SMT Soldering Handbook surface mount technology 2nd phần 7 pot

... Proc. Electronic Comps. and Technology Conf., pp. 5 07 510. 37. Lea, C. (1989) Lasersoldering – Production and Microstructural Benefits for SMT. Soldering and Surface Mounting Technology, No. 2, pp. ... 26 Feb.–1 Mar. 24. Reithinger, M. (1991) Reflow Soldering Technology for Surface Mount Assembly. Electr. Prodctn., March 1991, pp. 27 37. 232 Reflowsoldering job:LAY06 page:9 co...

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... heated surface. Copper may have a higher heat capacity and thermal conductivity than solder (Table 4.1), but molten solder adapts to the shape of every surface it encounters. Both the ancient soldering ... soldering iron and some of the latest techniques of desoldering and resoldering SMDs make use of this conveni- ent fact, by always working with a soldering bit well covered with mo...

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... Thus, for a board surface populated entirely with SMDs, reflowsoldering is the natural choice. A leading vendor of both wave- and reflowsoldering equipment stated recently (19 97) that 80% of all ... threat to wavesoldering and its associated technologies of placing and curing SMD adhesives. Overhead soldering Reflowsoldering boards with SMDs on both sides involves ‘overhead soldering , for...

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... 326 9.2 Soldering success and soldering perfection 3 27 9.2.1 Soldering success and soldering faults 3 27 9.2.2 Soldering perfection and soldering imperfections 330 9.3 Practical examples of soldering ... not arise with soldering methods where only the leads are The SMD family 17 job:LAY00 page:3 colour:1 black–text SMT Soldering Handbook Rudolf Strauss, Dr.Ing., FIM...

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... sphere: in effect, the surface behaves like a tensioned skin which encloses the molten solder, hence the term surface tension’ (Figure 3.11). Surface tension, tending to reduce the surface of a given ... are not only its own surface tension, but also the so-called ‘interfacial tension’ or wetting force, which pulls the solder across the surface of the substrate. Soldering 47 job:...

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... itself (Figure 3.14). Wavesoldering, vapourphase soldering, hot air or gas convection soldering, impulse soldering and handsoldering with a soldering iron present equilibrium Soldering 61 job:LAY03 ... total, as Figure 3. 27 shows. 3 .7 References 1. Strauss, R. (1992) The Difference between Soldering Success and Soldering Quality; its Significance for Quality Control and Correct...

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... thermal energy K °C °F (watt/cm) 373 100 212 0.1 473 200 392 0.3 573 300 572 0.6 673 400 75 2 1.2 77 3 500 932 2.0 873 600 1112 3.4 973 70 0 1292 5.1 1 073 800 1 472 7. 7 1 273 1000 1832 15.0 emitted not ... reflowsoldering oper- ation. *After Reithinger, M. (1991) Reflow Soldering Technology for Surface Mount Assembly, Electr. Productn., March 1991, pp. 27 37 The starting p...

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... °F Methyl alcohol (methanol) 0 .79 1 65.1 °C12°C 200 polar 149.2 °F54°F Ethyl alcohol (ethanol) 0 .78 9 78 .5 °C14°C 1000 polar 173 .3 °F 57 F Isopropyl alcohol (isopropanol) 0 .78 6 82.4 °C13°C 400 polar 180.3 ... after soldering 263 job:LAY08 page: 17 colour:1 black–text Cleaning after soldering or ‘defluxing’, in spite of the growing use of no-clean fluxes, is still an important aspec...

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... 3.3.5. See also References 22 and 23 of Chapter 3. 9.2 Soldering success and soldering perfection 9.2.1 Soldering success and soldering faults In soldering, two things matter before all others, as ... Boiling point K  Atmospheric ODP GWP value life (CFC 11 = 1.0) (years) CFC 113 47. 6 °C/1 17. 7 °F 27 90 0.85 1.3 CHC 111 74 .1 °C/165.4 °F 124 6.3 0.13 0.02 HCFC 123 28.0 °C/82.4 °F...

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... 53 Cleaning: by high-pressure jets, 273 , 289, 303, 309 by ultrasonics, 272 , 273 by vapour jet, 291 chemistry of, 274 , 274 contaminants to be removed, 2 67 269 hydrodynamic apects, 269– 273 Cleaning efficiency: effect ... measurement methods, 74 78 Solderability testing, 79 , 80 Solderable component leads, 10, 14–16, 41, 43 Solderable surfaces on circuitboards, 238–243 flat solder depots...

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