SMT Soldering Handbook surface mount technology 2nd phần 2 docx

... not fit into a wavesoldering or paste-printing routine (see Section 6 .2) . These robots apply a 22 Soldering job:LAY03 page :22 colour:1 black–text Table 3.7 Relationship between soldering parameters ... thickness Soldering method Confrontation Temperature Zone period °C °F thickness m Wavesoldering 2 5 sec 25 0 480 0.3–0.8 Reflow: Laser 0. 02 0.04 sec 25 0–350 480–900 O0.1 Vapo...

Ngày tải lên: 08/08/2014, 03:20

... 5 2 The SMD family 6 2. 1 Shapes, sizes and construction 6 2. 1.1 Melfs and chips 6 2. 1 .2 LCCCs 8 2. 1.3 SOs and PLCCs 9 2. 2 High-pincount components 9 2. 2.1 TABs 10 2. 2 .2 Flip-chips and BGAs 11 2. 3 ... black–text 3.1 .2 Soldering methods 21 3.1.3 Soldering success 24 3 .2 The solder 24 3 .2. 1 Constituents, melting behaviour and mechanical properties 24 3 .2....

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... conductivities in watt/cm °C Copper 3.9 Aluminium 2. 2 Brass 1 .2 Steel 0.5 Solder 0.5 Ceramic (alumina) 0 .25 FR4, rosin 0.0 02 Air 0.000 000 0 02 3.5 .2 Heating options Equilibrium and non-equilibrium ... itself (Figure 3.14). Wavesoldering, vapourphase soldering, hot air or gas convection soldering, impulse soldering and handsoldering with a soldering iron present equilibrium...

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... every surface it encounters. Both the ancient 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 ... may contain only small amounts of rosin, or none at all, flux vendors recommend higher underside temperatures, of up to 110 °C /23 0 °F with alcohol-based fluxes or 120 °C /25 0 °F for...

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... Pb melting point 139 °C /28 2 °F melting point 183 °C/361 °F melting point 22 1 °C/430 °F melting range 3 02 310 °C/576–590 °F Sequential soldering has been proposed in the past for reflowsoldering boards ... 3 .2. 4, item 3, for the beneficial effect of silver in solder): Solders to ISO 9453: I. 62. 5%–63.5% Sn II. 61.5%– 62. 5% Sn, 1.8% 2. 2% Ag* melting point 183 °C/361–361 °F melting poin...

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... energy K °C °F (watt/cm) 373 100 21 2 0.1 473 20 0 3 92 0.3 573 300 5 72 0.6 673 400 7 52 1 .2 773 500 9 32 2.0 873 600 11 12 3.4 973 700 129 2 5.1 1073 800 14 72 7.7 127 3 1000 18 32 15.0 emitted not only by ... a 20 2 Reflowsoldering job:LAY05 page: 62 colour:1 black–text Figure 5 .20 Principal features of an IR reflowsoldering oven temperature of the underside of the board at...

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... M. (1990) Development of a fluxless soldering process for surface mount technology. Soldering and Surface Mount Technology, No. 4, pp. 23 26 . See also USP 4.960 .23 6. 33. Nylen, M. and Norgren, S. ... production. Nepcon West, Anaheim, Cal., 26 Feb.–1 Mar. 24 . Reithinger, M. (1991) Reflow Soldering Technology for Surface Mount Assembly. Electr. Prodctn., March 1991, p...

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... polar 21 2 °F Methyl alcohol (methanol) 0.791 65.1 °C 12 C 20 0 polar 149 .2 °F54°F Ethyl alcohol (ethanol) 0.789 78.5 °C14°C 1000 polar 173.3 °F57°F Isopropyl alcohol (isopropanol) 0.786 82. 4 °C13°C ... after soldering 26 3 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 aspect of sol...

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... 1.0) (years) CFC 113 47.6 °C/117.7 °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 68 1.6 0. 02 0. 02 HCFC 141b 32. 0°C/89.6 °F 61 12 0.15 0.18 123 /141b- 30.0 °C/80.0 °F85— ... in Section 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...

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... 179, 24 2, 24 3 galvanic coatings, 23 9 gold-nickel, 23 9 hot-air levelling (HAL), 23 9, 24 0 organic solderability protection, 24 1, 24 2 rollertinning, 24 0, 24 1 solder depots for impulse soldering, 22 4, 22 5 solder-jet ... 14 Circuit-board: conveyors for reflowsoldering, 20 8, 21 4, 21 5 conveyors for wavesoldering, 126 – 128 robot-handling, 129 SMD-specific aspects, 23...

Ngày tải lên: 08/08/2014, 03:20