In a lot of industry application, thermoplastic the treatment means that the laser of component solders to had made a standard. When use diode laser, Nd:YWhen AG laser or fiber-optic laser, standard operation is to be in coincide place to undertake projecting type laser beam welding is received. Focusing laser radiate is penetrable superstratum is transparent plastic, be absorbed by lower level material, absorption radiant energy is changed into heat energy in the surface, as a result of the conduction of heat energy, form contact in superstratum. Unbleached or of coloured plastic the absorption in close infra-red wave band is inferior. Carbon black is additive of a kind of colophony, it can be in very wide wave band (from arrive it is thus clear that infra-red) rise effectively plastic the absorptivity to laser. However, if used carbon black, plastic can make it is brunet, cannot the plastic component with transparent make it. Solder by British Cambridge institute (TWI) the Clearweld craft of development makes transparent or coloured is plastic can absorb close infra-red light effectively. It was used special close infra-red the coating that absorbs material to regard component as the surface, in perhaps serving as additive mix into to enter lower colophony. These material are in the absorption inside visible light limits is lesser, in close red outskirt (800-1100 Nm) absorb bigger. Current, in the biggest absorption near wavelengh, those who have all sorts of differring is narrow the absorption that absorbs bandwidth material, they can be used to adjust plastic optical character, so that get used to all sorts of common close infra-red laser. Besides depend on uses laser wavelengh, first-rate absorbs material to still depend on the requirement on specific application, machine the color that character of parameter, material and object element place need for instance. Graph 1, the transmission curve of transparent PMMA base material, and after PMMA surface applied Clearweld coat, the transmission curve in laser radiate around (Zun Tu) . The result of earning is clean and transparent solder contact, plastic without the change primary colors (right graph) . Clearweld coating craft is contained absorb limits to be in the coating of 940-1100 Nm absorbefacient low the agglutinant, wet goods that is based on solvent, be applied in all sorts of burden systems. Typical dissolvent is alcohol and acetone. The dosage of coating rises with accept / square millimeter (NL/mm2) for the unit. Solvent can serve as carrier, volatilize very quickly, form to recruit material film in plastic surface thereby. Normally, dry time is in 1 to 7 seconds. Also can use auxiliary and dry method, use infrared light for example to the spare parts heat beforehand or hind heat, of your dissolvent volatilize more rapid. Coating process is OK with solder the process undertakes apart. Arrive when coating application when material surface, an even absorbefacient layer is in with respect to deposit the surface of material. It is before laser radiate, dry the coating after has trifling color in visible wave band. When undertaking soldering, stimulate ray radiation to be absorbed by coating, be changed into heat energy at the same time. Because heat is conducted, face the surface that is bordering on coating to material is heated and fuse, solidify hind formed solder place. In heating process, absorbefacient is decomposed, the color that coating lost visible wave band completely (see a picture 1) . Graph 2, the match colors that passes a success, pervious to light superstratum and absorbefacient lower level may look exactly like, the process soldered to also get optimizing in the meantime. Additive absorbefacient is returned but by at a lot of thermoplastic in material, it is joined as additive lower is plastic in receive a process in order to assist laser beam welding. This process is similar to carbon black is added in material, nevertheless, the color here is more diversiform, can be used at transparent / in opaque plastic spare parts. The basis applies the diverse demand that go up, technical personnel can use Clearweld absorbefacient craft to adjust the deepness with fused material. The chroma that passes the absorbefacient in changing colophony will realize this. Absorbefacient chroma and optical penetration are direct and relevant, raise chroma to make penetration is reduced, also reduced fused deepness thereby. If need a very big bath to correct aperture and geometrical error, and do not hope get together more content is plastic by hot degradation, so the chroma of absorbefacient can be set a few lowlier. If what need the dimension of bath is lesser, for instance, in the application of miniature fluid equipment, so the chroma of absorbefacient is OK a few taller. In the specific mixture colophony that contains Clearweld additive is designed and soldering with the laser at 800-1100 Nm wave band. These colophony are in order to note a pattern or the form of extrusion die is made, in mixture process, their color can undertake match colors through colorant, will in order to obtain a specific recipe realize specific applied requirement. This recipe needs to consider the parameter of a lot of respects, include to get together more requirement of the compatibility of content, color, and solder the wavelengh of laser. Graph the 2 transparent and plastic sample that are the yellow that laser beam welding receives and orange. Through undertaking match colors successfully, pervious to light superstratum and absorbefacient lower level may look exactly like, the process soldered to also get optimizing in the meantime. But, sometimes the laser wavelengh that the requirement of color may decide to need and other parameter. The colophony that can solder and these additive can make mixture squashing model is noted inside model, model together, perhaps squash filmy, after be being rushed to cut, this film can be used at laser beam welding to receive medium among transfer layer. Solder oil storage implement graph the 3 oil storage that receive for laser beam welding implement, it is by transparent achromatic PMMA plastic make. This spare parts is those who be in company of Barkston plastic industry is semi-automatic change what make on product line. Solder in use laser previously, this product rises through adhesive join, among them each component is to carry sophisticated machine cut, additional amend the treatment process such as the polish with the surface to come true. Solder through 940nm diode laser and coping and bottom flat cap and the post among are become. Soldering previously, clearweld coating is added in the brim of post. Dry hind, component is assembled, clamp apposition receives a stage to go up at laser beam welding. Solder the process is to pass the solder wiring road of a circle to come true, the laser light beam of focusing crosses cap to shoot the brim of post from coping. In whole process, the coating in post upside brim by degradation, make another brim of bottom cap place, post also is soldered at the same time. Because laser is reflexed in post parietal interior,this is, so laser light beam is brought to across. Laser beam welding receives gotten fluid solder contact very close together, intensity is very high, and have very good optical appearance. Use Clearweld coating, coping and bottom can be soldered to go up to post by laser at the same time. This makes manufacturing time remarkable reduce, product quality rises apparently, because the product has vacuum sealed character, and whole product is completely transparent. Oil storage implement production can achieve economy model, small lot production, every approve 50 products. Solder medical pipe fitting is in in cooperating with Natvar company, we use additive to draw laser energy, solder the pipe that needs in medical treatment application (if pursue 4) . Normally, these products are to use ultraviolet light to stick receive or the means of solvent joint will come true. Ultraviolet light sticks the solidify time that receives a second of constant need 15-20. Solvent joint is instant, but must want to join a kind of chemical to generate contact. Ultraviolet light is stuck receive the means with solvent joint to need to contact port surface in whole process (taper shrinks gradually place) , normal lengths can be amounted to 0. 250-0.
500 inches. These pipe can be mixed through pipe lining outer the requirement that mixture extrusion will come to realize bushing, of pipe exterior it is surface of softness, touchable. This surface layer can be those who differ is plastic thermoplastic perhaps man-made balata material, for instance PVC, TPU, TPE, or COPE. What additive is added in pipe wall is outer, can use laser to solder so pipe the port part of two end. Pipe and port place must be transparent achromatic, so that measure,shed the liquid of classics pipe. Combine a course through pressing, port is secured on pipe. Use plastic of beam of light, laser beam welding receives a process to be able to form annular contact, undertake synchronously soldering thereby. Pressure add up to a process not to need additional clamping apparatus to secure. Such, laser soldered to form sealed contact in the upright ministry of pipe, should solder to do not have any influences to the diaphaneity of component. Stick with ultraviolet light receive and photograph of solvent joint method is compared, the main dominant position that laser beam welding accepts is it can form a mechanical link, do not need other any solvent or cement. Compare with traditional methodological photograph, want to form a mechanical link, laser beam welding accepts need 0.
125 inches length. The standard of this length and commonly used craft can is likened to, want the commonly used technology with current excel even. Additional, laser beam welding receives place to need time to be less than 0.
5 seconds, and ultraviolet light is stuck receive a time of solidify of need 15-20 second. In a few application, the interface that needs to have different kind in the two end of pipe (use solvent joint one end, stick by ultraviolet light receive another end) . And laser beam welding is received applicable to two end, and solvent joint craft cannot come true. Transparent thermoplastic get together more content is plastic also can undertake with man-made balata laser solders, can use close infra-red absorb material to produce region of heat energy standoff to fuse. This technology applies already successfully at different situation, make clear Clearweld coating or additive can match thermoplastic the absorption of material is characteristic, make these material can realize laser beam welding to receive on industry thereby. Laser welder skill gets transparent achromatic welding line quite. Laser energy hands over the welding line place of the face to be absorbed in two component only. Other area does not absorb any radiation, there is additional thermal stress on such workpiece. Use additive, technical personnel can get the contact of high quality. Compare with use coating photograph, according to the different chroma of absorbefacient, laser radiant energy is in quite data is inside more in be absorbed. Formed the melt material with larger volume so, its larger to compensation crack, or for the error with bigger cram more advantageous. Additive very agree with coloured is transparent / of opaque base material note a pattern, these base material are applied at container of equipment of the crust of electronic product, medical treatment, liquid, with the component with lesser etc, or other contains older weld zone the component of region. Solder through very good adjustment parameter, can make the exterior of welding line neat, and solder intensity is high. Laser beam welding received a technology to offer contact of clean and neat optical and colorless solder, vacuum for engineers sealed character, agile design, produce without contact, without particle and the treatment process that has glitter hardly, and this technology does not need adscititious material serve as adhesive. This technology is in medical treatment, electron, car, textile, pack and consumable market came true new-style and advanced plastic laser solders. In addition, uses additive and coating have biology consistence. Article author R.
Klein (rklein@gentexcorp.
Com) comes from branch of Gentex company Germany (Gross-Umstadt) . G.
McGrath comes from branch of England of Gentex Corporation company (Cambridge) . Firm network address: Www.
Gentexcorp.
Com. The Tony Blackmore of company of plastic engineering of the Bob Donohue of company of Natvar of two authors acknowledgment and Barkston, and the assistance of the group of research of Gentex company Clearweld that is located in American Carbondale. CNC Milling
CNC Machining