Plastic laser

LEW is a versatile process and can be used to weld a variety of materials including carbon steels, stainless steel, titanium, aluminium, nickel alloys and plastics. Lasers are often used in high-volume production applications as they have high welding speeds and a level of automation which allows them to be used in numerically controlled machines and robots. They are also used to weld dissimilar metal combinations. 

Diaz-Garcia, M.A., et al. 1997. Plastic lasers. Appl Phys Lett 70 3191. 

Interest in the phenomenon of laser action in -ir-conjugated polymers continues to grow. This is largely due to the possible applications of these polymers as active laser media in future plastic laser diodes. Hence, better understanding of the various mechanisms leading to SN and the criteria... 

Proposed more than 10 years ago, a new concept is attracting a lot of interest, the plastic LEDs and plastic lasers [50], which are based on neutral, not conductive conjugated polymers, where conductive polymers are intended to be used as the hole injection layer. But this area has by far not yet reached a market acceptance as has been hoped for or predicted by the active scientists, companies, and the interested public. 

ELNakamura, Application to the Automotive Parts of Plastics Laser Welding JSFT 05 Tech. Papas 119-122... 

P. Rooney, Plastic Laser Welding, ANTEC, 808 (2002) M. Chen, G. Zak, P.J. Bates, Laser Absorption Coefficient Measurement of Amorphous Polymers for Laser transmission Welding, ANTEC, 2291 (2006)... 

Key Words Engineering plastics, laser-welding, transparency, scattering. 

Europium oxide is now widely used as a phospor activator and europium-activated yttrium vanadate is in commercial use as the red phosphor in color TV tubes. Europium-doped plastic has been used as a laser material. With the development of ion-exchange techniques and special processes, the cost of the metal has been greatly reduced in recent years. 

Applications. The applications sought for these polymers include composites, stmctural plastics, electronics/circuit boards, aircraft/spacecraft coatings, seals, dental and medical prosthetics, and laser window adhesives. However, other than the early commercialization by Du Pont of the NR-150 B material, Httie development has occurred. These polymers are quite expensive ( 110 to 2200 per kg for monomers alone). 

In electrical porcelains (often called steatite bodies), high purity talc products with low levels of alkali metals ate preferred. A typical steatite is made from 85% talc, 10% plastic kaolin, and 5% BaCO. Steatites ate used as insulators on high voltage equipment such as automotive starters, microwave oven generators, and laser generators. 

A typical shock-compression wave-profile measurement consists of particle velocity as a function of time at some material point within or on the surface of the sample. These measurements are commonly made by means of laser interferometry as discussed in Chapter 3 of this book. A typical wave profile as a function of position in the sample is shown in Fig. 7.2. Each portion of the wave profile contains information about the microstructure in the form of the product of and v. The decaying elastic wave has been an important source of indirect information on micromechanics of shock-induced plastic deformation. Taylor [9] used measurements of the decaying elastic precursor to determine parameters for polycrystalline Armco iron. He showed that the rate of decay of the elastic precursor in Fig. 7.2 is given by (Appendix)... 

M. Bcrggren, A. Dodabalapur, R. E. Slusher, Organic solid-state lasers with imprinted gratings on plastic substrates, Appl. Phys. Leu. 1998, 72, 410. 

Methods are used to produce the more costly rapid prototypes include those that produce models within a few hours. They include photopolymerization, laser tooling, and their modifications. The laser sintering process uses powdered TP rather than chemically reactive liquid photopolymer used in stereolithography. Models are usually made from certain types of plastics. Also used in the different processes are metals (steel, hard alloys, copper-based alloys, and powdered metals). With powder metal molds, they can be used as inserts in a mold ready to produce prototype products. These systems enable having precise control over the process and constructing products with complex geometries. 

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