LISTSERV - TECHNET Archives - LISTSERV.IPC.ORG

TECHNET Archives

June 2000

TechNet@IPC.ORG

	LISTSERV Archives
	TECHNET Home
	TECHNET June 2000

	Log In
	Register

	Subscribe or Unsubscribe

	Search Archives

Options:	Use Monospaced Font Show Text Part by Default Show All Mail Headers
Message:	[<< First] [< Prev] [Next >] [Last >>]
Topic:	[<< First] [< Prev] [Next >] [Last >>]
Author:	[<< First] [< Prev] [Next >] [Last >>]

Subject:	Re: Resistor termination disappearing
From:	"Stephen R. Gregory" <[log in to unmask]>
Reply To:	TechNet E-Mail Forum.
Date:	Wed, 14 Jun 2000 22:17:05 EDT
Content-Type:	text/plain
Parts/Attachments:	text/plain (50 lines)

In a message dated 06/14/2000 8:47:02 PM Central Daylight Time,
[log in to unmask] writes:

> Vernon - The only place where I have seen sulfur contamination on components
>  was from packing material; cardboard boxes to be specific. We were trying
to
>  pretin Leadless Ceramic Chip Carriers that had gold castellations, and we
>  couldn't get the solder to wet to the gold. As you probably know, if you
>  can't get solder to wet to Gold, you have a problem. As for the Silver
>  depletion, are you are using Palladium-Silver terminations on the
resistors,
>  and are you using Sn62 solder?
>
>  Ed Valentine
>  Electronics Manufacturing Solutions
>  8612 Mourning Dove Road, Raleigh, NC 27615
>  Phone: (919) 270-5145, Fax: (919) 847-9971
>  Email: [log in to unmask]
>  Website: http://www.ems-consulting.com

Hi Vernon!

I'll admit that I don't know much about sulfer contamination, but I did have
a issue with palladium/ silver terminated components, and I agree with Ed.

It was with a thermistor, and if any touch-up was attempted, the termination
dissapeared...the solder joint had to be done right during initial
reflow...it could not withstand a rework cycle.

The joints did appear quite different compared to standard tin/lead
terminations as the fillets would not wet up quite as high...and if one would
try to make them look the same as standard joints, the terminations would
leech off and disappear...

-Steve Gregory-

##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in
the body:
To subscribe:   SUBSCRIBE TECHNET <your full name>
To unsubscribe:   SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information.
If you need assistance - contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
##############################################################

ATOM RSS1 RSS2

LISTSERV.IPC.ORG