Colin,
You have to watch these charts as this ones shows the melting point of solder.
It's different than the working or bonding temperature which is higher.
Remember when they spoke of the solder used in automobiles or it used to be
called leading them. Anyhow, it spoke about it being applied at a higher temp
and being worked with plastically at a lower temp before it hardened.
Electrical solder does the same thing. At say 370 the solder melted for 60/40
but the working/bonding temp is 430 Deg F. I dont know why they dont show that.
If the working temp. isn't reached, you get a cold solder joint or the solder
will roll off the part even though it's at melting temp.. However, you can
apply too much heat too. They did screw up the chart as the last cloumn
supposed to be Deg. F. and not C.
Anyhow, always remember there's a melting temp and a working temp with any
filler metal. It does have a good explaination about alloying though which is
merely melting two or more elements and mixing them together. It also had a
good explanation of the term eutectic. That term always stuck with me as theres
a solder/braze manufacturer named Eutectic Castolin. They make some good stuff
and is available at your friendly neighborhood welding supply.
Best,
Will
----- Original Message -----
From: "k7fm" <k7fm@teleport.com>
To: "carl seyersdahl" <carlseye@tampabay.rr.com>, Amps@contesting.com
Subject: Re: [Amps] solder vs. High temp.
Date: Sat, 23 Jul 2005 15:54:37 -0700
>
> There are a number of sites that list the melting point of various solders.
> A quick search yielded
>
> http://et.nmsu.edu/~etti/fall97/electronics/solder.html
>
> I am still amazed that an alloy can melt at a lower temperature than the
> components.
>
> Colin K7FM
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
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