Fluxes clean

The secret to a good bond, especially when working with solar cells, is using the right flux and using it correctly. Flux cleans the metal surface and reduces surface tension between the solder and the metal it will adhere to. This is important to make a good electrical contact. Do not bother with paste or liquid flux. Use the flux pens indicated in the materials section. The pen will put the right amount of flux down and do it... 

Is Your Solder Pad Joining "Hairy" As part of a solder/flux/ cleaning procedure, the residue In Figure 10 (Insert) was produced. The residue consists of 6xl0pm leaf-like crystals on a ceramic substrate. The location of the residue prevented Its analysis In-sltu, so extraction replication(5) was used to remove some of the crystals for analysis by several small area techniques, as needed. Electron probe microanalysis showed lead, carbon and oxygen, which could Indicate many possibilities. 

Co-solvent-4 Minute Boil Sump, 2 Minute Rinse RMA No Sump Flux Clean Flux... 

Table I. Rosin Flux Cleaning Power of Selected VMS Azeotropes...

RMA RMA No Flux No Clean Flux Clean Flux Flux... 

Soldering flux is applied prior to component placement and soldering. Flux choice should be tailored to the hot-bar process.The flux can be either liquid or paste. TTie flux chosen should be tested to resist charring and the development of polymerized decomposition products, or lacquers, which adhere to both circuit board and hot-bar. Residue build-up on the bar can adversely inhibit hot-bar performance by diminishing thermal transfer. The residue can also become thick and uneven enough to prevent the hot-bar from squarely contacting component leads. Baked-on aqueous-clean flux residues can make flux cleaning difficult. With no-clean flux, overheated residues may detract from the visual appearance of the printed circuit assembly. 

Fluxes remove oxides hy dissolving or undercutting them and floating the surface layers away. Fluxes are commoidy used in welding and soldering hut not commonly used in cleaning for film deposition. However, gallium and indium have been used to flux clean silicon surfaces in vacuums. 

Fluxing (cleaning) A metal-cleaning technique that operates by dissolving or floating off the oxides on a surface using a hot molten fluid solvent, which is often a borate. 

FIGURE 18.10 Variation of the normalized fluxes (Grand River water flux/clean water flnx) between base PVDF and modified PVA/PVDF membranes (a) at the beginning of UF (a) and (b) at the end of UF. Dnration of UF cycle is 2 h, followed by the membranes cleaning with NaOH solution. (Data from J.R. Du et al., Water Res, 43, 4559-4568, 2009.)... 

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