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1-) Elastic Modulus ( New ) - ( Better ) - ( Material Property )
We shall discuss the deformation of solids in terms of the concepts of stress and strain. Stress is a quality that is proportional to the force causing a deformation; more specifically, stress is the external force acting on an object per unit cross-sectional area. The result of a stress is strain, which is a measure of the degree of deformation. It is found that, for sufficiently small stresses, stress is proportional to strain; the constant of proportionality depends on the material being deformed and on the nature of the deformation. We call this proportionality constant the elastic modulus. The elastic modulus is therefore defined as the ratio of the stress to the resulting strain:

               Elastic modulus = stress / strain

The elastic modulus is general relates what is done to a solid object ( a force is applied) to how that object responds ( it deforms to some extent ). It is similar to the spring constant k in Hooke' s Law that relates a force applied to a spring and resultant deformation of the spring, measured by its extension or compression.
We consider three types of deformation and define an elastic modulus for each:

1-Young's modulus measures the resistance of a solid to a change in its length.
2-Shear modulus measures the resistance to motion of the planes within a solid parallel to each other.
3-Bulk modulus measures the resistance of solids or liquids to changes in their volume.

( Jewett, Serway, Physics for Scientists and Engineers, Volume 1, pg. 358 )

OLD ONE:

Elastic modulus:The modulus of elasticity, or Young's modulus (E) is the slope of the stress-strain curve in the elastic region. The relationship is Hooke's Law:
E = σ/ε

The modulus is closely related to the binding energies. A steep slope in the force-distance graph at the equilibrium spacing indicates that high forces required to separate the atoms and cause the material to stretch elastically. Thus, the material has a high modulus of elasticity. Binding forces, and thus the modulus of elasticity, are typically higher for melting point materials. In metallic materials, modulus of elasticity is considered a microstructure insensitive property since the value is dominated strongly by the strength of atmoic bonds. Grain size or other microstructural features do not have a very large effect on the Young's modulus. Note that Young's modulus does not depend on such factors as orientation of a single crystal material. For ceramics, the Young's modulus depends on the level of porosity. Young's modulus of a composite depends upon the stiffness and amounts of the individual components.

Young's modulus is a measure of the stiffness of a component. A sitff component, with a high modulus of elasticity, will show much smaller changes in dimensions if the applied stress is relatively small and, therefore, causes only elastic deformation.

(The science and engineering of materials, Donald R. Askeland, Pradeep Prabhakar Phulé, 5th Edition, p. 198)

2-) Metal Injection Molding ( New ) - ( Better ) - ( Manufacturing Method )
Metal injection molding ( MIM ) is the process of mixing elemental or alloyed powders with thermoplastic binders. The binders are selected to deliver the optimum flow characteristics to facilitate uniform distribution of the material in the mold.
Under moderate pressures and temperatures, the material is extruded into a mold. The material hardens as it cools and is removed from the mold in what is called the " green " condition. At this point, the part is larger than the desired shape by the amount of binders used in the mixture. These binders are preferentially and selectively extracted from the " green " part. Generally, a low-temperature furnace treatment slowly evaporatess the binder over a 1 - 3 day period. The parts are then sintered in a high-temperature furnaceunder controlled atmospheric conditions, and a temperature profile is selected to remove the remaining binders and present a finished part with the desired physical properties. Obviously, the entire process lends itself admirably to microprocessor control.

( Brown, James, Modern Manufacturing Processes, pg. 1 )

OLD ONE:

Metal Injection Molding

Injection molding is closely associated with the plastic industry. The same basic processses can be applied to form parts of metal or ceramic powders, the difference being that the starting polymer contains high content of particulate matter, typically from %50 to %85 volume. When used in powder metallurgy, the term metal injection molding (MIM) is used. The more general process powder injection molding (PIM), which includes both metal and ceramic powders. The steps in MIM proceed as follows:

1. Metallic powders are mixed with an appropriate binder.

2. Granular pellets are formed from the mixture.

3. The pellets are heated to molding temperature, injected into a mold cavity, and the part is cooled and removed from the mold.

4. The part is processed to remove the binder using any of several thermal or solvent techniques.

5. The part is sintered.

6. Secondary operations are performed as appropriate.

(Groover M. P., Fundamentals of Modern Manufacturing: Materials, Processes and Systems 3rd Edition, p. 352)

3-) Rubber Injection Molding ( New ) - ( Better ) - ( Manufacturing Method )
Many rubber articles are produced by molding, a process in which uncured rubber, sometimes with an insert of textile, plastic, or metal, is cured under pressure in a mold. There are three general molding techniques: compression, transfer and injection molding.
Injection molding combines an extruder, which heats and fluxes the rubber, with a reservoir and mold. While the rubber in the mold is curing, fresh rubber is prepared for the next cycle so that molding is a semi-continuous process. The compounds used have to be optimized for injection molding. They must flow through the nozzle and runner system and fill the mold under the pressure available. They should not cure before filling the mold, but cure quickly once in the mold.
A high viscosity compound may not fill the mold properly or may generate too much shear heat, leading to overheating and scorch. A low viscosity compound may not generate enough heat, leading to undercure. These considerations mean that there is a process window within which a specific material can be satisfactorily molded in a given process.
Both compression molding and transfer molding have been used in the rubber industry for many years, whereas injection molding did not become common in the rubber industry until after it had been developed as a standart process in the thermoplastics industry in the 1960s.

( Johnson, Peter S. Rubber Processing An Introduction, pg. 119 )

OLD ONE:
Rubber injection molding: The inherent complexity of various rubber compounds and their peculiar flow behaviour during molding reqires speacial attention.An integral approach to injection molding of rubber is needed which will take into account allmajor aspects of rubber behaviour, including modeling of flow into extruder, nozzle, sprue, runner system,and cavity, curing behaviour, packing, mold design, rheology and effect of processing upon structure and properties of molded products. A description of this integrated concept is the major trust of rubber injection molding.The process of rapidly forcing an exact amount of rubber from a tube/cylinder into a closed, heated mold. This process provides economical advantages including short molding cycle ,lower unit cost, high dimensional tolerances, absence of flash and little scrap/waste.

(Injection and Compression Molding Fundamentals Isayev, A IMarcel Dekker, Inc , 270 Madison Ave , New York, New York 10016, USA, 1987. 703 pp., p.436)

4-) Jet Plating ( New ) - ( Better ) - ( Methods used to increase rate of deposition )

All the methods listed below have been utilized on experimental, pilot or commercial scale.

Cathode movement - rotation or oscillation
Air agitation
Paddles and impellers
Viratory agitation
Jet planting
Turbulent flow
Ultrasonic agitation
High-frequency current pulsing
Laser-enhanced plating
Brush plating
Abrasive plating
Fluidized-bed techniques

Jet Plating
Jet plating is a high-speed electroplating technique. Due to its special flow characteristics it can be used to localize theelectrodeposition reaction on an unmasked cathode.The most outstanding application of jet plating is in the electronics industry for the selected-area plating of lead frames on reel-to-reel plating machines. The most important metals are gold and silver but nickel plated from sulphamate baths is often used as an undercoat. Fast rate plating is achieved by impinging a jet of solution onto a localized area defined by a gasketed ( mask ) template. Multi-layer coatings can be deposited sequentially using this technique. Thin coatings with good distribution can be achieved in a very economical manner.

( Dennis, J.K. Such, T.E. Nickel and Chromium Plating, pg. 427-429 )
( Karakus, C. Chin D. T. Journal of the Electrochemical Society, Abstract )

OLD ONE:

Jet Plating:

The most outstanding application of jet plating is in the electronics industry for the selected-area plating of lead frames on reel to reel plating machines. The most important metals are gold and silver but nickel plated from sulphamete baths is often used as an undercoat. Fast rate plating is achieved by impinging a jet of solution onto a localized area defined by a gasketed (mask) template. Multi-layer coatings can be deposited sequentially using this technique. Thin coatings with good distribution can be achieved in a very economical manner.

Raub has developed a cell for simulating high-speed electrodeposition by jet plating. Results are published for the deposition of chromium and palladium/nickel alloys as well as for other metals. In the case of chromium the mixing of the electrolyte is not solely due to hydrodynamic flow but also to stirring by gas bubbles. Comparative information is given for palladium/nickel alloys deposited by jet plating and rotating cathode techniques. Bocking has reported the results of high speed selective jet electrodeposition. The purpose of this research is to achieve direct writing of electrical and electronic devices. Simon has also described laboratory experiments which made use of high velocity jets of electrolytes for deposition of hard gold coatings at current densities ip to 50 A/dm^2.

(Nickel and chromium plating, J. K. Dennis,T. E. Such, p.429)

5-) Liquid-Crytal Polymers ( New ) - ( Material )
The liquid crystal and the polymer are two different disciplines of science and technology. They meet together producing the liquid crystalline polymer or, is you prefer, the polymeric liquid crystal. The liquid crystalline polymer combines mesogenic units and high molecular weight, and thus exhibits excellent anisotropic physical properties while processing the advantage of easy processing and convenient molecular tailoring. The liquid crystalline polymer not only possesses the individual properties of each of its parents, but also exhibits intrinsic features that its parents do not have. In such a sense, the liquid crystalline polymer is a new state of matter.
Both the liquid crystal and the polymer are of about the same age, but the polymer has successfully penetrated every walk of human life. On the other hand, the liquid crystal had kept itself quite for a half century until the early 70's. Since then, it has caught the vast interest of both science and industry. It has been applied especially in the display industry, such as in portable TVs and notebook and desktop computers. Two important events symbolized the liquid crystal's coming of age: Professor P. G. de Gennes, a French physicist, won the Noble Prize in 1991 and Professor G. W. Gray, a British chemist, was awarded the Kyoto Prize in 1995.
Liquid crystalline polymers are a kind of polymer that show liquid crystal phases. They are composed of low molecular mass liquid crystals, which can be either rod-like or disc-like, or rod- and disc-like together in one. The constituent blocks may be of very complicated two-dimentional or three dimentional shape. They may be composed of amphiphilic molecules as well.

( Johnson, Peter S. Rubber Processing An Introduction, pg. Preface, 10 )

THERE IS NOT OLD DEFINITION !!!