Solder is a fusible metal alloy used to join together metal workpieces and having a melting point below that of the workpiece(s).
electrical and electronics work solder wire is available in a range of thicknesses for hand-soldering, and with cores containing flux. It is also available as a paste or as a preformed foil shaped to match the workpiece, more suitable for mechanized mass-production. Alloys of lead and tin were universally used in the past, and are still available; they are particularly convenient for hand-soldering. Lead-free solder, somewhat less convenient for hand-soldering, is often used to avoid the environmental effect of lead.
Lead Solder Wire
Tin/lead solders, also called soft solders, are commercially available with tin concentrations between 5% and 70% by weight. The greater the tin concentration, the greater the solder’s tensile and shear strengths. Alloys commonly used for electrical soldering are 60/40 Tin/lead (Sn/Pb) which melts at 188 °C and 63/37 Sn/Pb used principally in electrical/electronic work.
The 63/37 is a eutectic alloy, which has the lowest melting point (183 °C or 361.4 °F) of all the tin/lead alloys and the melting point is truly a point — not a range.
Currently we stock due to its strength and melting point properties.
63/37 Tin-lead alloy solder,0.5mm,250g
63/37 Tin-lead alloy solder,1.63mm,250g
Lead-Free Solder Wire
On July 1, 2006 the WEEE and RoHS directives came into effect prohibiting the intentional addition of lead to most consumer electronics produced in the EU.
Therefore all consumer electronics in the market today are Lead-Free, but since the properties of lead-free solders are not as thoroughly known, they may therefore be considered less desirable for critical applications, like certain aerospace or medical projects.
The failures of Lead-Free solder in BGA packages are well documented and we discuss it in more details on our BGA Reballing / Replacment page.
Currently we stock but we prefer to use Lead Solder.
Tin-copper lead-free solder,0.5mm,250g
Tin-copper lead-free solder,1.63mm,250g
In soldering of metals, flux serves a threefold purpose: it removes oxidation from the surfaces to be soldered, it seals out air thus preventing further oxidation, and by facilitating amalgamation improves wetting characteristics of the liquid solder.
Some fluxes are corrosive, so the parts have to be cleaned with a damp sponge or other absorbent material after soldering to prevent damage. Several types of flux are used in electronics.
Flux paste is very useful for general touch-up and rework of PCBs, and for the attachment of spheres to BGA and mBGA packages.
Operations such as soldering SMD (Surface mount devices) components to various PCB substrates also use Flux pastes.
Flux Pastes are available in water soluble, no-clean formulations and can be dot dispensed, screen printed or stencil printed.
We stock the following Flux Pastes
The RMA-223-TF is an RMA flux that can be used for rework, sphere attachment to BGA, CGA and CSP packages. It can be Dot dispensed, Screen printed and Stencil printed.
The NWS-4200-LFTF is a water washable tacky flux formulated and designed to meet the reflow temperatures for lead-free alloys. This Pb-free tacky flux can maintain excellent cleanability even at elevated reflow temperatures. It can be used for rework, sphere attachment to BGA packages and assembly operations such as Flip Chip attachment.
The image above shows how tacky flux paste has been thinly applied to a BGA package layout. This is in preparation for a BGA IC to be re-soldered onto the board, to help the soldering process.
Our pastes do not leave a nasty dark yellow / brown residue, which have been used by competitors. These fluxes are substandard and affect the long term reliability of the solder.
CLEAR LIQUID FLUX
We have developed an No clean water based liquid flux, mainly used for BGA reflow, Full Motherboard reflow.
It was specially developed with the following properties in mind.
- No Residue – Clear, non-conductive and non tacky and no clean
- Reflow – reflowable with peak temperature up to 270C in air
- Oxidation barrier – Protects molten solder from oxidizing for as long as possible.
- Heat Transfer – Must help transfer heat evenly and efficiently.
We are constantly improving the flux formula to make sure we get the best results possible.
Desoldering braid, also known as desoldering wick or solder wick, is finely braided 18 to 42 AWG copper wire coated with rosin flux, usually supplied on a roll.
The end of a length of braid is placed over the soldered connections of a component being removed. The connections are heated with a soldering iron until the solder melts and is wicked into the braid by capillary action. The braid is removed while the solder is still molten, its used section cut off and discarded when cool.