This is actual the actual soldiering using a copper heat tube to a nickel plated surface.   The solder joint appears very uniform and NOT hand soldering.   Therefore I suspect some sort of automatic soldering process.
Victor,

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Gerald Bogert
Sent: Thursday, August 29, 2013 2:41 PM
To: [log in to unmask]
Subject: Re: [TN] Solder joint failure

August 29, 2013

Appears that you are talking about soldering metals to metals and not soldering to electrical components.  If this is true, mechanical soldering requirements and not J-STD-001 soldering would normally apply.

Is this a soldering or otherwise a brazing operation since many heat sinks are brazed to the copper pipes using dip braze or furnace brazed process rather than soldered.

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Whittaker, Dewey
(EHCOE)
Sent: Thursday, August 29, 2013 3:10 PM
To: [log in to unmask]
Subject: Re: [TN] Solder joint failure

Usually a sacrificial gold is the final finish over the nickel. The fluxes used to solder to nickel are unique. IMHO, no-cleans; not allowed.

Dewey

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Glidden, Kevin
Sent: Thursday, August 29, 2013 12:01 PM
To: [log in to unmask]
Subject: Re: [TN] Solder joint failure

In my experience nickel is NOT easy to solder to at all.


-----Original Message-----
From: Victor Hernandez [mailto:[log in to unmask]]
Sent: Thursday, August 29, 2013 2:53 PM
To: [log in to unmask]
Subject: [TN] Solder joint failure

Fellow TechNetters:

   Should I be concern with an electroless matted nickel plating over an
aluminum sheet metal surface and solder onto a copper heat tube?   I
recall something about directly soldering onto a nickel surface.  Beside
nickel oxidation.    Any suggestions would be greatly appreciated.

Victor,

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