is this a eutectic solder?

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I wouldn't use it to solder a rain-gutter or a tin roof, but for electronics work it should be fine.

It contains lead, so it isn't ROHS compliant, which may or may not matter to you depending on how "green" you are.

Why the concern over "eutectic"? Eutectic is a term for a substance that is a mixture of two or more other substances that has a lower melting point than any of the individual substances that make up the mixture (a relatively unusual condition). As far as I know, all solder intended for electronics is eutectic.

I_F
 
The typical mixture for non-ROHS 'eutectic' solder is 63/37 as opposed to the normal 60/40.
'Eutectic' means that is moves between liquid and solid states almost instantly while other solders go through a 'pasty' transition in a range of temperatures (about 9degreesC)
 
It's designed for electronic soldering and is eutectic, which gives more reliable joints. I use a similar 2% silver solder and am pleased with the results, otherwise I use a 63/37 eutectic solder for all electronic soldering. Both types flow well and have a nice shiny appearance after hardening.

Should be good stuff.

I've tried one of the lead free solders and wasn't particularly pleased with the appearance of the joint. It may not be a eutetic alloy.
 
Hi,
The only point where lead and tin alloys are eutectic is at 63% tin and 37% lead
no.
that applies to an alloy of only tin and lead.
If you add other constituents, the eutectic changes, but most are not eutectic.

Here are a few eutectics ( although this list is gleaned from the web and may not be accurate).

Sn5, Pb92.5, Ag2.5 536F
Sn96.5, Ag3.5 430F
Sn63, Pb37 361F
Sn20, Au80 536F
Pb97.5, Ag2.5 579F
Sn96.5, Ag3.8, Cu0.7 423F
Sn62, Pb36, Ag2 354F

This last one may be the Multicore Sn62 but where in the spec sheet does it confirm the composition or that it is eutectic?

The advantage of eutectic is the almost instant change from liquid to solid without the paste temperature range of the non eutectics. The paste range increases the chance of getting a bad joint in electrical circuitry.
 
that applies to an alloy of only tin and lead

That's what I said.


This last one may be the Multicore Sn62 but where in the spec sheet does it confirm the composition or that it is eutectic?


http://tds.loctite.com/tds5/docs/M-POFA-EN.PDF


This data sheet confirms that SN62 is 2% silver. The given melting point is a single figure rather than a range, which would indicate a eutectic alloy.

John
 
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