tools. The important data for injection molding tools is possible divide to different areas economical, technological, production etc. With an increasing impact of information technologies on manufac...

We numerically investigate the stability problem of the injection molding process. It was indicated by Bulters and Schepens Bulters and Schepens 2000 that surface defects of injection molded products may be attributed to a flow instability near the free surface during the filling stage of the mold. We examine the stability of this flow using the extended Pom–Pom constitutive equations. The mode...